U.S. patent application number 13/660428 was filed with the patent office on 2013-02-28 for organometallic compounds.
The applicant listed for this patent is Scott Houston Meiere. Invention is credited to Scott Houston Meiere.
Application Number | 20130052349 13/660428 |
Document ID | / |
Family ID | 38739925 |
Filed Date | 2013-02-28 |
United States Patent
Application |
20130052349 |
Kind Code |
A1 |
Meiere; Scott Houston |
February 28, 2013 |
ORGANOMETALLIC COMPOUNDS
Abstract
This invention relates to organometallic compounds represented
by the formula
H.sub.aM(NR.sub.1R.sub.2).sub.x(NR.sub.3H).sub.y(NH.sub.2).sub.z
wherein M is a metal or metalloid, each of R.sub.1, R.sub.2 and
R.sub.3 is the same or different and is independently a hydrocarbon
group or a heteroatom-containing group, a is a value from 0 to 3, x
is a value from 0 to 3, y is a value from 0 to 4, z is a value from
0 to 4, and a+x+y+z is equal to the oxidation state of M, provided
that at least one of y and z is a value of at least 1, a process
for producing the organometallic compounds, and a method for
producing a film or coating from organometallic precursor
compounds.
Inventors: |
Meiere; Scott Houston;
(Charlotte, NY) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Meiere; Scott Houston |
Charlotte |
NY |
US |
|
|
Family ID: |
38739925 |
Appl. No.: |
13/660428 |
Filed: |
October 25, 2012 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
11807545 |
May 29, 2007 |
8318966 |
|
|
13660428 |
|
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|
60815834 |
Jun 23, 2006 |
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Current U.S.
Class: |
427/255.18 ;
423/335; 427/248.1; 556/410 |
Current CPC
Class: |
H01L 21/02219 20130101;
H01L 21/02118 20130101; H01L 21/02274 20130101; H01L 21/3185
20130101; H01L 21/02148 20130101; H01L 21/02205 20130101; C23C
16/45553 20130101; H01L 21/318 20130101; C07F 7/025 20130101; H01L
21/3141 20130101; H01L 21/0228 20130101; C23C 16/402 20130101; H01L
21/0215 20130101; H01L 21/02271 20130101; H01L 21/02216
20130101 |
Class at
Publication: |
427/255.18 ;
556/410; 423/335; 427/248.1 |
International
Class: |
C07F 7/02 20060101
C07F007/02; C23C 16/18 20060101 C23C016/18; C01B 33/12 20060101
C01B033/12 |
Claims
1. A process for the production of an organometallic compound
comprising (i) reacting in a first pot a nitrogen-containing
compound with an alkali metal, or an alkali metal-containing
compound, or an alkaline earth metal, or an alkaline earth
metal-containing compound, in the presence of a solvent and under
reaction conditions sufficient to produce a first reaction mixture
comprising a base material, (ii) adding said base material to a
second pot containing a metal source compound and optionally an
amine compound, (iii) reacting in said second pot said base
material with said metal source compound and optionally said amine
compound under reaction conditions sufficient to produce a second
reaction mixture comprising said organometallic compound, and (iv)
separating said organometallic compound from said second reaction
mixture; wherein said organometallic compound is represented by the
formula
H.sub.aM(NR.sub.1R.sub.2).sub.x(NR.sub.3H).sub.y(NH.sub.2).sub.z in
which M is a metal or metalloid, R.sub.1 is the same or different
and is a hydrocarbon group or a heteroatom-containing group,
R.sub.2 is the same or different and is a hydrocarbon group or a
heteroatom-containing group, R.sub.3 is the same or different and
is a hydrocarbon group or a heteroatom-containing group, a is a
value from 0 to 3, x is a value from 0 to 3, y is a value from 0 to
4, z is a value from 0 to 4, and a+x+y+z is equal to the oxidation
state of M, provided that at least one of y and z is a value of at
least 1.
2. The process of claim 1 wherein the metal source compound
comprises tetrachlorosilane, tetrabromosilane, hafnium
tetrachloride, tris(dimethylamino)chlorosilane,
bis(diethylamino)dichlorosilane, or bis(diethylamino)silane; the
base material comprises lithium amide, lithium ethylamide, sodium
ethylamide, or lithium t-butylamide; and the amine compound
comprises ammonia, ethylamine, or t-butylamine.
3. The process of claim 1 wherein said organometallic compound is
represented by the formula
H.sub.aSi(NR.sub.1R.sub.2).sub.x(NR.sub.3H).sub.y(NH.sub.2).sub.z
wherein R.sub.1 is the same or different and is a hydrocarbon group
or a heteroatom-containing group, R.sub.2 is the same or different
and is a hydrocarbon group or a heteroatom-containing group,
R.sub.3 is the same or different and is a hydrocarbon group or a
heteroatom-containing group, a is a value from 0 to 3, x is a value
from 0 to 3, y is a value from 0 to 4, z is a value from 0 to 4,
and a+x+y+z=4, provided that at least one of y and z is a value of
at least 1.
4. A process for the production of an organometallic compound
comprising (i) reacting in a first pot a nitrogen-containing
compound with an alkali metal, or an alkali metal-containing
compound, or an alkaline earth metal, or an alkaline earth
metal-containing compound, in the presence of a solvent and under
reaction conditions sufficient to produce a first reaction mixture
comprising a base material, (ii) adding said base material to a
second pot containing a metal source compound and optionally an
amine compound, (iii) reacting in said second pot said base
material with said metal source compound and optionally said amine
compound under reaction conditions sufficient to produce a second
reaction mixture comprising an organometallic compound derivative,
(iv) subjecting said second reaction mixture to reduction or
dehalogenation under conditions sufficient produce a third reaction
mixture comprising said organometallic compound, and (v) separating
said organometallic compound from said third reaction mixture;
wherein said organometallic compound is represented by the formula
:M(NR'.sub.1R'.sub.2).sub.q wherein M is a metal or metalloid,
R'.sub.1 is the same or different and is a hydrocarbon group or a
heteroatom-containing group, R'.sub.2 is the same or different and
is a hydrocarbon group or a heteroatom-containing group; when q is
a value of 2 or greater, R'.sub.1 or R'.sub.2 of one
(NR'.sub.1R'.sub.2) group can be combined with R'.sub.1 or R'.sub.2
of another (NR'.sub.1R'.sub.2) group to form a substituted or
unsubstituted, saturated or unsaturated cyclic group; q is a value
equal to or less than the oxidation state of M, and : represents 2
electrons.
5. The process of claim 4 wherein the metal source compound
comprises tetrachlorosilane, tetrabromosilane, hafnium
tetrachloride, bis(dimethylamino)dichlorosilane,
bis(diethylamino)dichlorosilane, bis(diethylamino)silane,
(N,N'-di-tert-butylethene-1,2-diamino)dichlorosilane,
(N,N'-di-tert-butylethylene-1,2-diamino)dichlorosilane,
(N,N'-diisopropylethene-1,2-diamino)dichlorosilane,
bis(di-tert-butylamino)dichlorosilane, or
bis(di-tert-amylamino)dichlorosilane; the base material comprises
lithium di-tert-butylamide, lithium di-tert-amylamide, lithium
N,N'-di-tert-butylethylene-1,2-diamide, lithium
N,N'-diisopropylethene-1,2-diamide, or lithium
N,N'-di-tert-butylethene-1,2-diamide; and the amine compound
comprises di-tert-butylamine, di-tert-amylamine,
N,N'-di-tert-butylethylene-1,2-diamine,
N,N'-diisopropylethene-1,2-diamine, or
N,N'-di-tert-butylethene-1,2-diamine.
6. The process of claim 4 wherein said organometallic compound is
represented by the formula :Si(NR'.sub.1R'.sub.2).sub.2 wherein
R'.sub.1 is the same or different and is a hydrocarbon group or a
heteroatom-containing group, R'.sub.2 is the same or different and
is a hydrocarbon group or a heteroatom-containing group; R'.sub.1
or R'.sub.2 of one (NR'.sub.1R'.sub.2) group can be combined with
R'.sub.1 or R'.sub.2 of another (NR'.sub.1R'.sub.2) group to form a
substituted or unsubstituted, saturated or unsaturated cyclic
group; and : represents 2 electrons.
7. A method for producing a film, coating or powder by decomposing
an organometallic precursor compound represented by the formula
H.sub.aM(NR.sub.1R.sub.2).sub.x(NR.sub.3H).sub.y(NH.sub.2).sub.z
wherein M is a metal or metalloid, R.sub.1 is the same or different
and is a hydrocarbon group or a heteroatom-containing group,
R.sub.2 is the same or different and is a hydrocarbon group or a
heteroatom-containing group, R.sub.3 is the same or different and
is a hydrocarbon group or a heteroatom-containing group, a is a
value from 0 to 3, x is a value from 0 to 3, y is a value from 0 to
4, z is a value from 0 to 4, and a+x+y+z is equal to the oxidation
state of M, provided that at least one of y and z is a value of at
least 1, thereby producing the film, coating or powder.
8. The method of claim 7 wherein the decomposing of said
organometallic precursor compound is thermal, chemical,
photochemical or plasma-activated.
9. The method of claim 7 wherein said organometallic precursor
compound is vaporized and the vapor is directed into a deposition
reactor housing a substrate.
10. The method of claim 9 wherein said substrate is comprised of a
material selected from the group consisting of a metal, a metal
silicide, a semiconductor, an insulator and a barrier material.
11. The method of claim 9 wherein said substrate is a patterned
wafer.
12. The method of claim 7 wherein said film, coating or powder is
produced by a chemical vapor deposition or atomic layer
deposition.
13. The method of claim 7 wherein said organometallic precursor
compound is represented by the formula
H.sub.aSi(NR.sub.1R.sub.2).sub.x(NR.sub.3H).sub.y(NH.sub.2).sub.z
wherein R.sub.1 is the same or different and is a hydrocarbon group
or a heteroatom-containing group, R.sub.2 is the same or different
and is a hydrocarbon group or a heteroatom-containing group,
R.sub.3 is the same or different and is a hydrocarbon group or a
heteroatom-containing group, a is a value from 0 to 3, x is a value
from 0 to 3, y is a value from 0 to 4, z is a value from 0 to 4,
and a+x+y+z=4, provided that at least one of y and z is a value of
at least 1, thereby producing the film, coating or powder.
14. A method for producing a film, coating or powder by decomposing
an organometallic precursor compound represented by the formula
:M(NR'.sub.1R'.sub.2).sub.q wherein M is a metal or metalloid,
R'.sub.1 is the same or different and is a hydrocarbon group or a
heteroatom-containing group, R'.sub.2 is the same or different and
is a hydrocarbon group or a heteroatom-containing group; when a is
a value of 2 or greater, R'.sub.1 or R'.sub.2 of one
(NR'.sub.1R'.sub.2) group can be combined with R'.sub.1 or R'.sub.2
of another (NR'.sub.1R'.sub.2) group to form a substituted or
unsubstituted, saturated or unsaturated cyclic group; a is a value
equal to or less than the oxidation state of M, and : represents 2
electrons, thereby producing the film, coating or powder.
15. The method of claim 14 wherein the decomposing of said
organometallic precursor compound is thermal, chemical,
photochemical or plasma-activated.
16. The method of claim 14 wherein said organometallic precursor
compound is vaporized and the vapor is directed into a deposition
reactor housing a substrate.
17. The method of claim 16 wherein said substrate is comprised of a
material selected from the group consisting of a metal, a metal
silicide, a semiconductor, an insulator and a barrier material.
18. The method of claim 16 wherein said substrate is a patterned
wafer.
19. The method of claim 14 wherein said film, coating or powder is
produced by a chemical vapor deposition or atomic layer
deposition.
20. The method of claim 14 wherein said organometallic precursor
compound is represented by the formula :Si(NR'.sub.1R'.sub.2).sub.2
wherein R'.sub.1 is the same or different and is a hydrocarbon
group or a heteroatom-containing group, R'.sub.2 is the same or
different and is a hydrocarbon group or a heteroatom-containing
group; R'.sub.1 or R'.sub.2 of one (NR'.sub.1R'.sub.2) group can be
combined with R'.sub.1 or R'.sub.2 of another (NR'.sub.1R'.sub.2)
group to form a substituted or unsubstituted, saturated or
unsaturated cyclic group; and : represents 2 electrons, thereby
producing the film, coating or powder.
Description
RELATED APPLICATION
[0001] This application is a division of U.S. patent application
Ser. No. 11/807,545, filed May 29, 2007, which claims priority to
U.S. Provisional Application Ser. No. 60/815,834, filed on Jun. 23,
2006, and is incorporated by reference herein in its entirety.
FIELD OF THE INVENTION
[0002] This invention relates to organometallic compounds
represented by the formula
H.sub.aM(NR.sub.1R.sub.2).sub.x(NR.sub.3H).sub.y(NH.sub.2).sub.z
wherein M is a metal or metalloid, each of R.sub.1, R.sub.2 and
R.sub.3 is the same or different and is independently a hydrocarbon
group or a heteroatom-containing group, a is a value from 0 to 3, x
is a value from 0 to 3, y is a value from 0 to 4, z is a value from
0 to 4, and a+x+y+z is equal to the oxidation state of M, provided
that at least one of y and z is a value of at least 1, a process
for producing the organometallic compounds, and a method for
producing a film or coating from organometallic precursor
compounds.
BACKGROUND OF THE INVENTION
[0003] Chemical vapor deposition methods are employed to form films
of material on substrates such as wafers or other surfaces during
the manufacture or processing of semiconductors. In chemical vapor
deposition, a chemical vapor deposition precursor, also known as a
chemical vapor deposition chemical compound, is decomposed
thermally, chemically, photochemically or by plasma activation, to
form a thin film having a desired composition. For instance, a
vapor phase chemical vapor deposition precursor can be contacted
with a substrate that is heated to a temperature higher than the
decomposition temperature of the precursor, to form a metal or
metal oxide film on the substrate. Preferably, chemical vapor
deposition precursors are volatile, heat decomposable and capable
of producing uniform films under chemical vapor deposition
conditions.
[0004] The semiconductor industry is currently considering the use
of thin films of various metals for a variety of applications. Many
organometallic complexes have been evaluated as potential
precursors for the formation of these thin films. A need exists in
the industry for developing new compounds and for exploring their
potential as chemical vapor deposition precursors for film
depositions.
[0005] For the chemical vapor deposition of silicon-containing
films (e.g., SiO.sub.2), compounds such as silane, chlorinated
silanes, and alkoxy silanes (e.g., TEOS) are well known. However,
as next generation oxide materials with higher dielectric
constants, so called `high-k` materials (e.g., HfO.sub.2), are
integrated, and concurrently new precursors are developed for these
materials (e.g., hafnium amides), other silicon precursors will
require development for the deposition of ternary systems and
beyond (e.g., hafnium silicates).
[0006] For silicon amide compounds with cyclic amide ligands, an
example reported in the literature is tetrakis(pyrrolidinyl)silane
(a solid at room temperature, mp=30.degree. C.). Inorg. Nucl. Chem.
Letters 1969 5 733 discloses tetrakis(pyrrolidinyl)silane compound
and a low yield synthetic method for preparation thereof.
[0007] U.S. Patent Application Publication Nos. US 2002/0187644 A1
and US 2002/0175393 A1 disclose metalloamide precursor compositions
having stated utility for forming dielectric thin films such as
gate dielectric, high dielectric constant metal oxides, and
ferroelectric metal oxides and to a low temperature chemical vapor
deposition process for deposition of such dielectric thin films
utilizing the compositions.
[0008] A need exists in the industry for an improved silicon
dioxide atomic layer deposition precursors. Although many silicon
precursors are readily available (e.g., silane, tetrachlorosilane,
tetraethoxysilane, tetrakis(dimethylamino)silane), none of these
silicon precursors have the desired optimal properties of an atomic
layer deposition precursor for certain applications. One of these
applications is for a nanolaminate structures in tandem with other
materials, for example a high-k material such as HfO.sub.2. For
this application, a balance of reactivity and thermal stability
must be achieved to grow self-limiting SiO.sub.2 with an adequate
growth rate. Compounds such as silane may be too unstable,
tetrachlorosilane may yield halogen impurities, and
tetraethoxysilane and tetrakis(dimethylamino)silane may be too
unreactive within the temperature parameters of the application.
The problem is therefore to generate a suitable atomic layer
deposition precursor for such an application.
[0009] Further, in developing methods for forming thin films by
chemical vapor deposition or atomic layer deposition methods, a
need continues to exist for precursors that preferably are liquid
at room temperature, have adequate vapor pressure, have appropriate
thermal stability (i.e., for chemical vapor deposition will
decompose on the heated substrate but not during delivery, and for
atomic layer deposition will not decompose thermally but will react
when exposed to co-reactant), can form uniform films, and will
leave behind very little, if any, undesired impurities (e.g.,
halides, carbon, etc.). Therefore, a need continues to exist for
developing new compounds and for exploring their potential as
chemical vapor or atomic layer deposition precursors for film
depositions. It would therefore be desirable in the art to provide
a precursor that possesses some, or preferably all, of the above
characteristics.
SUMMARY OF THE INVENTION
[0010] This invention relates in part to organometallic compounds
represented by the formula
H.sub.aM(NR.sub.1R.sub.2).sub.x(NR.sub.3H).sub.y(NH.sub.2).sub.z
wherein M is a metal or metalloid, R.sub.1 is the same or different
and is a hydrocarbon group or a heteroatom-containing group,
R.sub.2 is the same or different and is a hydrocarbon group or a
heteroatom-containing group, R.sub.3 is the same or different and
is a hydrocarbon group or a heteroatom-containing group, a is a
value from 0 to 3, x is a value from 0 to 3, y is a value from 0 to
4, z is a value from 0 to 4, and a+x+y+z is equal to the oxidation
state of M, provided that at least one of y and z is a value of at
least 1.
[0011] More particularly, this invention relates in part to
organometallic compounds represented by the formula
H.sub.aSi(NR.sub.1R.sub.2).sub.x(NR.sub.3H).sub.y(NH.sub.2).sub.z
wherein R.sub.1 is the same or different and is a hydrocarbon group
or a heteroatom-containing group, R.sub.2 is the same or different
and is a hydrocarbon group or a heteroatom-containing group,
R.sub.3 is the same or different and is a hydrocarbon group or a
heteroatom-containing group, a is a value from 0 to 3, x is a value
from 0 to 3, y is a value from 0 to 4, z is a value from 0 to 4,
and a+x+y+z=4, provided that at least one of y and z is a value of
at least 1.
[0012] This invention also relates in part to organometallic
compounds represented by the formula :M(NR'.sub.1R'.sub.2).sub.q
wherein M is a metal or metalloid, R'.sub.1 is the same or
different and is a hydrocarbon group or a heteroatom-containing
group, R'.sub.2 is the same or different and is a hydrocarbon group
or a heteroatom-containing group; when q is a value of 2 or
greater, R'.sub.1 or R'.sub.2 of one (NR'.sub.1R'.sub.2) group can
be combined with R'.sub.1 or R'.sub.2 of another
(NR'.sub.1R'.sub.2) group to form a substituted or unsubstituted,
saturated or unsaturated cyclic group; q is a value equal to or
less than the oxidation state of M, and : represents 2
electrons.
[0013] More particularly, this invention also relates in part to
organometallic compounds represented by the formula
:Si(NR'.sub.1R'.sub.2).sub.2 wherein R'.sub.1 is the same or
different and is a hydrocarbon group or a heteroatom-containing
group, R'.sub.2 is the same or different and is a hydrocarbon group
or a heteroatom-containing group; R'.sub.1 or R'.sub.2 of one
(NR'.sub.1R'.sub.2) group can be combined with R'.sub.1 or R'.sub.2
of another (NR'.sub.1R'.sub.2) group to form a substituted or
unsubstituted, saturated or unsaturated cyclic group; and :
represents 2 electrons.
[0014] This invention further relates in part to a process for the
production of an organometallic compound comprising (i) reacting in
a first pot a nitrogen-containing compound with an alkali metal, or
an alkali metal-containing compound, or an alkaline earth metal, or
an alkaline earth metal-containing compound, in the presence of a
solvent and under reaction conditions sufficient to produce a first
reaction mixture comprising a base material, (ii) adding said base
material to a second pot containing a metal source compound and
optionally an amine compound, (iii) reacting in said second pot
said base material with said metal source compound and optionally
said amine compound under reaction conditions sufficient to produce
a second reaction mixture comprising said organometallic compound,
and (iv) separating said organometallic compound from said second
reaction mixture; wherein said organometallic compound is
represented by the formula
H.sub.aM(NR.sub.1R.sub.2).sub.x(NR.sub.3H).sub.y(NH.sub.2).sub.z in
which M is a metal or metalloid, R.sub.1 is the same or different
and is a hydrocarbon group or a heteroatom-containing group,
R.sub.2 is the same or different and is a hydrocarbon group or a
heteroatom-containing group, R.sub.3 is the same or different and
is a hydrocarbon group or a heteroatom-containing group, a is a
value from 0 to 3, x is a value from 0 to 3, y is a value from 0 to
4, z is a value from 0 to 4, and a+x+y+z is equal to the oxidation
state of M, provided that at least one of y and z is a value of at
least 1. The organometallic compound yield resulting from the
process of this invention can be 60% or greater, preferably 75% or
greater, and more preferably 90% or greater.
[0015] More particularly, this invention further relates in part to
a process for the production of an organometallic compound
comprising (i) reacting in a first pot a nitrogen-containing
compound with an alkali metal, or an alkali metal-containing
compound, or an alkaline earth metal, or an alkaline earth
metal-containing compound, in the presence of a solvent and under
reaction conditions sufficient to produce a first reaction mixture
comprising a base material, (ii) adding said base material to a
second pot containing a metal source compound and optionally an
amine compound, (iii) reacting in said second pot said base
material with said metal source compound and optionally said amine
compound under reaction conditions sufficient to produce a second
reaction mixture comprising said organometallic compound, and (iv)
separating said organometallic compound from said second reaction
mixture; wherein said organometallic compound is represented by the
formula
H.sub.aSi(NR.sub.1R.sub.2).sub.x(NR.sub.3H).sub.y(NH.sub.2).sub.z
wherein R.sub.1 is the same or different and is a hydrocarbon group
or a heteroatom-containing group, R.sub.2 is the same or different
and is a hydrocarbon group or a heteroatom-containing group,
R.sub.3 is the same or different and is a hydrocarbon group or a
heteroatom-containing group, a is a value from 0 to 3, x is a value
from 0 to 3, y is a value from 0 to 4, z is a value from 0 to 4,
and a+x+y+z=4, provided that at least one of y and z is a value of
at least 1. The organometallic compound yield resulting from the
process of this invention can be 60% or greater, preferably 75% or
greater, and more preferably 90% or greater.
[0016] This invention yet further relates in part to a process for
the production of an organometallic compound comprising (i)
reacting in a first pot a nitrogen-containing compound with an
alkali metal, or an alkali metal-containing compound, or an
alkaline earth metal, or an alkaline earth metal-containing
compound, in the presence of a solvent and under reaction
conditions sufficient to produce a first reaction mixture
comprising a base material, (ii) adding said base material to a
second pot containing a metal source compound and optionally an
amine compound, (iii) reacting in said second pot said base
material with said metal source compound and optionally said amine
compound under reaction conditions sufficient to produce a second
reaction mixture comprising an organometallic compound derivative,
(iv) subjecting said second reaction mixture to reduction or
dehalogenation under conditions sufficient produce a third reaction
mixture comprising said organometallic compound, and (v) separating
said organometallic compound from said third reaction mixture;
wherein said organometallic compound is represented by the formula
:M(NR'.sub.1R'.sub.2).sub.q wherein M is a metal or metalloid,
R'.sub.1 is the same or different and is a hydrocarbon group or a
heteroatom-containing group, R'.sub.2 is the same or different and
is a hydrocarbon group or a heteroatom-containing group; when a is
a value of 2 or greater, R'.sub.1 or R'.sub.2 of one
(NR'.sub.1R'.sub.2) group can be combined with R'.sub.1 or R'.sub.2
of another (NR'.sub.1R'.sub.2) group to form a substituted or
unsubstituted, saturated or unsaturated cyclic group; q is a value
equal to or less than the oxidation state of M, and : represents 2
electrons. The organometallic compound yield resulting from the
process of this invention can be 60% or greater, preferably 75% or
greater, and more preferably 90% or greater.
[0017] More particularly, this invention yet further relates in
part to a process for the production of an organometallic compound
comprising (i) reacting in a first pot a nitrogen-containing
compound with an alkali metal, or an alkali metal-containing
compound, or an alkaline earth metal, or an alkaline earth
metal-containing compound, in the presence of a solvent and under
reaction conditions sufficient to produce a first reaction mixture
comprising a base material, (ii) adding said base material to a
second pot containing a metal source compound and optionally an
amine compound, (iii) reacting in said second pot said base
material with said metal source compound and optionally said amine
compound under reaction conditions sufficient to produce a second
reaction mixture comprising an organometallic compound derivative,
(iv) subjecting said second reaction mixture to reduction or
dehalogenation under conditions sufficient produce a third reaction
mixture comprising said organometallic compound, and (v) separating
said organometallic compound from said third reaction mixture;
wherein said organometallic compound is represented by the formula
:Si(NR'.sub.1R'.sub.2).sub.2 wherein R'.sub.1 is the same or
different and is a hydrocarbon group or a heteroatom-containing
group, R'.sub.2 is the same or different and is a hydrocarbon group
or a heteroatom-containing group; R'.sub.1 or R'.sub.2 of one
(NR'.sub.1R'.sub.2) group can be combined with R'.sub.1 or R'.sub.2
of another (NR'.sub.1R'.sub.2) group to form a substituted or
unsubstituted, saturated or unsaturated cyclic group; and :
represents 2 electrons. The organometallic compound yield resulting
from the process of this invention can be 60% or greater,
preferably 75% or greater, and more preferably 90% or greater.
[0018] This invention also relates in part to a method for
producing a film, coating or powder by decomposing an
organometallic precursor compound represented by the formula
H.sub.aM(NR.sub.1R.sub.2).sub.x(NR.sub.3H).sub.y(NH.sub.2).sub.z
wherein M is a metal or metalloid, R.sub.1 is the same or different
and is a hydrocarbon group or a heteroatom-containing group,
R.sub.2 is the same or different and is a hydrocarbon group or a
heteroatom-containing group, R.sub.3 is the same or different and
is a hydrocarbon group or a heteroatom-containing group, a is a
value from 0 to 3, x is a value from 0 to 3, y is a value from 0 to
4, z is a value from 0 to 4, and a+x+y+z is equal to the oxidation
state of M, provided that at least one of y and z is a value of at
least 1, thereby producing the film, coating or powder. Typically,
the decomposing of said organometallic precursor compound is
thermal, chemical, photochemical or plasma-activated.
[0019] More particularly, this invention also relates in part to a
method for producing a film, coating or powder by decomposing an
organometallic precursor compound represented by the formula
H.sub.aSi(NR.sub.1R.sub.2).sub.x(NR.sub.3H).sub.y(NH.sub.2).sub.z
wherein R.sub.1 is the same or different and is a hydrocarbon group
or a heteroatom-containing group, R.sub.2 is the same or different
and is a hydrocarbon group or a heteroatom-containing group,
R.sub.3 is the same or different and is a hydrocarbon group or a
heteroatom-containing group, a is a value from 0 to 3, x is a value
from 0 to 3, y is a value from 0 to 4, z is a value from 0 to 4,
and a+x+y+z=4, provided that at least one of y and z is a value of
at least 1, thereby producing the film, coating or powder.
Typically, the decomposing of said organometallic precursor
compound is thermal, chemical, photochemical or
plasma-activated.
[0020] This invention further relates in part to a method for
producing a film, coating or powder by decomposing an
organometallic precursor compound represented by the formula
:M(NR'.sub.1R'.sub.2).sub.q wherein M is a metal or metalloid,
R'.sub.1 is the same or different and is a hydrocarbon group or a
heteroatom-containing group, R'.sub.2 is the same or different and
is a hydrocarbon group or a heteroatom-containing group; when q is
a value of 2 or greater, R'.sub.1 or R'.sub.2 of one
(NR'.sub.1R'.sub.2) group can be combined with R'.sub.1 or R'.sub.2
of another (NR'.sub.1R'.sub.2) group to form a substituted or
unsubstituted, saturated or unsaturated cyclic group; q is a value
equal to or less than the oxidation state of M, and : represents 2
electrons, thereby producing the film, coating or powder.
Typically, the decomposing of said organometallic precursor
compound is thermal, chemical, photochemical or
plasma-activated.
[0021] More particularly, this invention further relates in part to
a method for producing a film, coating or powder by decomposing an
organometallic precursor compound represented by the formula
:Si(NR'.sub.1R'.sub.2).sub.2 wherein R'.sub.1 is the same or
different and is a hydrocarbon group or a heteroatom-containing
group, R'.sub.2 is the same or different and is a hydrocarbon group
or a heteroatom-containing group; R'.sub.1 or R'.sub.2 of one
(NR'.sub.1R'.sub.2) group can be combined with R'.sub.1 or R'.sub.2
of another (NR'.sub.1R'.sub.2) group to form a substituted or
unsubstituted, saturated or unsaturated cyclic group; and :
represents 2 electrons, thereby producing the film, coating or
powder. Typically, the decomposing of said organometallic precursor
compound is thermal, chemical, photochemical or
plasma-activated.
[0022] This invention yet further relates in part to organometallic
precursor compound mixtures comprising (i) a first organometallic
precursor compound represented by the formula
H.sub.aM(NR.sub.1R.sub.2).sub.x(NR.sub.3H).sub.y(NH.sub.2).sub.z
wherein M is a metal or metalloid, R.sub.1 is the same or different
and is a hydrocarbon group or a heteroatom-containing group,
R.sub.2 is the same or different and is a hydrocarbon group or a
heteroatom-containing group, R.sub.3 is the same or different and
is a hydrocarbon group or a heteroatom-containing group, a is a
value from 0 to 3, x is a value from 0 to 3, y is a value from 0 to
4, z is a value from 0 to 4, and a+x+y+z is equal to the oxidation
state of M, provided that at least one of y and z is a value of at
least 1, and (ii) one or more different organometallic precursor
compounds (e.g., a hafnium-containing, tantalum-containing or
molybdenum-containing organometallic precursor compound).
[0023] More particularly, this invention yet further relates in
part to organometallic precursor compound mixtures comprising (i) a
first organometallic precursor compound represented by the formula
H.sub.aSi(NR.sub.1R.sub.2).sub.x(NR.sub.3H).sub.y(NH.sub.2).sub.z
wherein R.sub.1 is the same or different and is a hydrocarbon group
or a heteroatom-containing group, R.sub.2 is the same or different
and is a hydrocarbon group or a heteroatom-containing group,
R.sub.3 is the same or different and is a hydrocarbon group or a
heteroatom-containing group, a is a value from 0 to 3, x is a value
from 0 to 3, y is a value from 0 to 4, z is a value from 0 to 4,
and a+x+y+z=4, provided that at least one of y and z is a value of
at least 1, and (ii) one or more different organometallic precursor
compounds (e.g., a hafnium-containing, tantalum-containing or
molybdenum-containing organometallic precursor compound).
[0024] This invention also relates in part to organometallic
precursor compound mixtures comprising (i) a first organometallic
precursor compound represented by the formula
:M(NR'.sub.1R'.sub.2).sub.q wherein M is a metal or metalloid,
R'.sub.1 is the same or different and is a hydrocarbon group or a
heteroatom-containing group, R'.sub.2 is the same or different and
is a hydrocarbon group or a heteroatom-containing group; when q is
a value of 2 or greater, R'.sub.1 or R'.sub.2 of one
(NR'.sub.1R'.sub.2) group can be combined with R'.sub.1 or R'.sub.2
of another (NR'.sub.1R'.sub.2) group to form a substituted or
unsubstituted, saturated or unsaturated cyclic group; q is a value
equal to or less than the oxidation state of M, and : represents 2
electrons, and (ii) one or more different organometallic precursor
compounds (e.g., a hafnium-containing, tantalum-containing or
molybdenum-containing organometallic precursor compound).
[0025] More particularly, this invention also relates in part to
organometallic precursor compound mixtures comprising (i) a first
organometallic precursor compound represented by the formula
:Si(NR'.sub.1R'.sub.2).sub.2 wherein R'.sub.1 is the same or
different and is a hydrocarbon group or a heteroatom-containing
group, R'.sub.2 is the same or different and is a hydrocarbon group
or a heteroatom-containing group; R'.sub.1 or R'.sub.2 of one
(NR'.sub.1R'.sub.2) group can be combined with R'.sub.1 or R'.sub.2
of another (NR'.sub.1R'.sub.2) group to form a substituted or
unsubstituted, saturated or unsaturated cyclic group; and :
represents 2 electrons, and (ii) one or more different
organometallic precursor compounds (e.g., a hafnium-containing,
tantalum-containing or molybdenum-containing organometallic
precursor compound).
[0026] This invention relates in particular to `next generation`
depositions involving amide-based silicon precursors. These
precursors can have advantages over the other known precursors,
especially when utilized in tandem with other `next-generation`
materials (e.g., hafnium, tantalum and molybdenum), for the
formation of silicates, silicon oxynitrides, and the like. These
silicon-containing materials can be used for a variety of purposes
such as dielectrics, barriers, and electrodes, and in many cases
show improved properties (thermal stability, desired morphology,
less diffusion, lower leakage, less charge trapping, and the like)
than the non-silicon containing films.
[0027] The invention has several advantages. For example, the
processes of the invention are useful in generating organometallic
compounds that have varied chemical structures and physical
properties. Films generated from the organometallic compound
precursors can be deposited with a short incubation time, and the
films deposited from the organometallic compound precursors exhibit
good smoothness.
[0028] This invention relates in particular to chemical vapor
deposition and atomic layer deposition precursors for next
generation devices, specifically organometallic precursors that are
liquid at room temperature, i.e., 20.degree. C.
[0029] The organometallic precursor compounds of this invention can
provide desired properties of an atomic layer deposition precursor
for applications involving nanolaminate structures in tandem with
other materials, for example, a high-k material such as HfO.sub.2.
For this application, a balance of reactivity and thermal stability
must be achieved to grow self-limiting SiO.sub.2 with an adequate
growth rate. Compounds such as silane may be too unstable,
tetrachlorosilane may yield halogen impurities, and
tetraethoxysilane and tetrakis(dimethylamino)silane may be too
unreactive within the temperature parameters of the application.
The organometallic precursor compounds of this invention can be
suitable atomic layer deposition precursors for such an
application.
DETAILED DESCRIPTION OF THE INVENTION
[0030] This invention involves the synthesis and use of silicon
amide compounds that are comprised of at least one --NH.sub.2 or
--NR.sub.3H moiety (where R.sub.3 is a hydrocarbon group or a
heteroatom-containing group such as an alkyl (e.g., methyl,
t-butyl)). The introduction of this type of ligand can increase the
reactivity and/or decrease the thermal stability of the silicon
precursor due to the presence of the N--H bond, which can allow for
alternate reaction and/or decomposition pathways. This precursor
can yield improved performance for SiO.sub.2 deposition or other
silicon based films (e.g., silicon nitride, hafnium silicate,
etc.). The organometallic precursor compounds of this invention can
yield a desired mix of thermal stability, reactivity and volatility
for the desired application. Other structures may also be useful,
for example, a hydroxyl ligand in tandem with amide ligands.
[0031] As indicated above, this invention relates to organometallic
compounds represented by the formula
H.sub.aM(NR.sub.1R.sub.2).sub.x(NR.sub.3H).sub.y(NH.sub.2).sub.z
wherein M is a metal or metalloid, each of R.sub.1, R.sub.2 and
R.sub.3 is the same or different and is independently a hydrocarbon
group or a heteroatom-containing group, a is a value from 0 to 3,
preferably 0 or 1, x is a value from 0 to 3, preferably 2 or 3, y
is a value from 0 to 4, preferably 0 or 1, z is a value from 0 to
4, preferably 1 or 2, and a+x+y+z is equal to the oxidation state
of M, provided that at least one of y and z is a value of at least
1. For purposes of this invention, with respect to organometallic
compounds (but not precursors) of the above formula, when M is Si,
a is a value of 0, x is a value of 3, y is a value of 0, z is a
value of 1, then one of R.sub.1 and R.sub.2 is other than methyl.
Also, for purposes of this invention, with respect to
organometallic compounds and precursors of the above formula, when
M is Si, a is a value of 2, x is a value of 0, y is a value of 2, z
is a value of 0, then R.sub.3 is other than tert-butyl.
[0032] Typically, R.sub.1, R.sub.2 and R.sub.3 are the same or
different and are independently hydrogen, alkyl; a substituted or
unsubstituted, saturated or unsaturated, hydrocarbon, aromatic
hydrocarbon, cycloaliphatic hydrocarbon, aromatic heterocycle,
cycloaliphatic heterocycle, alkyl halide, silylated hydrocarbon,
ether, polyether, thioether, ester, lactone, amide, amine,
polyamine, nitrile; or mixtures thereof. R.sub.1, R.sub.2 and
R.sub.3 can also include substituted or unsubstituted, saturated or
unsaturated, cyclic amido or amino groups, for example, aziridinyl,
azetidinyl, pyrrolidinyl, thiazolidinyl, piperidinyl, pyrrolyl,
pyridinyl, pyrimidinyl, pyrrolinyl, pyrazolyl, thiazolyl, oxazolyl,
imidazolyl, imidazolidinonyl, imidazolidinethionyl, quinolinyl,
isoquinolinyl, carbazolyl, triazolyl, indolyl and purinyl.
Preferably, each of R.sub.1, R.sub.2 and R.sub.3 is the same or
different and is independently hydrogen, alkyl, or mixtures
thereof. Typically, M is selected from Si, Ti, Zr, Hf, V, Nb, Ta,
Cr, Mo, W, Al, Ga, Ge, a Lanthanide series element or an Actinide
series element.
[0033] As also indicated above, this invention relates in part to
organometallic compounds represented by the formula
:M(NR'.sub.1R'.sub.2).sub.q wherein M is a metal or metalloid,
R'.sub.1 is the same or different and is a hydrocarbon group or a
heteroatom-containing group, R'.sub.2 is the same or different and
is a hydrocarbon group or a heteroatom-containing group; when q is
a value of 2 or greater, R'.sub.1 or R'.sub.2 of one
(NR'.sub.1R'.sub.2) group can be combined with R'.sub.1 or R'.sub.2
of another (NR'.sub.1R'.sub.2) group to form a substituted or
unsubstituted, saturated or unsaturated cyclic group; q is a value
equal to or less than the oxidation state of M, and : represents 2
electrons. Typically, the oxidation state of M is a value of q or
q+2. For purposes of this invention, with respect to organometallic
compounds (but not precursors) of the above formula, when M is Si,
R.sub.1 is tert-butyl, R.sub.2 is CH, x is a value of 2, then the
R.sub.2 groups cannot be bound together by a carbon-carbon double
bond creating a cyclic system.
[0034] Typically, R'.sub.1 and R'.sub.2 are the same or different
and are independently hydrogen, alkyl; a substituted or
unsubstituted, saturated or unsaturated, hydrocarbon, aromatic
hydrocarbon, cycloaliphatic hydrocarbon, aromatic heterocycle,
cycloaliphatic heterocycle, alkyl halide, silylated hydrocarbon,
ether, polyether, thioether, ester, lactone, amide, amine,
polyamine, nitrile; or mixtures thereof. R'.sub.1 and R'.sub.2 can
also include substituted or unsubstituted, saturated or
unsaturated, cyclic amido or amino groups, for example, aziridinyl,
azetidinyl, pyrrolidinyl, thiazolidinyl, piperidinyl, pyrrolyl,
pyridinyl, pyrimidinyl, pyrrolinyl, pyrazolyl, thiazolyl, oxazolyl,
imidazolyl, imidazolidinonyl, imidazolidinethionyl, quinolinyl,
isoquinolinyl, carbazolyl, triazolyl, indolyl and purinyl.
Preferably, each of R'.sub.1 and R'.sub.2 is the same or different
and is independently hydrogen, alkyl, or mixtures thereof, or
R'.sub.1 or R'.sub.2 of one (NR'.sub.1R'.sub.2) group can be
combined with R'.sub.1 or R'.sub.2 of another (NR'.sub.1R'.sub.2)
group to form a substituted or unsubstituted, saturated or
unsaturated cyclic group.
[0035] In a preferred embodiment, this invention relates to
organometallic compounds represented by the formula
H.sub.aSi(NR.sub.1R.sub.2).sub.x(NR.sub.3H).sub.y(NH.sub.2).sub.z
wherein each of R.sub.1, R.sub.2 and R.sub.3 is the same or
different and is independently a hydrocarbon group or a
heteroatom-containing group, a is a value from 0 to 3, preferably 0
or 1, x is a value from 0 to 3, preferably 2 or 3, y is a value
from 0 to 4, preferably 0 or 1, z is a value from 0 to 4,
preferably 1 or 2, and a+x+y+z=4, provided that at least one of y
and z is a value of at least 1. For purposes of this invention,
with respect to organometallic compounds (but not precursors) of
the above formula, when a is a value of 0, x is a value of 3, y is
a value of 0, z is a value of 1, then one of R.sub.1 and R.sub.2 is
other than methyl. Also, for purposes of this invention, with
respect to organometallic compounds and precursors of the above
formula, when a is a value of 2, x is a value of 0, y is a value of
2, z is a value of 0, then R.sub.3 is other than tert-butyl.
[0036] In another preferred embodiment, this invention relates to
organometallic compounds represented by the formula
:Si(NR'.sub.1R'.sub.2).sub.2 wherein R'.sub.1 is the same or
different and is a hydrocarbon group or a heteroatom-containing
group, R'.sub.2 is the same or different and is a hydrocarbon group
or a heteroatom-containing group; R'.sub.1 or R'.sub.2 of one
(NR'.sub.1R'.sub.2) group can be combined with R'.sub.1 or R'.sub.2
of another (NR'.sub.1R'.sub.2) group to form a substituted or
unsubstituted, saturated or unsaturated cyclic group; and :
represents 2 electrons. For purposes of this invention, with
respect to organometallic compounds (but not precursors) of the
above formula, when R.sub.1 is tert-butyl, R.sub.2 is CH, x is a
value of 2, then the R.sub.2 groups cannot be bound together by a
carbon-carbon double bond creating a cyclic system.
[0037] Illustrative organometallic compounds of this invention
include, for example, tris(dimethylamino)silylamine,
tris(pyrrolyl)silylamine, tris(2-methylpyrrolidinyl)silylamine,
tris(imidazolyl)silylamine, tris(1-methylpiperazinyl)silylamine,
tris(pyrazolyl)silylamine, tetrakis(ethylamino)silane,
tris(dimethylamino)(ethylamino)silane,
N,N'-di-tert-butylethene-1,2-diaminosilylene,
N,N'-di-tert-butylethylene-1,2-diaminosilylene,
N,N'-diisopropylethene-1,2-diaminosilylene,
bis(di-tert-butylamino)silylene, bis(di-tert-amylamino)silylene,
and the like.
[0038] Illustrative organometallic compounds of this invention can
be represented by the formulae:
##STR00001##
[0039] The organometallic precursor compounds of this invention may
be homoleptic, i.e., all R radicals are the same such as
tetrakis(ethylamino)silane or heteroleptic, i.e., one or more of
the R radicals are different from each other such as
tris(ethylmethylamino)(tert-butylamino)silane.
[0040] As indicated above, this invention also relates to a process
for the production of an organometallic compound comprising (i)
reacting in a first pot a nitrogen-containing compound with an
alkali metal, or an alkali metal-containing compound, or an
alkaline earth metal, or an alkaline earth metal-containing
compound, in the presence of a solvent and under reaction
conditions sufficient to produce a first reaction mixture
comprising a base material, (ii) adding said base material to a
second pot containing a metal source compound and optionally an
amine compound, (iii) reacting in said second pot said base
material with said metal source compound and optionally said amine
compound under reaction conditions sufficient to produce a second
reaction mixture comprising said organometallic compound, and (iv)
separating said organometallic compound from said second reaction
mixture; wherein said organometallic compound is represented by the
formula
H.sub.aM(NR.sub.1R.sub.2).sub.x(NR.sub.3H).sub.y(NH.sub.2).sub.z in
which M is a metal or metalloid, each of R.sub.1, R.sub.2 and
R.sub.3 is the same or different and is independently a hydrocarbon
group or a heteroatom-containing group, a is a value from 0 to 3,
preferably 0 or 1, x is a value from 0 to 3, preferably 2 or 3, y
is a value from 0 to 4, preferably 0 or 1, z is a value from 0 to
4, preferably 1 or 2, and a+x+y+z is equal to the oxidation state
of M, provided that at least one of y and z is a value of at least
1. The organometallic compound yield resulting from the process of
this invention can be 60% or greater, preferably 75% or greater,
and more preferably 90% or greater.
[0041] As also indicated above, this invention relates in part to a
process for the production of an organometallic compound comprising
(i) reacting in a first pot a nitrogen-containing compound with an
alkali metal, or an alkali metal-containing compound, or an
alkaline earth metal, or an alkaline earth metal-containing
compound, in the presence of a solvent and under reaction
conditions sufficient to produce a first reaction mixture
comprising a base material, (ii) adding said base material to a
second pot containing a metal source compound and optionally an
amine compound, (iii) reacting in said second pot said base
material with said metal source compound and optionally said amine
compound under reaction conditions sufficient to produce a second
reaction mixture comprising an organometallic compound derivative,
(iv) subjecting said second reaction mixture to reduction or
dehalogenation under conditions sufficient produce a third reaction
mixture comprising said organometallic compound, and (v) separating
said organometallic compound from said third reaction mixture;
wherein said organometallic compound is represented by the formula
:M(NR'.sub.1R'.sub.2).sub.q wherein M is a metal or metalloid,
R'.sub.1 is the same or different and is a hydrocarbon group or a
heteroatom-containing group, R'.sub.2 is the same or different and
is a hydrocarbon group or a heteroatom-containing group; when q is
a value of 2 or greater, R'.sub.1 or R'.sub.2 of one
(NR'.sub.1R'.sub.2) group can be combined with R'.sub.1 or R'.sub.2
of another (NR'.sub.1R'.sub.2) group to form a substituted or
unsubstituted, saturated or unsaturated cyclic group; q is a value
equal to or less than the oxidation state of M, and : represents 2
electrons. The organometallic compound yield resulting from the
process of this invention can be 60% or greater, preferably 75% or
greater, and more preferably 90% or greater.
[0042] In a preferred embodiment, this invention relates to a
process for the production of an organometallic compound comprising
(i) reacting in a first pot a nitrogen-containing compound with an
alkali metal, or an alkali metal-containing compound, or an
alkaline earth metal, or an alkaline earth metal-containing
compound, in the presence of a solvent and under reaction
conditions sufficient to produce a first reaction mixture
comprising a base material, (ii) adding said base material to a
second pot containing a metal source compound and optionally an
amine compound, (iii) reacting in said second pot said base
material with said metal source compound and optionally said amine
compound under reaction conditions sufficient to produce a second
reaction mixture comprising said organometallic compound, and (iv)
separating said organometallic compound from said second reaction
mixture; wherein said organometallic compound is represented by the
formula
H.sub.aSi(NR.sub.1R.sub.2).sub.x(NR.sub.3H).sub.y(NH.sub.2).sub.z
wherein each of each of R.sub.1, R.sub.2 and R.sub.3 is the same or
different and is independently a hydrocarbon group or a
heteroatom-containing group, a is a value from 0 to 3, preferably 0
or 1, x is a value from 0 to 3, preferably 2 or 3, y is a value
from 0 to 4, preferably 0 or 1, z is a value from 0 to 4,
preferably 1 or 2, and a+x+y+z=4, provided that at least one of y
and z is a value of at least 1. The organometallic compound yield
resulting from the process of this invention can be 60% or greater,
preferably 75% or greater, and more preferably 90% or greater.
[0043] In another preferred embodiment, this invention relates in
part to a process for the production of an organometallic compound
comprising (i) reacting in a first pot a nitrogen-containing
compound with an alkali metal, or an alkali metal-containing
compound, or an alkaline earth metal, or an alkaline earth
metal-containing compound, in the presence of a solvent and under
reaction conditions sufficient to produce a first reaction mixture
comprising a base material, (ii) adding said base material to a
second pot containing a metal source compound and optionally an
amine compound, (iii) reacting in said second pot said base
material with said metal source compound and optionally said amine
compound under reaction conditions sufficient to produce a second
reaction mixture comprising an organometallic compound derivative,
(iv) subjecting said second reaction mixture to reduction or
dehalogenation under conditions sufficient produce a third reaction
mixture comprising said organometallic compound, and (v) separating
said organometallic compound from said third reaction mixture;
wherein said organometallic compound is represented by the formula
:Si(NR'.sub.1R'.sub.2).sub.2 wherein R'.sub.1 is the same or
different and is a hydrocarbon group or a heteroatom-containing
group, R'.sub.2 is the same or different and is a hydrocarbon group
or a heteroatom-containing group; R'.sub.1 or R'.sub.2 of one
(NR'.sub.1R'.sub.2) group can be combined with R'.sub.1 or R'.sub.2
of another (NR'.sub.1R'.sub.2) group to form a substituted or
unsubstituted, saturated or unsaturated cyclic group; and :
represents 2 electrons. The organometallic compound yield resulting
from the process of this invention can be 60% or greater,
preferably 75% or greater, and more preferably 90% or greater.
[0044] In the processes described herein, the metal source
compound, e.g., SiCl.sub.4, HSiCl.sub.3, H.sub.2SiCl.sub.2,
tris(dimethylamino)chlorosilane, and the like, starting material
may be selected from a wide variety of compounds known in the art.
The invention herein most prefers metals selected from Si, Ti, Zr,
Hf, V, Nb, Ta, Cr, Mo, W, Al, Ga, Ge, a Lanthanide series element
or an Actinide series element. Illustrative metal source compounds
include, for example, SiCl.sub.4, HSiCl.sub.3, H.sub.2SiCl.sub.2,
HSiCl.sub.3, tris(dimethylamino)chlorosilane, and the like. Other
illustrative metal source compounds include, for example,
SiH.sub.4, SiBr.sub.4, HSiBr.sub.3, SiI.sub.4, HSiI.sub.3, and the
like. The metal source compound starting material can typically be
any compound or pure metal containing the central metal atom.
[0045] In an embodiment, the metal source compound can be
represented by the formula (H).sub.mM(X).sub.n wherein M is Si, Ti,
Zr, Hf, V, Nb, Ta, Cr, Mo, W, Al, Ga, Ge, a Lanthanide series
element or an Actinide series element, X is halide, m is from 0 to
a value less than the oxidation state of M, n is from 1 to a value
equal to the oxidation state of M, and m+n is a value equal to the
oxidation state of M. Preferred metal source compounds include, for
example, tetrachlorosilane, tetrabromosilane, hafnium
tetrachloride, bis(dimethylamino)dichlorosilane,
bis(diethylamino)dichlorosilane, bis(diethylamino)silane,
(N,N'-di-tert-butylethene-1,2-diamino)dichlorosilane,
(N,N'-di-tert-butylethylene-1,2-diamino)dichlorosilane,
(N,N'-diisopropylethene-1,2-diamino)dichlorosilane,
bis(di-tert-butylamino)dichlorosilane, or
bis(di-tert-amylamino)dichlorosilane.
[0046] The concentration of the metal source compound starting
material can vary over a wide range, and need only be that minimum
amount necessary to react with the base material and optionally the
amine compound and to provide the given metal concentration desired
to be employed and which will furnish the basis for at least the
amount of metal necessary for the organometallic compounds of this
invention. In general, depending on the size of the reaction
mixture, metal source compound starting material concentrations in
the range of from about 1 millimole or less to about 10,000
millimoles or greater, should be sufficient for most processes.
[0047] In the processes described herein, the amine compounds may
be selected from a wide variety of compounds known in the art.
Illustrative amine compounds include, for example, dimethylamine,
di-t-amylamine, ammonia, tert-butylamine, and the like. Preferred
amine compound starting materials can be represented by the formula
NR.sub.4R.sub.5R.sub.6 wherein each of R.sub.4, R.sub.5 and R.sub.6
is the same or different and is independently hydrogen, alkyl; a
substituted or unsubstituted, saturated or unsaturated,
hydrocarbon, aromatic hydrocarbon, cycloaliphatic hydrocarbon,
aromatic heterocycle, alkyl halide, silylated hydrocarbon, ether,
polyether, thioether, ester, lactone, amide, amine, polyamine,
nitrile; or mixtures thereof. The amine compounds can include
cyclic and chelating systems. The amine compounds can also include
the HCl salt of amines such as ammonium chloride, dimethylammonium
chloride, and the like. Preferably, each of R.sub.4, R.sub.5 and
R.sub.6 is the same or different and is independently hydrogen,
alkyl, or mixtures thereof. Preferred amine compounds include, for
example, ammonia, ethylamine, t-butylamine, di-tert-butylamine,
di-tert-amylamine, N,N'-di-tert-butylethylene-1,2-diamine,
N,N'-diisopropylethene-1,2-diamine, or
N,N'-di-tert-butylethene-1,2-diamine.
[0048] The concentration of the amine compound starting material
can vary over a wide range, and need only be that minimum amount
necessary to react with the base starting material and metal source
compound. In general, depending on the size of the reaction
mixture, amine compound starting material concentrations in the
range of from about 1 millimole or less to about 10,000 millimoles
or greater, should be sufficient for most processes.
[0049] In the processes described herein, the base starting
material may be selected from a wide variety of compounds known in
the art. Illustrative bases include any base with a pKa greater
than about 10, preferably greater than about 20, and more
preferably greater than about 25. The base material is preferably
LiNH.sub.2, LiNMe.sub.2, lithium amides and the like. Preferred
base starting materials include, for example, lithium amide,
lithium ethylamide, sodium ethylamide, lithium t-butylamide,
lithium di-tert-butylamide, lithium di-tert-amylamide, lithium
N,N'-di-tert-butylethylene-1,2-diamide, lithium
N,N'-diisopropylethene-1,2-diamide, or lithium
N,N'-di-tert-butylethene-1,2-diamide.
[0050] The concentration of the base starting material can vary
over a wide range, and need only be that minimum amount necessary
to react with the amine compound starting material and metal source
compound. In general, depending on the size of the first reaction
mixture, base starting material concentrations in the range of from
about 1 millimole or less to about 10,000 millimoles or greater,
should be sufficient for most processes.
[0051] In one embodiment, the base starting material may be
generated in situ, for example, lithiated amides, lithiated amines,
lithiated diamides, lithiated diamines, and the like. Generating
the base starting material in situ in the reaction vessel
immediately prior to reaction with the metal source compound is
beneficial from a purity standpoint by eliminating the need to
isolate and handle any reactive solids. It is also less
expensive.
[0052] With the in situ generated base starting material in place,
addition of the metal source compound, e.g., SiCl.sub.4, can be
performed through liquid or solid addition, or in some cases more
conveniently as a solvent solution or slurry. Although certain
metal source compounds are moisture sensitive and are used under an
inert atmosphere such as nitrogen, it is generally to a much lower
degree than the amine compounds, for example, lithiated amides,
amines and the like. Furthermore, many metal source compounds are
denser and easier to transfer.
[0053] The base starting material can be prepared from the reaction
of a nitrogen-containing compound and an alkali metal, or an alkali
metal-containing compound, or an alkaline earth metal, or an
alkaline earth metal-containing compound. The base starting
material can be prepared by conventional processes known in the
art.
[0054] The solvent employed in the processes of this invention may
be any saturated and unsaturated hydrocarbons, aromatic
hydrocarbons, aromatic heterocycles, alkyl halides, silylated
hydrocarbons, ethers, polyethers, thioethers, esters, thioesters,
lactones, amides, amines, polyamines, nitriles, silicone oils,
other aprotic solvents, or mixtures of one or more of the above;
more preferably, pentanes, heptanes, octanes, nonanes, decanes,
xylene, tetramethyl benzene, dimethoxyethanes, diglyme, fluorinated
hydrocarbons, and mixtures of one or more of the above; and most
preferably hexanes, ethers, THF, benzene, toluene, and mixtures of
one of more of the above. Any suitable solvent which does not
unduly adversely interfere with the intended reaction can be
employed. Mixtures of one or more different solvents may be
employed if desired. The amount of solvent employed is not critical
to the subject invention and need only be that amount sufficient to
solubilize the reaction components in the reaction mixture. In
general, the amount of solvent may range from about 5 percent by
weight up to about 99 percent by weight or more based on the total
weight of the reaction mixture starting materials.
[0055] Reaction conditions for the processes for the reaction of
the base material, the metal source compound, and optionally the
amine compound, such as temperature, pressure and contact time, may
also vary greatly and any suitable combination of such conditions
may be employed herein. The reaction temperature may be the reflux
temperature of any of the aforementioned solvents, and more
preferably between about -80.degree. C. to about 150.degree. C.,
and most preferably between about 20.degree. C. to about 80.degree.
C. Normally the reaction is carried out under ambient pressure and
the contact time may vary from a matter of seconds or minutes to a
few hours or greater. The reactants can be added to the reaction
mixture or combined in any order. The stir time employed can range
from about 0.1 to about 400 hours, preferably from about 1 to 75
hours, and more preferably from about 4 to 16 hours, for all steps.
In the embodiment of this invention which is carried out in a
single pot, the base material is not separated from the first
reaction mixture prior to reacting with the metal source compound
and optionally the amine compound. In a preferred embodiment, the
metal source compound is added to the first reaction mixture at
ambient temperature or at a temperature greater than ambient
temperature.
[0056] Reaction conditions for the reduction or dehalogenation
step, such as temperature, pressure and contact time, may also vary
greatly and any suitable combination of such conditions may be
employed herein. The reaction temperature may be the reflux
temperature of any of the aforementioned solvents, and more
preferably between about -80.degree. C. to about 150.degree. C.,
and most preferably between about 20.degree. C. to about 80.degree.
C. Normally the reaction is carried out under ambient pressure and
the contact time may vary from a matter of seconds or minutes to a
few hours or greater. The reactants can be added to the reaction
mixture or combined in any order. The stir time employed can range
from about 0.1 to about 400 hours, preferably from about 1 to 75
hours, and more preferably from about 4 to 16 hours, for all steps.
In the embodiment of this invention which is carried out in a
single pot, the base material is not separated from the first
reaction mixture prior to reacting with the metal source compound
and optionally the amine compound. In a preferred embodiment, the
metal source compound is added to the first reaction mixture at
ambient temperature or at a temperature greater than ambient
temperature. Typically, this step can be carried out using a
variety of reagents, preferably an alkali metal (e.g., Na or K) is
utilized.
[0057] The organometallic compounds prepared from the reaction of
the base material, the metal source compound and optionally the
amine compound may be selected from a wide variety of compounds.
For purposes of this invention, organometallic compounds include
compounds having a metal-nitrogen bond. Illustrative organometallic
compounds include, for example, metal amides, metal amines and the
like.
[0058] The organometallic compounds of this invention can also be
prepared by a one pot process. The one pot process is particularly
well-suited for large scale production since it can be conducted
using the same equipment, some of the same reagents and process
parameters that can easily be adapted to manufacture a wide range
of products. The process provides for the synthesis of
organometallic compounds using a process where all manipulations
can be carried out in a single vessel, and which route to the
organometallic compounds does not require the isolation of an
intermediate complex. A one pot process is described in U.S. patent
application Ser. No. 10/678,074, filed Oct. 6, 2003, which is
incorporated herein by reference.
[0059] For organometallic compounds prepared by the processes of
this invention, purification can occur through recrystallization,
more preferably through extraction of reaction residue (e.g.,
hexane) and chromatography, and most preferably through sublimation
and distillation.
[0060] Those skilled in the art will recognize that numerous
changes may be made to the processes described in detail herein,
without departing in scope or spirit from the present invention as
more particularly defined in the claims below.
[0061] Examples of techniques that can be employed to characterize
the organometallic compounds formed by the synthetic methods
described above include, but are not limited to, analytical gas
chromatography, nuclear magnetic resonance, thermogravimetric
analysis, inductively coupled plasma mass spectrometry,
differential scanning calorimetry, vapor pressure and viscosity
measurements.
[0062] Relative vapor pressures, or relative volatility, of
organometallic compound precursors described above can be measured
by thermogravimetric analysis techniques known in the art.
Equilibrium vapor pressures also can be measured, for example by
evacuating all gases from a sealed vessel, after which vapors of
the compounds are introduced to the vessel and the pressure is
measured as known in the art.
[0063] The organometallic compound precursors described herein are
preferably liquid at room temperature, i.e., 20.degree. C., and are
well suited for preparing in-situ powders and coatings. For
instance, a liquid organometallic compound precursor can be applied
to a substrate and then heated to a temperature sufficient to
decompose the precursor, thereby forming a metal or metal oxide
coating on the substrate. Applying a liquid precursor to the
substrate can be by painting, spraying, dipping or by other
techniques known in the art. Heating can be conducted in an oven,
with a heat gun, by electrically heating the substrate, or by other
means, as known in the art. A layered coating can be obtained by
applying an organometallic compound precursor, and heating and
decomposing it, thereby forming a first layer, followed by at least
one other coating with the same or different precursors, and
heating.
[0064] Liquid organometallic compound precursors such as described
above also can be atomized and sprayed onto a substrate.
Atomization and spraying means, such as nozzles, nebulizers and
others, that can be employed are known in the art.
[0065] In preferred embodiments of the invention, an organometallic
compound, such as described above, is employed in gas phase
deposition techniques for forming powders, films or coatings. The
compound can be employed as a single source precursor or can be
used together with one or more other precursors, for instance, with
vapor generated by heating at least one other organometallic
compound or metal complex. More than one organometallic compound
precursor, such as described above, also can be employed in a given
process.
[0066] As indicated above, this invention relates to organometallic
precursor mixtures comprising (i) a first organometallic precursor
compound represented by the formula
H.sub.aM(NR.sub.1R.sub.2).sub.x(NR.sub.3H).sub.y(NH.sub.2).sub.z
wherein M is a metal or metalloid, each of R.sub.1, R.sub.2 and
R.sub.3 is the same or different and is independently a hydrocarbon
group or a heteroatom-containing group, a is a value from 0 to 3,
preferably 0 or 1, x is a value from 0 to 3, preferably 2 or 3, y
is a value from 0 to 4, preferably 0 or 1, z is a value from 0 to
4, preferably 1 or 2, and a+x+y+z is equal to the oxidation state
of M, provided that at least one of y and z is a value of at least
1, and (ii) one or more different organometallic precursor
compounds. (e.g., a hafnium-containing, tantalum-containing or
molybdenum-containing organometallic precursor compound).
[0067] As also indicated above, this invention relates to
organometallic precursor compound mixtures comprising (i) a first
organometallic precursor compound represented by the formula
:M(NR'.sub.1R'.sub.2).sub.q wherein M is a metal or metalloid,
R'.sub.1 is the same or different and is a hydrocarbon group or a
heteroatom-containing group, R'.sub.2 is the same or different and
is a hydrocarbon group or a heteroatom-containing group; when q is
a value of 2 or greater, R'.sub.1 or R'.sub.2 of one
(NR'.sub.1R'.sub.2) group can be combined with R'.sub.1 or R'.sub.2
of another (NR'.sub.1R'.sub.2) group to form a substituted or
unsubstituted, saturated or unsaturated cyclic group; q is a value
equal to or less than the oxidation state of M, and : represents 2
electrons, and (ii) one or more different organometallic precursor
compounds (e.g., a hafnium-containing, tantalum-containing or
molybdenum-containing organometallic precursor compound).
[0068] In a preferred embodiment, this invention relates to
organometallic precursor mixture comprising (i) a first
organometallic precursor compound represented by the formula
H.sub.aSi(NR.sub.1R.sub.2).sub.x(NR.sub.3H).sub.y(NH.sub.2).sub.z
wherein each of R.sub.1, R.sub.2 and R.sub.3 is the same or
different and is independently a hydrocarbon group or a
heteroatom-containing group, a is a value from 0 to 3, preferably 0
or 1, x is a value from 0 to 3, preferably 2 or 3, y is a value
from 0 to 4, preferably 0 or 1, z is a value from 0 to 4,
preferably 1 or 2, and a+x+y+z=4, provided that at least one of y
and z is a value of at least 1, and (ii) one or more different
organometallic precursor compounds (e.g., a hafnium-containing,
tantalum-containing or molybdenum-containing organometallic
precursor compound).
[0069] In another preferred embodiment, this invention relates to
organometallic precursor compound mixtures comprising (i) a first
organometallic precursor compound represented by the formula
:Si(NR'.sub.1R'.sub.2).sub.2 wherein R'.sub.1 is the same or
different and is a hydrocarbon group or a heteroatom-containing
group, R'.sub.2 is the same or different and is a hydrocarbon group
or a heteroatom-containing group; R'.sub.1 or R'.sub.2 of one
(NR'.sub.1R'.sub.2) group can be combined with R'.sub.1 or R'.sub.2
of another (NR'.sub.1R'.sub.2) group to form a substituted or
unsubstituted, saturated or unsaturated cyclic group; and :
represents 2 electrons, and (ii) one or more different
organometallic precursor compounds (e.g., a hafnium-containing,
tantalum-containing or molybdenum-containing organometallic
precursor compound).
[0070] Deposition can be conducted in the presence of other gas
phase components. In an embodiment of the invention, film
deposition is conducted in the presence of at least one
non-reactive carrier gas. Examples of non-reactive gases include
inert gases, e.g., nitrogen, argon, helium, as well as other gases
that do not react with the organometallic compound precursor under
process conditions. In other embodiments, film deposition is
conducted in the presence of at least one reactive gas. Some of the
reactive gases that can be employed include but are not limited to
hydrazine, oxygen, hydrogen, air, oxygen-enriched air, ozone
(O.sub.3), nitrous oxide (N.sub.2O), water vapor, organic vapors,
ammonia and others. As known in the art, the presence of an
oxidizing gas, such as, for example, air, oxygen, oxygen-enriched
air, O.sub.3, N.sub.2O or a vapor of an oxidizing organic compound,
favors the formation of a metal oxide film.
[0071] As indicated above, this invention also relates in part to a
method for producing a film, coating or powder. The method includes
the step of decomposing at least one organometallic compound
precursor, thereby producing the film, coating or powder, as
further described below. More particularly, this invention relates
in part to a method for producing a film, coating or powder by
decomposing an organometallic precursor compound represented by the
formula
H.sub.aM(NR.sub.1R.sub.2).sub.x(NR.sub.3H).sub.y(NH.sub.2).sub.z
wherein M is a metal or metalloid, each of R.sub.1, R.sub.2 and
R.sub.3 is the same or different and is independently a hydrocarbon
group or a heteroatom-containing group, a is a value from 0 to 3,
preferably 0 or 1, x is a value from 0 to 3, preferably 2 or 3, y
is a value from 0 to 4, preferably 0 or 1, z is a value from 0 to
4, preferably 1 or 2, and a+x+y+z is equal to the oxidation state
of M, provided that at least one of y and z is a value of at least
1, thereby producing the film, coating or powder. Typically, the
decomposing of said organometallic precursor compound is thermal,
chemical, photochemical or plasma-activated.
[0072] As also indicated above, this invention relates in part to a
method for producing a film, coating or powder by decomposing an
organometallic precursor compound represented by the formula
:M(NR'.sub.1R'.sub.2).sub.q wherein M is a metal or metalloid,
R'.sub.1 is the same or different and is a hydrocarbon group or a
heteroatom-containing group, R'.sub.2 is the same or different and
is a hydrocarbon group or a heteroatom-containing group; when a is
a value of 2 or greater, R'.sub.1 or R'.sub.2 of one
(NR'.sub.1R'.sub.2) group can be combined with R'.sub.1 or R'.sub.2
of another (NR'.sub.1R'.sub.2) group to form a substituted or
unsubstituted, saturated or unsaturated cyclic group; a is a value
equal to or less than the oxidation state of M, and : represents 2
electrons, thereby producing the film, coating or powder.
Typically, the decomposing of said organometallic precursor
compound is thermal, chemical, photochemical or
plasma-activated.
[0073] In a preferred embodiment, this invention relates to a
method for producing a film, coating or powder by decomposing an
organometallic precursor compound represented by the formula
H.sub.aSi(NR.sub.1R.sub.2).sub.x(NR.sub.3H).sub.y(NH.sub.2).sub.z
wherein each of R.sub.1, R.sub.2 and R.sub.3 is the same or
different and is independently a hydrocarbon group or a
heteroatom-containing group, a is a value from 0 to 3, preferably 0
or 1, x is a value from 0 to 3, preferably 2 or 3, y is a value
from 0 to 4, preferably 0 or 1, z is a value from 0 to 4,
preferably 1 or 2, and a+x+y+z=4, provided that at least one of y
and z is a value of at least 1, thereby producing the film, coating
or powder. Typically, the decomposing of said organometallic
precursor compound is thermal, chemical, photochemical or
plasma-activated.
[0074] In another preferred embodiment, this invention relates in
part to a method for producing a film, coating or powder by
decomposing an organometallic precursor compound represented by the
formula :Si(NR'.sub.1R'.sub.2).sub.2 wherein R'.sub.1 is the same
or different and is a hydrocarbon group or a heteroatom-containing
group, R'.sub.2 is the same or different and is a hydrocarbon group
or a heteroatom-containing group; R'.sub.1 or R'.sub.2 of one
(NR'.sub.1R'.sub.2) group can be combined with R'.sub.1 or R'.sub.2
of another (NR'.sub.1R'.sub.2) group to form a substituted or
unsubstituted, saturated or unsaturated cyclic group; and :
represents 2 electrons, thereby producing the film, coating or
powder. Typically, the decomposing of said organometallic precursor
compound is thermal, chemical, photochemical or
plasma-activated.
[0075] Deposition methods described herein can be conducted to form
a film, powder or coating that includes a single metal or a film,
powder or coating that includes a single metal oxide. Mixed films,
powders or coatings also can be deposited, for instance mixed metal
oxide films. A mixed metal oxide film can be formed, for example,
by employing several organometallic precursors, at least one of
which being selected from the organometallic compounds described
above.
[0076] Gas phase film deposition can be conducted to form film
layers of a desired thickness, for example, in the range of from
about 1 nm to over 1 mm. The precursors described herein are
particularly useful for producing thin films, e.g., films having a
thickness in the range of from about 10 nm to about 100 nm. Films
of this invention, for instance, can be considered for fabricating
metal electrodes, in particular as n-channel metal electrodes in
logic, as capacitor electrodes for DRAM applications, and as
dielectric materials.
[0077] The method also is suited for preparing layered films,
wherein at least two of the layers differ in phase or composition.
Examples of layered film include metal-insulator-semiconductor, and
metal-insulator-metal.
[0078] In an embodiment, the invention is directed to a method that
includes the step of decomposing vapor of an organometallic
compound precursor described above, thermally, chemically,
photochemically or by plasma activation, thereby forming a film on
a substrate. For instance, vapor generated by the compound is
contacted with a substrate having a temperature sufficient to cause
the organometallic compound to decompose and form a film on the
substrate.
[0079] The organometallic compound precursors can be employed in
chemical vapor deposition or, more specifically, in metalorganic
chemical vapor deposition processes known in the art. For instance,
the organometallic compound precursors described above can be used
in atmospheric, as well as in low pressure, chemical vapor
deposition processes. The compounds can be employed in hot wall
chemical vapor deposition, a method in which the entire reaction
chamber is heated, as well as in cold or warm wall type chemical
vapor deposition, a technique in which only the substrate is being
heated.
[0080] The organometallic compound precursors described above also
can be used in plasma or photo-assisted chemical vapor deposition
processes, in which the energy from a plasma or electromagnetic
energy, respectively, is used to activate the chemical vapor
deposition precursor. The compounds also can be employed in
ion-beam, electron-beam assisted chemical vapor deposition
processes in which, respectively, an ion beam or electron beam is
directed to the substrate to supply energy for decomposing a
chemical vapor deposition precursor. Laser-assisted chemical vapor
deposition processes, in which laser light is directed to the
substrate to affect photolytic reactions of the chemical vapor
deposition precursor, also can be used.
[0081] The method of the invention can be conducted in various
chemical vapor deposition reactors, such as, for instance, hot or
cold-wall reactors, plasma-assisted, beam-assisted or
laser-assisted reactors, as known in the art.
[0082] Examples of substrates that can be coated employing the
method of the invention include solid substrates such as metal
substrates, e.g., Al, Ni, Ti, Co, Pt, Ta; metal silicides, e.g.,
TiSi.sub.2, CoSi.sub.2, NiSi.sub.2; semiconductor materials, e.g.,
Si, SiGe, GaAs, InP, diamond, GaN, SiC; insulators, e.g.,
SiO.sub.2, Si.sub.3N.sub.4, HfO.sub.2, Ta.sub.2O.sub.5,
Al.sub.2O.sub.3, barium strontium titanate (BST); barrier
materials, e.g., TiN, TaN; or on substrates that include
combinations of materials. In addition, films or coatings can be
formed on glass, ceramics, plastics, thermoset polymeric materials,
and on other coatings or film layers. In preferred embodiments,
film deposition is on a substrate used in the manufacture or
processing of electronic components. In other embodiments, a
substrate is employed to support a low resistivity conductor
deposit that is stable in the presence of an oxidizer at high
temperature or an optically transmitting film.
[0083] The method of this invention can be conducted to deposit a
film on a substrate that has a smooth, flat surface. In an
embodiment, the method is conducted to deposit a film on a
substrate used in wafer manufacturing or processing. For instance,
the method can be conducted to deposit a film on patterned
substrates that include features such as trenches, holes or vias.
Furthermore, the method of the invention also can be integrated
with other steps in wafer manufacturing or processing, e.g.,
masking, etching and others.
[0084] Chemical vapor deposition films can be deposited to a
desired thickness. For example, films formed can be less than 1
micron thick, preferably less than 500 nanometer and more
preferably less than 200 nanometers thick. Films that are less than
50 nanometer thick, for instance, films that have a thickness
between about 1 and about 20 nanometers, also can be produced.
[0085] Organometallic compound precursors described above also can
be employed in the method of the invention to form films by atomic
layer deposition (ALD) or atomic layer nucleation (ALN) techniques,
during which a substrate is exposed to alternate pulses of
precursor, oxidizer and inert gas streams. Sequential layer
deposition techniques are described, for example, in U.S. Pat. No.
6,287,965 and in U.S. Pat. No. 6,342,277. The disclosures of both
patents are incorporated herein by reference in their entirety.
[0086] For example, in one ALD cycle, a substrate is exposed, in
step-wise manner, to: a) an inert gas; b) inert gas carrying
precursor vapor; c) inert gas; and d) oxidizer, alone or together
with inert gas. In general, each step can be as short as the
equipment will permit (e.g. milliseconds) and as long as the
process requires (e.g. several seconds or minutes). The duration of
one cycle can be as short as milliseconds and as long as minutes.
The cycle is repeated over a period that can range from a few
minutes to hours. Film produced can be a few nanometers thin or
thicker, e.g., 1 millimeter (mm).
[0087] The method of the invention also can be conducted using
supercritical fluids. Examples of film deposition methods that use
supercritical fluid that are currently known in the art include
chemical fluid deposition; supercritical fluid transport-chemical
deposition; supercritical fluid chemical deposition; and
supercritical immersion deposition.
[0088] Chemical fluid deposition processes, for example, are well
suited for producing high purity films and for covering complex
surfaces and filling of high-aspect-ratio features. Chemical fluid
deposition is described, for instance, in U.S. Pat. No. 5,789,027.
The use of supercritical fluids to form films also is described in
U.S. Pat. No. 6,541,278 B2. The disclosures of these two patents
are incorporated herein by reference in their entirety.
[0089] In an embodiment of the invention, a heated patterned
substrate is exposed to one or more organometallic compound
precursors, in the presence of a solvent, such as a near critical
or supercritical fluid, e.g., near critical or supercritical
CO.sub.2. In the case of CO.sub.2, the solvent fluid is provided at
a pressure above about 1000 psig and a temperature of at least
about 30.degree. C.
[0090] The precursor is decomposed to form a metal film on the
substrate. The reaction also generates organic material from the
precursor. The organic material is solubilized by the solvent fluid
and easily removed away from the substrate. Metal oxide films also
can be formed, for example by using an oxidizing gas.
[0091] In an example, the deposition process is conducted in a
reaction chamber that houses one or more substrates. The substrates
are heated to the desired temperature by heating the entire
chamber, for instance, by means of a furnace. Vapor of the
organometallic compound can be produced, for example, by applying a
vacuum to the chamber. For low boiling compounds, the chamber can
be hot enough to cause vaporization of the compound. As the vapor
contacts the heated substrate surface, it decomposes and forms a
metal or metal oxide film. As described above, an organometallic
compound precursor can be used alone or in combination with one or
more components, such as, for example, other organometallic
precursors, inert carrier gases or reactive gases.
[0092] In a system that can be used in producing films by the
method of the invention, raw materials can be directed to a
gas-blending manifold to produce process gas that is supplied to a
deposition reactor, where film growth is conducted. Raw materials
include, but are not limited to, carrier gases, reactive gases,
purge gases, precursor, etch/clean gases, and others. Precise
control of the process gas composition is accomplished using
mass-flow controllers, valves, pressure transducers, and other
means, as known in the art. An exhaust manifold can convey gas
exiting the deposition reactor, as well as a bypass stream, to a
vacuum pump. An abatement system, downstream of the vacuum pump,
can be used to remove any hazardous materials from the exhaust gas.
The deposition system can be equipped with in-situ analysis system,
including a residual gas analyzer, which permits measurement of the
process gas composition. A control and data acquisition system can
monitor the various process parameters (e.g., temperature,
pressure, flow rate, etc.).
[0093] The organometallic compound precursors described above can
be employed to produce films that include a single metal or a film
that includes a single metal oxide. Mixed films also can be
deposited, for instance mixed metal oxide films. Such films are
produced, for example, by employing several organometallic
precursors. Metal films also can be formed, for example, by using
no carrier gas, vapor or other sources of oxygen.
[0094] Films formed by the methods described herein can be
characterized by techniques known in the art, for instance, by
X-ray diffraction, Auger spectroscopy, X-ray photoelectron emission
spectroscopy, atomic force microscopy, scanning electron
microscopy, and other techniques known in the art. Resistivity and
thermal stability of the films also can be measured, by methods
known in the art.
[0095] Atomic layer deposition and chemical vapor deposition of
silicates and silicides can be useful for many next generation
materials (e.g., hafnium silicates for dielectrics, tantalum
silicon nitride for electrode or barrier). The versatility of the
organometallic precursor compounds of this invention, which can be
more reactive silicon precursors and deposit both mixed
silicate/silicides and nanolaminate structures, would be highly
beneficial.
[0096] Various modifications and variations of this invention will
be obvious to a worker skilled in the art and it is to be
understood that such modifications and variations are to be
included within the purview of this application and the spirit and
scope of the claims.
Examples
Synthesis of Si(N(CH.sub.3).sub.2).sub.3(NH.sub.2)
[0097] Under an inert atmosphere (nitrogen), 2 molar equivalents of
LiNH.sub.2 were added to 1 molar equivalent of
Si(N(CH.sub.3).sub.2).sub.3Cl in tetrahydrofuran solvent. The
reaction was stirred at a temperature of 25.degree. C. for a period
of 48 hours. Monitoring of the reaction was done by gas
chromatography/mass spectrometry in which both
Si(N(CH.sub.3).sub.2).sub.3Cl and
Si(N(CH.sub.3).sub.2).sub.3(NH.sub.2) parent ions were observed.
Once conversion was complete, the solvent was removed, and the
product was isolated by distillation as a clear colorless liquid.
.sup.1H NMR (300 MHz, C.sub.6D.sub.6): 2.52 (s, 18H), 0.25 (br t,
2H, 50 Hz). GC-MS (m/z, %): 176 (100), 132 (100), 116 (33).
Atomic Layer Deposition of SiO.sub.2 comparing
Si(N(CH.sub.3).sub.2).sub.4 and
Si(N(CH.sub.3).sub.2).sub.3(NH.sub.2) Precursors
[0098] The utility of Si(N(CH.sub.3).sub.2).sub.3(NH.sub.2) was
evaluated by comparing performance to the known precursor
Si(N(CH.sub.3).sub.2).sub.4. An experiment using atomic layer
deposition of SiO.sub.2 was undertaken, utilizing growth rates as
the basis for comparison. The conditions of the experiment were as
follows: silicon substrates, wafer temperature at 330.degree. C.,
pressure of 5 torr, precursor flow about 0.7 standard cubic
centimeters per minute (based on thermogravimetric analysis
vaporization rates), 4 step cycles,
precursor/purge/co-reactant/purge, 10/20/10/20 seconds. Argon was
utilized as the carrier gas. The co-reactant was an Ar/O.sub.2
plasma (10 Watts load). Thickness was measured by variable angle
spectroscopic ellipsometry. Minimal thickness contributions related
to growth of SiO.sub.2 due to O.sub.2 plasma alone were taken into
account. The results showed that
Si(N(CH.sub.3).sub.2).sub.3(NH.sub.2) produced an SiO.sub.2 film at
over twice the growth rate of Si(N(CH.sub.3).sub.2).sub.4 (0.054
nanometers/cycle vs. 0.023 nanometers/cycle).
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