U.S. patent application number 12/058200 was filed with the patent office on 2008-10-16 for metal precursor solutions for chemical vapor deposition.
This patent application is currently assigned to AIR PRODUCTS AND CHEMICALS, INC.. Invention is credited to William Franklin Burgoyne, Gauri Sankar Lal, Xinjian Lei, John Anthony Thomas Norman, Liam Quinn, Daniel P. Spence, Michael Ulman.
Application Number | 20080254218 12/058200 |
Document ID | / |
Family ID | 39531292 |
Filed Date | 2008-10-16 |
United States Patent
Application |
20080254218 |
Kind Code |
A1 |
Lei; Xinjian ; et
al. |
October 16, 2008 |
Metal Precursor Solutions For Chemical Vapor Deposition
Abstract
Metal source containing precursor liquid solutions for chemical
vapor deposition processes, including atomic layer deposition, for
fabricating conformal metal-containing films on substrates are
described. More specifically, the metal source precursor liquid
solutions are comprised of (i) at least one metal complex selected
from .beta.-diketonates, .beta.-ketoiminates, .beta.-diiminates,
alkyl metal, metal carbonyl, alkyl metal carbonyl, aryl metal, aryl
metal carbonyl, cyclopentadienyl metal, cyclopentadienyl metal
isonitrile, cyclopentadienyl metal nitrile, cyclopentadienyl metal
carbonyl, metal alkoxide, metal ether alkoxide, and metal amides
wherein the ligand can be monodentate, bidentate and multidentate
coordinating to the metal atom and the metal is selected from group
2 to 14 elements, and (ii) a solvent selected from organic amides
including linear amides and cyclic amides for such metal source
containing precursors.
Inventors: |
Lei; Xinjian; (Vista,
CA) ; Quinn; Liam; (Carlsbad, CA) ; Norman;
John Anthony Thomas; (Encinitas, CA) ; Burgoyne;
William Franklin; (Bethlehem, PA) ; Lal; Gauri
Sankar; (Whitehall, PA) ; Ulman; Michael;
(Mertztown, PA) ; Spence; Daniel P.; (San Diego,
CA) |
Correspondence
Address: |
AIR PRODUCTS AND CHEMICALS, INC.;PATENT DEPARTMENT
7201 HAMILTON BOULEVARD
ALLENTOWN
PA
181951501
US
|
Assignee: |
AIR PRODUCTS AND CHEMICALS,
INC.
Allentown
PA
|
Family ID: |
39531292 |
Appl. No.: |
12/058200 |
Filed: |
March 28, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60911970 |
Apr 16, 2007 |
|
|
|
Current U.S.
Class: |
427/248.1 ;
106/1.05 |
Current CPC
Class: |
C23C 16/18 20130101;
C23C 16/16 20130101 |
Class at
Publication: |
427/248.1 ;
106/1.05 |
International
Class: |
C23C 18/44 20060101
C23C018/44 |
Claims
1. A metal source precursor solution having utility for chemical
vapor deposition or atomic layer deposition in the manufacture of
semiconductor device structures, said metal source precursor
solution consisting essentially of: (i) at least one metal
coordination complex comprising a metal coordinatively bound to at
least one ligand in a stable complex; and, (ii) an organic amide
solvent for said metal coordination complex.
2. The metal source precursor solution of claim 1 wherein the metal
coordination complex is selected from the group consisting of: (a)
Metal .beta.-diketonates having the formula: ##STR00008## wherein M
is a metal selected from Group 2 to 14 and wherein R.sup.1-3 are
linear, branched or cyclic independently selected from the groups
consisting of hydrogen, C.sub.1-10 alkyl, C.sub.1-10 alkenyl,
C.sub.1-10 alkynyl, C.sub.3-10 alkylsilyl, C.sub.5-C.sub.10
cycloaliphatic, C.sub.6-12 aryl, and fluorinated C.sub.1-10 alkyl;
wherein x is an integer 2, 3, or 4 depending on the valence of M;
(b) Metal .beta.-ketoiminates having the formula: ##STR00009##
wherein M is a metal selected from Group 2 to 14 and wherein
R.sup.1-3 are linear, branched or cyclic independently selected
from the groups consisting of hydrogen, C.sub.1-10 alkyl,
C.sub.1-10 alkenyl, C.sub.1-10 alkynyl, C.sub.3-10 alkylsilyl,
C.sub.5-C.sub.10 cycloaliphatic, C.sub.6-12 aryl, and fluorinated
C.sub.1-10 alkyl; R.sup.4 is linear or branched selected from the
group consisting of hydrogen, C.sub.1-10 alkyl, C.sub.1-10 alkenyl,
C.sub.1-10 alkynyl, C.sub.5-C.sub.10 cycloaliphatic, C.sub.6-12
aryl, C.sub.3-10 alkylsilyl, and fluorinated C.sub.1-10 alkyl; x is
an integer 2, 3, or 4 depending on the valence of M; (c) Metal
.beta.-diiminates having the formula: ##STR00010## wherein M is
selected from Group 2 to 13, and wherein R.sup.1-3 are linear,
branched or cyclic independently selected from the groups
consisting of hydrogen, C.sub.1-10 alkyl, linear C.sub.1-10
alkenyl, C.sub.1-10 alkynyl, C.sub.5-C.sub.10 cycloaliphatic,
C.sub.6-12 aryl, C.sub.3-10 alkylsilyl, and fluorinated C.sub.1-10
alkyl; wherein x is the integer 2, 3, or 4; R.sup.4-5 are linear,
branched or cyclic independently selected from the groups
consisting of hydrogen, C.sub.1-10 alkyl, C.sub.5-C.sub.10
cycloaliphatic, C.sub.6-12 aryl, C.sub.3-10 alkylsilyl and
fluorinated C.sub.1-10 alkyl; and x is an integer 2, 3, or 4
depending on the valence of M; (d) Metal Alkoxy .beta.-diketonates
having the formula: ##STR00011## wherein M is a metal ion selected
from Group 4 and 5 metals and wherein R.sup.1-3 are linear,
branched or cyclic independently selected from the groups
consisting of C.sub.1-10 alkyl, C.sub.1-10 alkenyl, C.sub.1-10
alkynyl, C.sub.5-C.sub.10 cycloaliphatic, C.sub.6-12 aryl,
C.sub.3-10 alkylsilyl and fluorinated C.sub.1-10 alkyl; R.sup.4 is
linear or branched independently selected from the group consisting
of C.sub.1-10 alkyl, C.sub.1-10 alkenyl, C.sub.1-10 alkynyl,
C.sub.5-C.sub.10 cycloaliphatic, C.sub.6-12 aryl, C.sub.3-10
alkylsilyl and fluorinated C.sub.1-10 alkyl; and m and n are at
least 1 and the sum of m plus n is equal to the valence of the
metal M; (e) Alkyl Metal .beta.-diketonates having the formula:
##STR00012## wherein M is a metal ion selected from Group 8, 9, and
10 metals including iron, cobalt, nickel, ruthenium, rhodium,
palladium, osmium, iridium, platinum; wherein R.sup.1-3 are linear,
branched or cyclic selected from the groups consisting of
C.sub.1-10 alkyl, C.sub.1-10 alkenyl, C.sub.1-10 alkynyl,
C.sub.5-C.sub.10 cycloaliphatic, C.sub.6-12 aryl, C.sub.3-10
alkylsilyl and fluorinated C.sub.1-10 alkyl; wherein R.sup.4 is
linear, branched or cyclic selected from the groups consisting of
C.sub.1-10 alkyl, C.sub.1-10 alkenyl, C.sub.1-10 alkynyl,
C.sub.5-C.sub.10 cycloaliphatic, C.sub.6-10 cycloalkene, C.sub.6-12
cycloalkyne, C.sub.6-12 aryl, C.sub.3-10 alkylsilyl and fluorinated
C.sub.1-10 alkyl; m and n are each at least 1 and the sum of m plus
n is equal to the valence of the metal M and n is equal to the
valence of the metal M if R.sup.4 is a neutral ligand; (f) Metal
Alkoxy .beta.-ketoiminates having the formula: ##STR00013## wherein
M is a metal ion selected from Group 4 and 5 metals; R.sup.1-5 are
linear, branched or cyclic independently selected from the groups
consisting of hydrogen, C.sub.1-10 alkyl, C.sub.1-10 alkenyl,
C.sub.1-10 alkynyl, C.sub.5-C.sub.10 cycloaliphatic, C.sub.6-12
aryl, C.sub.3-10 alkylsilyl and fluorinated C.sub.1-10 alkyl; and m
and n are at least 1 and the sum of m plus n is equal to the
valence of the metal M; (g) Metal .beta.-ketoiminates with the
formula: ##STR00014## wherein M is a metal ion selected from Group
11 metals; wherein R.sup.12 are linear, branched or cyclic
independently selected from the groups consisting of hydrogen,
C.sub.1-10 alkyl, C.sub.1-10 alkenyl, C.sub.1-10 alkynyl,
C.sub.5-C.sub.10 cycloaliphatic, C.sub.6-12 aryl, C.sub.3-10
alkylsilyl and fluorinated C.sub.1-10 alkyl or halogen; R.sup.34
are linear or branched independently selected from the group
consisting of C.sub.1-4 linear or branched alkyl, C.sub.1-4 linear
or branched alkenyl, C.sub.1-4 linear or branched alkynyl and
fluorinated C.sub.1-4 alkyl, preferably R.sup.4 is a 2 to 3 carbon
atom linkage, thus making a five- or six-member coordinating ring
to the metal center; R.sup.5-6 are linear, branched or cyclic
independently selected from the group consisting of C.sub.1-10
alkyl, C.sub.1-10 alkenyl, C.sub.1-10 alkynyl, C.sub.5-C.sub.10
cycloaliphatic, C.sub.6-12 aryl, fluorinated C.sub.1-10 alkyl or
connected to form a ring containing carbon, oxygen, or nitrogen
atoms; and Y is either an oxygen, or a nitrogen substituted with a
hydrogen, C.sub.1-6 alkyl or C.sub.6-10 aryl group (h) Metal alkyl
having the formula: MR.sup.1.sub.xR.sup.2.sub.y wherein M is a
metal selected from Group 2 to 14 wherein R.sup.1 and R.sup.2 are
linear, branched or cyclic independently selected from the groups
consisting of hydrogen, C.sub.1-10 alkyl, C.sub.1-10 alkenyl,
C.sub.1-10 alkynyl, C.sub.5-C.sub.10 cycloaliphatic, C.sub.6-12
aryl, C.sub.3-10 alkylsilyl, fluorinated C.sub.1-10 alkyl,
cyclopendienyl (Cp) and alkylcyclopendienyl; x is an integer 0, 1,
2, 3, or 4; y is an integer 0, 1, 2, 3, or 4 and x+y=the valence of
M; (i) Alkyl metal carbonyl having the formula: (CO).sub.yMR.sub.x
wherein M is a metal selected from Group 2 to 14; R is linear,
branched or cyclic independently selected from the groups
consisting of hydrogen, C.sub.1-10 alkyl, C.sub.1-10 alkenyl,
C.sub.1-10 alkynyl, C.sub.5-C.sub.10 cycloaliphatic, C.sub.6-12
aryl, C.sub.3-10 alkylsilyl, fluorinated C.sub.1-10 alkyl,
cyclopendienyl (Cp) and alkylcyclopendienyl and mixtures thereof; x
is the integer 2, 3, or 4; y is the integer 1, 2, 3, or 4 and x=the
valence of M; (j) Metal carbonyl with the formula:
M.sub.x(CO).sub.y wherein M is a metal selected from Group 8 to 10,
x is the integer 1, 2, or 3 and y is in an integer from 4 to 12,
where x times the valence of the metal=2y; (k) Metal alkoxide with
the formula: M(OR)n wherein M is a metal selected from Group 2 to
14; R is linear, branched or cyclic independently selected from the
groups consisting of hydrogen, C.sub.1-10 alkyl, C.sub.1-10
alkenyl, C.sub.1-10 alkynyl, C.sub.5-C.sub.10 cycloaliphatic,
C.sub.6-12 aryl, C.sub.3-10 alkylsilyl and fluorinated C.sub.1-10
alkyl, and mixtures thereof; and n is the integer 2, 3, 4, or 5
equal to the valence of M; and (l) Metal amides with the formula:
M(NR.sup.1R.sup.2)n wherein M is a metal selected from Group 2 to
14; wherein R.sup.1-2 are linear, branched or cyclic independently
selected from the groups consisting of hydrogen, C.sub.1-10 alkyl,
C.sub.1-10 alkenyl, C.sub.1-10 alkynyl, C.sub.5-C.sub.10
cycloaliphatic, C.sub.6-12 aryl, C.sub.3-10 alkylsilyl and
fluorinated C.sub.1-10 alkyl; and n is the integer 2, 3, 4, or 5
equal to the valence of M;
3. The metal source precursor solution of claim 2 and wherein the
ligand of the metal coordination complexes is either (a) identical
to result in degenerative ligand exchange, or (b) resistant to
non-degenerative ligand exchange in relation to one another.
4. The metal source precursor solution of claim 2 wherein the
solvent comprises an amide represented by the formula: RCONR'R''
wherein R and R' are linear or branched alkyl having from 1-10
carbon atoms or connected to form a cyclic group (CH.sub.2).sub.n,
n is from 4-6, and R'' is alkyl having from 1 to 4 carbon atoms and
cycloalkyl.
5. The metal source precursor solution of claim 4 wherein the
solvent is selected from the group consisting of
N-methyl-2-pyrrolidinone, N-ethyl 2-pyrrolidinone and N-cyclohexyl
2-pyrrolidinone.
6. The metal source precursor solution of claim 4 wherein the metal
of the metal coordination complex is selected from the group
consisting of formulas (a), (b), and (c), and the metal is selected
from the group consisting of Mg, Ca, Sr, Ba, Y, La, Ce, Sm, Tb, Er,
Yb, Lu, Ti, Zr, Hf, Fe, Co, Ni, Ru, Ir, Rh, Cu, Al, Sn, and Pb.
7. The metal source precursor solution of claim 6 wherein the
ligand is selected from the group consisting of acetylacetonate
(acac), hexafluoroacetylacetonate (hfacac);
trifluoroacetylacetonate (tfacac); tetramethylheptanedionate (thd);
fluorodimethyloctanedionate (fod); and
heptafluoro-dimethyloctanedionate.
8. The metal source precursor solution of claim 7 wherein the metal
coordination complex is selected from the group consisting of
Sr(thd).sub.2, Ba(thd).sub.2, Co(acac).sub.2, Ni(acac).sub.2,
Cu(acac).sub.2, Ru(thd).sub.3, La(thd).sub.3, Y(thd).sub.3,
Ti(thd).sub.4, Hf(thd).sub.4, and Zr(thd).sub.4.
9. The metal source precursor solution of claim 2 wherein the metal
coordination complex is selected from the group consisting of the
formulas (d) and (e) and the metal is selected from the group
consisting of titanium, zirconium, hafnium, vanadium, niobium, and
tantalum.
10. The metal source precursor solution of claim 2 wherein the
metal coordination complex is represented by the formula (k) and is
selected from the group consisting of Ti(.sup.iPrO).sub.4,
Hf(OBu.sup.t).sub.4, Zr(OBu.sup.t).sub.4, and
Ta.sub.2(OEt).sub.10.
11. The metal source precursor solution of claim 2 wherein metal
coordination complex is represented by the formula (l) and is
selected from the group consisting of Cp.sub.2Ru(CO).sub.2,
(1,3-cyclohexdiene)Ru(CO).sub.3, CpCo(CO).sub.2, CpRe(CO).sub.3,
and .sup.iPrCpRe(CO).sub.3.
12. The metal source precursor solution of claim 2 where metal
coordination complex is represented by the formula (j) and is
selected from the group consisting of Ru.sub.3(CO).sub.12,
W(CO).sub.6, Mo(CO).sub.6, CO.sub.2(CO).sub.8, and
Ni(CO).sub.4.
13. The metal source precursor solution of claim 2 wherein the
metal coordination complex is
bis(2,2,6,6-tetramethyl-3,5-heptanedionato)(1,5-cyclo-octadiene)ruthenium-
(II).
14. The metal source precursor solution of claim 2 wherein the
metal coordination complex is represented by the formula (h) and is
selected from the group consisting of CoCp.sub.2, SrCp.sub.2,
Sr(.sup.iPrCp).sub.2, Sr(.sup.iPr.sub.3 Cp).sub.2, BaCp.sub.2,
Ba(.sup.iPrCp).sub.2, Ba(.sup.iPr.sub.3 Cp).sub.2, RuCp.sub.2,
Ru(MeCp)(EtCp), Ru(EtCp).sub.2, NiCp.sub.2, Cp.sub.2HfMe.sub.2, and
Cp.sub.2ZrMe.sub.2.
15. The metal source precursor solution of claim 2 wherein the
metal coordination complex is represented by the formula (l) and is
selected from the group consisting of
tetrakis(dimethylamino)titanium (TDMAT),
tetrakis(diethylamino)titanium (TDEAT),
tetrakis(ethylmethyl)titanium (TEMAT),
tetrakis(dimethylamino)zirconium (TDMAZ),
tetrakis(diethylamino)zirconium (TDEAZ),
tetrakis(ethylmethyl)zirconium (TEMAZ),
tetrakis(dimethylamino)hafnium (TDMAH),
tetrakis(diethylamino)hafnium (TDEAH), tetrakis(ethylmethyl)hafnium
(TEMAH), tert-butylimino tri(diethylamino)tantalum (TBTDET),
tert-butylimino tri(dimethylamino)tantalum (TBTDMT),
tert-butylimino tri(ethylmethylamino)tantalum (TBTEMT), ethyllimino
tri(diethylamino)tantalum (EITDET), ethyllimino
tri(dimethylamino)tantalum (EITDMT), ethyllimino
tri(ethylmethylamino)tantalum (EITEMT), tert-amylimino
tri(dimethylamino)tantalum (TAIMAT), tert-amylimino
tri(diethylamino)tantalum, pentakis(dimethylamino)tantalum,
tert-amylimino tri(ethylmethylamino)tantalum,
bis(tert-butylimino)bis(dimethylamino)tungsten (BTBMW),
bis(tert-butylimino)bis(diethylamino)tungsten, and
bis(tert-butylimino)bis(ethylmethylamino)tungsten.
16. The metal source precursor solution of claim 1 wherein the
metal coordination complex is selected from the group consisting of
Cu(CF.sub.3C(O)CHC(NCH.sub.2CH.sub.2OSiMe.sub.2C.sub.2H.sub.3)CF.sub.3),
Cu(CF.sub.3C(O)CHC(NCH.sub.2CH.sub.2OSiMe.sub.2C.sub.2H.sub.3)Me),
Cu(MeC(O)CHC(NCH.sub.2CH(Me)OSiMe.sub.2C.sub.2H.sub.3)Me),
Cu(MeC(O)CHC(NCH.sub.2CH.sub.2OSiMe.sub.2C.sub.2H.sub.3)Me),
Cu(MeC(O)CHC(NCH.sub.2CH.sub.2N(Me)SiMe.sub.2C.sub.2H.sub.3)Me),
Cu(MeC(O)CHC(NCH(Et)CH.sub.2OSiMe.sub.2C.sub.2H.sub.3)Me).
17. A process for the vapor deposition employing a metal-containing
precursor solution for forming a conformal metal-containing film
wherein said metal-containing precursor solution is vaporized in a
chamber and the metal deposited onto a substrate, which comprises
using the metal source precursor solution of claim 1 as said
metal-containing precursor solution.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This patent application claims the benefit of U.S.
Provisional Patent Application Ser. No. 60/911,970 filed 16 Apr.
2007.
BACKGROUND OF THE INVENTION
[0002] The semiconductor fabrication industry continues to use
metal source containing precursors for chemical vapor deposition
processes including atomic layer deposition for fabricating
conformal metal-containing films on substrates such as silicon,
silicon oxide, metal nitride, metal oxide and other
metal-containing layers using these metal source containing
precursors. In the fabrication process, a particularly advantageous
way of delivering multiple source containing precursors is to
employ neat liquid source containing liquid metal precursors or
solutions of metal source precursors dissolved in a solvent, flash
to vaporize the mixture, and then deliver the resulting vapors to
the reactor. If in the fabrication process the reactions convert
the metal source containing precursor to an insoluble or
non-volatile product, or to a material of different chemical or
physical properties, the elements contained in that product may not
reach the substrate and the stoichiometry of the deposited film may
not be correct.
[0003] In certain instances, such problems can be avoided sometimes
by using identical ligands coordinated to the metals to make ligand
exchange a degenerate reaction (i.e., where the exchanging ligand
is identical to the original ligand). The foregoing problems also
may be encountered where the precursor is provided in a liquid
solution and the solvent contains moieties which react with the
metal or ligands of the precursor to produce undesirable reaction
by-products.
[0004] The following references are illustrative of metal source
containing precursor solutions for use in preparing conformal
metal-containing films: U.S. Pat. No. 5,820,664; U.S. Pat. No.
6,225,237; U.S. Pat. No. 6,984,591; US2006/0269667; Lee, D.-J.,
S.-W. Kang and S.-W. Rhee (2001). "Chemical vapor deposition of
ruthenium oxide thin films from Ru(tmhd).sub.3 using direct liquid
injection." Thin Solid Films 413: 237; U.S. Pat. No. 6,111,122;
Moshnyaga, V., I. Khoroshun, A. Sidorenko, P. Petrenko, A.
Weidinger, M. Zeitler, B. Rauschenbach, R. Tidecks and K. Samwer
(1999). "Preparation of rare-earth manganite-oxide thin films by
metalorganic aerosol deposition technique." Applied Physics Letters
74(19): 2842-2844; U.S. Pat. No. 5,900,279; U.S. Pat. No.
5,916,359; and JP 06234779.
BRIEF SUMMARY OF THE INVENTION
[0005] The present invention generally relates to an improvement in
metal source containing precursor solutions suitable for use in
chemical vapor deposition processes, including cyclic chemical
vapor deposition as well as atomic layer deposition, for
fabricating conformal metal-containing films on substrates and to
such processes. More specifically, the metal source precursor
solutions are comprised of (i) at least one metal coordination
complex including a metal, to which is coordinatively bound to at
least one ligand in a stable complex and (ii) a solvent comprised
of an organic amide for such metal source containing precursors.
Preferably the ligand for metal complex is selected from the group
consisting of: .beta.-diketonates, .beta.-ketoiminates,
.beta.-ketoesters, alkyl, carbonyl, alkylcyclopentadineyl, and
alkoxy.
[0006] Some of the advantages which may be available through the
use of these solutions include the following:
[0007] an ability to provide metal source precursor compositions in
liquid solution form to simultaneously deliver the constituent
metal(s) to a deposition locus such as a chemical vapor deposition
or atomic layer deposition chamber;
[0008] an ability to provide solutions which are resistant to
deleterious ligand exchange reactions;
[0009] an ability to provide a solution containing a high boiling
linear or cyclic organic amide;
[0010] an ability to stabilize a metal complex in both liquid and
gas phase via coordinating the organic amide to the metal center,
an ability to promote the vaporization of the metal complex via a
direct liquid injection device; and,
[0011] an ability to tune the physical properties of the precursor
solution such as viscosity for easy delivery.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a Thermo Gravimetric Analysis (TGA) of 1.0 M
solution of titanium isopropoxide in N-methyl-2-pyrrolidinone.
[0013] FIG. 2 is a TGA of 0.1M solution of
tris(2,2,6,6-tetramethyl-3,5-heptanedionate)lanthanum in
N-methyl-2-pyrrolidinone.
[0014] FIG. 3 shows TGAs of solutions of
tetrakis(ethylmethylamino)zirconium (TEMAZ) in
N-methyl-2-pyrrolidinone: A (10% NMP in TEMAZ); B (40% NMP in
TEMAZ); C (50% NMP in TEAM).
[0015] FIG. 4 is a TGA of 0.3M of tetrakis(dimethylamine)hafnium in
N-methyl-2-pyrrolidinone.
[0016] FIG. 5 shows TGAs of solutions of Cu-KI3 in
N-methyl-2-pyrrolidinone: 1 (8% NMP in KI3); 2 (12% NMP in KI-3); 3
(27% NMP in KI3).
DETAILED DESCRIPTION OF THE INVENTION
[0017] In reference to the above, the broadly based metal source
precursor solutions are comprised of (i) at least one metal
coordination complex including a metal, to which is coordinatively
bound to at least one ligand in a stable complex. Representative
metal complexes include .beta.-diketonates, .beta.-ketoiminates,
.beta.-diiminates, alkyl metal, metal carbonyl, alkyl metal
carbonyl, aryl metal, aryl metal carbonyl, cyclopentadienyl metal,
alkylcyclopentadienyl metal, cyclopentadienyl metal isonitrile,
cyclopentadienyl metal nitrile, carbonyl cyclopentadienyl metal,
metal alkoxide, metal ether alkoxide, and metal amides. The ligand
can be monodentate, bidentate and multidentate coordinating to the
metal atom and the metal is selected from group 2 to 14 elements.
Generally the valence of the metal is from 2 to 5.
[0018] Variations of the above metal source containing precursors
are represented by the generalized formulas:
[0019] (a) Metal .beta.-diketonates having the formula:
##STR00001##
[0020] wherein M is selected from Group 2 to 14, e.g., those having
a valence from 2 to 5 and specific examples of metals include Mg,
Ca, Sr, Ba, Y, La, Ce, Sm, Tb, Er, Yb, Lu, Ti, Zr, Hf, Fe, Co, Ni,
Ru, Ir, Rh, Cu, Al, Sn, and Pb; wherein R.sup.1-3 are linear,
branched, or cyclic independently selected from the groups
consisting of hydrogen, C.sub.1-10 alkyl, C.sub.1-10 alkenyl,
C.sub.3-10 alkylsilyl, C.sub.1-10 alkynyl, C.sub.5-C.sub.10
cycloaliphatic, C.sub.6-12 aryl, and fluorinated C.sub.1-10 alkyl;
wherein x is the integer 2, 3, or 4 based upon the valence of the
metal.
[0021] Illustrative .beta.-diketonate ligands employed in metal
source complexes of the present invention include: acetylacetonate
or more specifically 2,4-pentanedionate (acac),
hexafluoroacetylacetonate or more specifically
1,1,1,5,5,5-hexafluoro-2,4-pentanedionate (hfacac);
trifluoroacetylacetonate or more specifically
1,1,1-trifluoro-2,4-pentanedionate (tfacac);
tetramethylheptanedionate or more specifically
2,2,6,6-tetramethyl-3,5-heptanedionate (thd);
fluorodimethyloctanedionate or more specifically
1,1,1,2,2,3,3-heptafluoro-7,7-dimethyl-4,6-octanedionate (fod); and
heptafluoro-dimethyloctanedionate. Exemplary metal complexes
include Sr(thd).sub.2, Ba(thd).sub.2, Co(acac).sub.2,
Ni(acac).sub.2, Cu(acac).sub.2, Ru(thd).sub.3, La(thd).sub.3,
Y(thd).sub.3, Ti(thd).sub.4, Hf(thd).sub.4, and Zr(thd).sub.4.
[0022] (b) Metal .beta.-ketoiminates having the formula:
##STR00002##
[0023] wherein M is selected from Group 2 to 14, and specific
examples of metals include Mg, Ca, Sr, Ba, Y, La, Ce, Sm, Tb, Er,
Yb, Lu, Ti, Zr, Hf, Fe, Co, Ni, Ru, Ir, Rh, Cu, Al, Sn, and Pb;
wherein R.sup.1-3 are linear, branched or cyclic independently
selected from the groups consisting of hydrogen, C.sub.1-10 alkyl,
C.sub.1-10 alkenyl, C.sub.1-10 alkynyl, C.sub.3-10 alkylsilyl,
C.sub.5-C.sub.10 cycloaliphatic, C.sub.6-12 aryl, and fluorinated
C.sub.1-10 alkyl; wherein x is the integer 2, 3, or 4 consistent
with the valence of M; R.sup.4 is linear, branched or cyclic
selected from the group consisting of hydrogen, C.sub.1-10 alkyl,
C.sub.1-10 alkenyl, C.sub.1-10 alkynyl, C.sub.3-10 alkylsilyl,
C.sub.5-C.sub.10 cycloaliphatic, C.sub.6-12 aryl, and fluorinated
C.sub.1-10 alkyl.
[0024] (c) Metal .beta.-diiminates having the formula:
##STR00003##
[0025] wherein M is selected from Group 2 to 13, and specific
examples of metals include Mg, Ca, Sr, Ba, Y, La, Ce, Sm, Tb, Er,
Yb, Lu, Ti, Zr, Hf, Fe, Co, Ni, Ru, Ir, Rh, Cu, Al, Sn, and Pb;
wherein R.sup.1-3 are linear, branched or cyclic independently
selected from the groups consisting of hydrogen, C.sub.1-10 alkyl,
C.sub.1-10 alkenyl, C.sub.1-10 alkynyl, C.sub.3-10 alkylsilyl,
C.sub.5-C.sub.10 cycloaliphatic, C.sub.6-12 aryl, and fluorinated
C.sub.1-10 alkyl; wherein x is the integer 2, 3, or 4. R.sup.4-5
also can contain unsaturation bonds and are linear, branched or
cyclic independently selected from the groups consisting of
hydrogen, C.sub.1-10 alkyl, C.sub.1-10 alkenyl, C.sub.1-10 alkynyl,
C.sub.5-C.sub.10 cycloaliphatic, C.sub.6-12 aryl, and fluorinated
C.sub.1-10 alkyl.
[0026] (d) Metal Alkoxy .beta.-diketonates having the formula:
##STR00004##
[0027] wherein M is a metal ion selected from Group 4 and 5 metals
including titanium, zirconium, hafnium, vanadium, niobium, and
tantalum; wherein R.sup.1-3 are linear, branched or cyclic
independently selected from the groups consisting of C.sub.1-10
alkyl, C.sub.1-10 alkenyl, C.sub.1-10 alkynyl, C.sub.3-10
alkylsilyl, C.sub.5-C.sub.10 cycloaliphatic, C.sub.6-12 aryl, and
fluorinated C.sub.1-10 alkyl R.sup.4 is linear, branched or cyclic
selected from the group consisting of C.sub.1-10 alkyl, C.sub.1-10
alkenyl, C.sub.1-10 alkynyl, C.sub.3-10 alkylsilyl,
C.sub.5-C.sub.10 cycloaliphatic, C.sub.6-12 aryl, and fluorinated
C.sub.1-10 alkyl; wherein m and n are at least 1 and the sum of m
plus n is equal to the valence of the metal M. Exemplary metal
complexes include Ti(thd).sub.2(OBu.sup.t).sub.2,
Hf(thd).sub.2(OBu.sup.t).sub.2, and
Zr(thd).sub.2(OBu.sup.t).sub.2.
[0028] (e) Alkyl Metal .beta.-diketonates having the formula:
##STR00005##
[0029] wherein M is a metal ion selected from Group 8, 9, and 10
metals including iron, cobalt, nickel, ruthenium, rhodium,
palladium, osmium, iridium, platinum; wherein R.sup.1-3 are liner,
branched or cyclic selected from the groups consisting of
C.sub.1-10 alkyl, C.sub.1-10 alkenyl, C.sub.1-10 alkynyl,
C.sub.3-10 alkylsilyl, C.sub.5-C.sub.10 cycloaliphatic, C.sub.6-12
aryl, and fluorinated C.sub.1-10 alkyl; wherein R.sup.4 is linear,
branched or cyclic selected from the groups consisting of
C.sub.1-10 alkyl, C.sub.1-10 alkenyl, C.sub.1-10 alkynyl,
C.sub.5-C.sub.10 cycloaliphatic, C.sub.6-10 cycloalkene, C.sub.6-12
cycloalkyne, C.sub.6-12 aryl, and fluorinated C.sub.1-10 alkyl;
wherein m and n are at least 1 and the sum of m plus n is equal to
the valence of the metal M and n is equal to the valence of the
metal M if R.sup.4 is a neutral ligand. Exemplary metal complexes
but not limited
bis(2,2,6,6-tetramethyl-3,5-heptanedionato)(1,5-cyclo-octadiene)ruthenium-
(II).
[0030] (f) Metal Alkoxy .beta.-ketoiminates with the formula:
##STR00006##
[0031] wherein M is a metal ion selected from Group 4 and 5 metals
including titanium, zirconium, hafnium, vanadium, niobium, and
tantalum; wherein R.sup.1-5 are linear, branched or cyclic
independently selected from the group consisting of hydrogen,
C.sub.1-10 alkyl, C.sub.1-10 alkenyl, C.sub.1-10 alkynyl,
C.sub.3-10 alkylsilyl, C.sub.5-C.sub.10 cycloaliphatic, C.sub.6-12
aryl, and fluorinated C.sub.1-10 alkyl; wherein m and n are at
least 1 and the sum of m plus n is equal to the valence of the
metal M.
[0032] (g) Metal .beta.-ketoiminates with the formula:
##STR00007##
[0033] wherein M is a metal ion selected from Group 11 metals
including copper, silver, and gold; wherein R.sup.1-2 are linear,
branched or cyclic independently selected from the groups
consisting of hydrogen, C.sub.1-10 alkyl, C.sub.1-10 alkenyl,
C.sub.1-10 alkynyl, C.sub.3-10 alkylsilyl, C.sub.5-C.sub.10
cycloaliphatic, C.sub.6-12 aryl, and fluorinated C.sub.1-10 alkyl
or halogen; R.sup.3-4 are linear or branched independently selected
from the groups consisting of C.sub.1-6 alkyl, C.sub.1-6 alkenyl,
C.sub.1-6 alkynyl and fluorinated C.sub.1-6 alkyl, preferably
R.sup.4 is a 2 to 4 carbon atom linkage; R.sup.5-6 are linear,
branched or cyclic independently selected from the groups
consisting of C.sub.1-10 alkyl, C.sub.1-10 alkenyl, C.sub.1-10
alkynyl, C.sub.5-C.sub.10 cycloaliphatic, C.sub.6-12 aryl,
fluorinated C.sub.1-10 alkyl or connected to form a ring containing
carbon, oxygen, or nitrogen atoms; X is either a carbon or a
silicon, and Y is either an oxygen, or a nitrogen substituted with
a hydrogen, C.sub.1-6 alkyl or C.sub.6-10 aryl group. Exemplary
metal complexes include
Cu(CF.sub.3C(O)CHC(NCH.sub.2CH.sub.2OSiMe.sub.2C.sub.2H.sub.3)CF.sub.3),
Cu(CF.sub.3C(O)CHC(NCH.sub.2CH.sub.2OSiMe.sub.2C.sub.2H.sub.3)Me),
Cu(MeC(O)CHC(NCH.sub.2CH(Me)OSiMe.sub.2C.sub.2H.sub.3)Me),
Cu(MeC(O)CHC(NCH.sub.2CH.sub.2OSiMe.sub.2C.sub.2H.sub.3)Me),
Cu(MeC(O)CHC(NCH.sub.2CH.sub.2N(Me)SiMe.sub.2C.sub.2H.sub.3)Me),
Cu(MeC(O)CHC(NCH(Et)CH.sub.2OSiMe.sub.2C.sub.2H.sub.3)Me).
[0034] (h) Metal alkyl having the formula:
MR.sup.1.sub.xR.sup.2.sub.y
[0035] wherein M is selected from Group 2 to 14 where specific
examples of metals include Mg, Ca, Sr, Ba, Y, La, Ce, Sm, Tb, Er,
Yb, Lu, Fe, Co, Ni, Ru, Ir, Rh, Cu, Al, and Pb; wherein R.sup.1 and
R.sup.2 are linear, branched or cyclic independently selected from
the groups consisting of hydrogen, C.sub.1-10 alkyl, C.sub.1-10
alkenyl, C.sub.1-10 alkynyl, C.sub.5-C.sub.10 cycloaliphatic,
C.sub.3-10 alkylsilyl, C.sub.6-12 aryl, and fluorinated C.sub.1-10
alkyl, cyclopendienyl (Cp) and alkylcyclopendienyl; and wherein x
is the integer 0, 1, 2, 3, or 4; y is the integer 0, 1, 2, 3, or 4
and x+y=the valence of M; and Me represents --CH.sub.3. Exemplary
metal complexes include CoCp.sub.2, SrCp.sub.2,
Sr(.sup.iPrCp).sub.2, Sr(.sup.iPr.sub.3 Cp).sub.2, BaCp.sub.2,
Ba(.sup.iPrCp).sub.2, Ba(.sup.iPr.sub.3 Cp).sub.2, RuCp.sub.2,
Ru(EtCp).sub.2, Ru(MeCp)(EtCp), Ru(DMPD)(EtCp), NiCp.sub.2,
Cp.sub.2HfMe.sub.2, and Cp.sub.2ZrMe.sub.2.
[0036] (i) Alkyl metal carbonyl having the formula:
(CO).sub.yMR.sub.x
[0037] wherein M is selected from Group 2 to 14 where specific
examples of metals include Mg, Ca, Sr, Ba, Y, La, Ce, Sm, Tb, Er,
Yb, Lu, Fe, Co, Ni, Ru, Ir, Rh, Cu, Al, and Pb; wherein R is
linear, branched or cyclic selected from the groups consisting of
C.sub.1-10 alkyl, C.sub.1-10 alkenyl, C.sub.1-10 alkynyl,
C.sub.5-C.sub.10 cycloaliphatic, C.sub.3-10 alkylsilyl, C.sub.6-12
aryl, and fluorinated C.sub.1-10 alkyl, cyclopendienyl (Cp) and
alkylcyclopendienyl; wherein x=2, 3, 4; y=1, or, 2, or 3, or 4 and
x=the valence of M. Exemplary metal complexes include
Cp.sub.2Ru(CO).sub.2, (1,3-cyclohexdiene)Ru(CO).sub.3,
CpRe(CO).sub.3, CpCo(CO).sub.2 and .sup.iPrCpRe(CO).sub.3.
[0038] (j) Metal carbonyl with the formula:
M.sub.x(CO).sub.y
[0039] wherein M is selected from Group 8 to 10 where specific
examples of metals include Fe, Co, Ni, Ru, Ir, and Rh; wherein x is
an integer 1, 2, or 3; y is an integer 4 to 12. Exemplary metal
complexes include Ru.sub.3(CO).sub.12, W(CO).sub.6, Mo(CO).sub.6,
CO.sub.2(CO).sub.8, and Ni(CO).sub.4.
[0040] (k) Metal alkoxide with the formula:
M(OR)n
[0041] wherein M is selected from Group 2 to 14 where specific
examples of metals include Mg, Ca, Sr, Ba, Y, La, Ce, Sm, Tb, Er,
Yb, Lu, Fe, Co, Ni, Ru, Ir, Rh, Cu, Al, and Pb; wherein R is
linear, branched or cyclic selected from the groups consisting of
C.sub.1-10 alkyl, C.sub.1-10 alkenyl, C.sub.1-10 alkynyl,
C.sub.5-C.sub.10 cycloaliphatic, C.sub.6-12 aryl, and fluorinated
C.sub.1-10 alkyl; wherein n is an integer 2, 3, 4 or 5, comprising
the valence of M. Exemplary metal complexes include
Ti(.sup.iPrO).sub.4, Hf(OBu.sup.t).sub.4, Zr(OBu.sup.t).sub.4, and
Ta.sub.2(OEt).sub.10.
[0042] (i) Metal amides with the formula:
M(NR.sup.1R.sup.2)n
[0043] wherein M is selected from Group 2 to 14 where specific
examples of metals include Mg, Ca, Sr, Ba, Y, La, Ce, Sm, Tb, Er,
Yb, Lu, Fe, Co, Ni, Ru, Ir, Rh, Cu, Al, and Pb; wherein R.sup.1-2
are liner, branched or cyclic independently selected from the
groups consisting of C.sub.1-10 alkyl, C.sub.1-10 alkenyl,
C.sub.1-10 alkynyl, C.sub.3-10 alkylsilyl, C.sub.5-C.sub.10
cycloaliphatic, C.sub.6-12 aryl, and fluorinated C.sub.1-10 alkyl;
wherein n is the integer 2, 3, 4, or 5, comprising the valence of
M.
[0044] Exemplary metal complexes include
tetrakis(dimethylamino)titanium (TDMAT),
tetrakis(diethylamino)titanium (TDEAT),
tetrakis(ethylmethyl)titanium (TEMAT),
tetrakis(dimethylamino)zirconium (TDMAZ),
tetrakis(diethylamino)zirconium (TDEAZ),
tetrakis(ethylmethyl)zirconium (TEMAZ),
tetrakis(dimethylamino)hafnium (TDMAH),
tetrakis(diethylamino)hafnium (TDEAH), tetrakis(ethylmethyl)hafnium
(TEMAH), tert-butylimino tri(diethylamino)tantalum (TBTDET),
tert-butylimino tri(dimethylamino)tantalum (TBTDMT),
tert-butylimino tri(ethylmethylamino)tantalum (TBTEMT), ethyllimino
tri(diethylamino)tantalum (EITDET), ethyllimino
tri(dimethylamino)tantalum (EITDMT), ethyllimino
tri(ethylmethylamino)tantalum (EITEMT), tert-amylimino
tri(dimethylamino)tantalum (TAIMAT), tert-amylimino
tri(diethylamino)tantalum, pentakis(dimethylamino)tantalum,
tert-amylimino tri(ethylmethylamino)tantalum,
bis(tert-butylimino)bis(dimethylamino)tungsten (BTBMW),
bis(tert-butylimino)bis(diethylamino)tungsten,
bis(tert-butylimino)bis(ethylmethylamino)tungsten.
[0045] Summarizing, the ligand groups of the metal source
containing precursor complexes in the broad practice of the present
invention may be variously substituted to produce a wide variety of
materials to optimize volatility, stability and film purity.
Preferably, when the metal source precursor comprises two or more
metal source containing precursor complexes, the ligands of the
various metal source containing precursor complexes should be
either: (a) identical, to result in degenerative ligand exchange
(wherein any ligand exchange involves replacement of the ligand
group by the same type ligand from another constituent of the
multicomponent solution); or, (b) resistant to any detrimental
non-degenerative ligand exchange in relation to one another, which
would substantially impair or preclude the efficacy of the metal
source complex for its intended purpose.
[0046] The metal source containing precursors generally are
selected for solution applications on the basis of the following
criteria: (i) the metal centers in the coordinated complexes should
be as coordinatively saturated as possible, and in such respect
multidentate ligands are preferred which occupy multiple
coordination sites in the source precursor complex; (ii) the
ligands preferably comprise sterically bulky groups such as
isopropyl, t-butyl, and neopentyl, which prevent intermolecular
interaction of the metal centers and thus hinder ligand exchange
reaction and (iii) each of the individual metal source precursors
in the solution should have a suitable vapor pressure
characteristic, e.g., a vapor pressure of at least 0.001 Torr at
the temperature and pressure conditions involved in their
volatilization.
[0047] The solvent medium employed in formulating the metal source
precursor solutions in accordance with the present invention is the
organic amide class of the form, RCONR'R'', wherein R and R' are
linear or branched alkyl having from 1-10 carbon atoms or R and R'
can be connected to form a cyclic group (CH.sub.2).sub.n, wherein n
is from 4-6, preferably 5, and R'' is alkyl having from 1 to 4
carbon atoms and cycloalkyl. N-methyl, N-ethyl and N-cyclohexyl
2-pyrrolidinones are examples of the preferred solvents of the
organic amide class.
[0048] The metal source precursor solutions of the present
invention may be readily employed in chemical vapor deposition
(CVD) applications including atomic layer deposition (ALD) for
forming a metal-containing film on a substrate by the steps of
volatilizing the metal source precursor liquid solution to yield a
metal source vapor, and contacting the metal source vapor with the
substrate, to deposit the metal-containing film thereon.
[0049] The following examples illustrate the preparation of the
metal-containing complexes as precursor solutions in
metal-containing film deposition processes and their use in a
chemical vapor deposition process.
EXAMPLE 1
Preparation of 1.0M solution of titanium isopropoxide in
N-methyl-2-pyrrolidinone
[0050] To a 2 mL vial, a faint yellow orange solution of titanium
isopropoxide (0.10 g, 0.35 mmol) and 0.35 mL
N-methyl-2-pyrrolidinone (NMP) was prepared. The solution was kept
at room temperature over night and did not show any visible change.
FIG. 1 is a TGA of the 1.M solution of titanium isopropoxide in
N-methyl-2-pyrrolidinone, suggesting a smooth vaporization process
in the temperature range of 20 to 400.degree. C. This vaporization
behavior suggests the solution can be employed either via bubbling
or direct liquid injection for chemical vapor deposition or atomic
vapor deposition.
EXAMPLE 2
Preparation of 0.1M solution of
tris(2,2,6,6-tetramethyl-3,5-heptanedionate)lanthanum in
N-methyl-2-pyrrolidinone
[0051] To a 2 mL vial, a clear solution of La(thd).sub.3) (0.05 g,
0.07 mmol) and 0.78 mL NMP was prepared. FIG. 2 is a TGA of 0.1M
solution of tris(2,2,6,6-tetramethyl-3,5-heptanedionate)lanthanum
in N-methyl-2-pyrrolidinone, indicating there are two vaporization
processes, the first is mainly for NMP and the second
tris(2,2,6,6-tetramethyl-3,5-heptanedionate)lanthanum. This
vaporization behavior suggests the solution can be only employed
via direct liquid injection for chemical vapor deposition or atomic
vapor deposition.
EXAMPLE 3
Preparation of solutions of tetrakis(ethylmethylamino)zirconium in
N-methyl-2-pyrrolidinone
[0052] Three solutions of tetrakis(ethylmethylamino)zirconium
(TEMAZ) in NMP were prepared according to Table 1. All are clear
yellow solutions.
TABLE-US-00001 TABLE 1 TEMAZ Sample (g) NMP (g) A 0.2 1.8 B 0.24
0.35 C 0.2 0.2
[0053] FIG. 3 shows TGA diagrams of the solutions, suggesting that
direct liquid injection with a lower concentration is
preferred.
EXAMPLE 4
Preparation of 0.3M of tetrakis(dimethylamino)hafnium in
N-methyl-2-pyrrolidinone
[0054] The procedure of Example 1 is followed in preparing the
above solution. FIG. 4 is a TGA graph of a 0.3M yellow solution of
tetrakis(dimethylamino)hafnium (TDMAH) in N-methyl-2-pyrrolidinone,
suggesting that direct liquid injection with lower concentration is
preferred.
EXAMPLE 5
Preparation of 1.0M solution of tetrakis(diethylamino)zirconium in
N-cyclohexyl-2-pyrrolidinone
[0055] To a 2 mL vial, a clear orange solution of
tetrakis(diethylamino)zirconium (TDEAZ) (0.05 g, 0.07 mmol) and
0.27 g of N-cyclohexyl-2-pyrrolidinone was prepared. The TGA graph
indicates the solution is volatile and can be used as precursor
source in a CVD or ALD process.
EXAMPLE 6
Preparation of 0.01M solution of tungsten carbonyl in
N-methyl-2-pyrrolidinone
[0056] To a 2 mL vial, a clear yellow solution of tungsten carbonyl
(0.10 g, 0.17 mmol) and 12 g of N-methyl-2-pyrrolidinone was
prepared. The TGA graph indicates the solution is volatile and can
be used as precursor source for CVD or ALD.
EXAMPLE 7
Preparation of 0.01M solution of
bis(2,2,6,6-tetramethyl-3,5-heptanedionato)(1,5-cyclo-octadiene)ruthenium-
(II) in N-methyl-2-pyrrolidinone
[0057] To a 2 mL vial, a clear orange solution of
bis(2,2,6,6-tetramethyl-3,5-heptanedionato)(1,5-cyclo-octadiene)ruthenium-
(II) (0.10 g, 0.28 mmol) and 20 g of N-methyl-2-pyrrolidinone was
prepared. The TGA graph indicates the solution is volatile and can
be used as precursor source for CVD or ALD.
EXAMPLE 8
Preparation of solutions of
(CF.sub.3C(O)CHC(NCH.sub.2CH.sub.2OSiMe.sub.2C.sub.2H.sub.3)CF.sub.3)Cu
in N-methyl-2-pyrrolidinone
[0058] Table 2 below shows the weights of the copper metal complex
Cu-KI3 (i.e.,
(CF.sub.3C(O)CHC(NCH.sub.2CH.sub.2OSiMe.sub.2C.sub.2H.sub.3)CF.sub-
.3)Cu) mixed with dry deoxygenated NMP solvent under nitrogen.
After thoroughly mixing, three solutions 1, 2 and 3 were
individually tested in a TGA/DSC (Differential Scanning
Calorimetry) apparatus.
[0059] In this system, a small sample of 1, 2 or 3 was placed in a
microbalance and a steady flow of nitrogen passed over the sample
as it was steadily heated. Evaporation is registered as weight
loss, manifest as a smooth curve down to almost complete
evaporation. Since all three samples do not show two stages of
evaporation per sample, i.e., the solvent evaporates first and then
the copper complex evaporates, it is evident that these mixtures
represent excellent blends for Direct Liquid Injection (DLI) type
delivery for a CVD or ALD process. The TGA graphs are shown in FIG.
5.
TABLE-US-00002 TABLE 2 NMP added to Cu--KI3 Sample Weight of
Cu--KI3 Weight of NMP Wt % age NMP added 1 0.787 g 0.063 g 8.0 2
0.284 g 0.035 g 12.0 3 0.145 g 0.039 g 27.0
EXAMPLE 9
Preparation of 1M solution of bis(ethylcyclopentadienyl)ruthenium
in N-methyl-2-pyrrolidinone
[0060] To a 2 mL vial, an amber solution of
bis(ethylcyclopentadienyl)ruthenium (1.00 g, 2.88 mmol) and 2.97 g
of N-methyl-2-pyrrolidinone was prepared. The TGA graph indicates
the solution is completely vaporized, leaving no residue.
EXAMPLE 10
Preparation of 0.25M solution of
bis(n-propyltetramethylcyclopentadienyl)barium in
N-methyl-2-pyrrolidinone
[0061] To a 2 mL vial, a clear yellow solution of
bis(n-propyltetramethyl cyclopentadienyl)barium (0.14 g, 0.30 mmol)
and 1.24 g of N-methyl-2-pyrrolidinone was prepared. The TGA graph
shows the solution is more volatile than pure
bis(n-propyltetramethylcyclopentadienyl)barium, suggesting NMP
enhances the vaporization of
bis(n-propyltetramethylcyclopentadienyl)barium.
EXAMPLE 11
Preparation of 0.5M solution of
tris(i-propylcyclopentadienyl)lanthanum in
N-methyl-2-pyrrolidinone
[0062] To a 2 mL vial, a clear solution of
tris(i-propylcyclopentadienyl)lanthanum (0.21 g, 0.46 mmol) and
0.94 g of N-methyl-2-pyrrolidinone was prepared. The TGA graph
indicates the solution is volatile and can be used as precursor
source for CVD or ALD.
EXAMPLE 12
Preparation of 0.38M solution of
bis(2,2,6,6-tetramethyl-3,5-heptanedionate)strontium in
N-methyl-2-pyrrolidinone
[0063] To a 2 mL vial, a yellow solution of
bis(2,2,6,6-tetramethyl-3,5-heptanedionate)strontium (0.23 g, 0.51
mmol) and 1.38 g of N-methyl-2-pyrrolidinone was prepared. The TGA
graph shows the solution is more volatile than pure
bis(2,2,6,6-tetramethyl-3,5-heptanedionate)strontium, suggesting
NMP enhances the vaporization of
bis(2,2,6,6-tetramethyl-3,5-heptanedionate)strontium.
EXAMPLE 13
Preparation of 0.25M solution of
bis(2,2,6,6-tetramethyl-3,5-heptanedionate)barium in
N-methyl-2-pyrrolidinone
[0064] To a 2 mL vial, a foggy white solution of
bis(2,2,6,6-tetramethyl-3,5-heptanedionate)barium (0.14 g, 0.28
mmol) and 1.14 g of N-methyl-2-pyrrolidinone was prepared. The TGA
graph indicates the solution is volatile and can be used as
precursor source for CVD or ALD.
EXAMPLE 14
CVD Copper Using a Solution of Precursor KI3 (i.e.,
Cu(CF.sub.3C(O)CHC(NCH.sub.2CH.sub.2OSiMe.sub.2C.sub.2H.sub.3)CF.sub.3))
Dissolved in NMP Delivered by DLI Mode with Formic Acid Vapor as
Reagent Gas
[0065] Process details: A Gartek single wafer CVD reactor fitted
with a Direct Liquid Injector (DLI) system was used to individually
process ruthenium and titanium coated silicon wafers at a process
chamber pressure of 1 Torr and wafer temperature of 150.degree. C.
The copper precursor was utilized as a 3:1 by weight ratio of KI3
dissolved in dry N-methylpyrolidone (NMP) and injected into the
vaporizer at a rate of 41 mg/min using an evaporation temperature
of 100.degree. C. with an argon carrier gas flow of 250 sccm.
Formic acid vapor was delivered by the DLI of 82 mg of liquid
formic acid/min using an evaporation temperature of 65.degree. C.
with an argon carrier gas flow rate of 100 sccm. Run time was 30
minutes.
[0066] Results: Ruthenium: 427.5 nm of copper (as confirmed by EDX
(energy dispersive x-ray) analysis) were deposited to give, after
correcting for the ruthenium underlayer conductivity, a resistivity
of 2.6 .mu..OMEGA.cm.
[0067] Results: Titanium nitride: 386.7 nm of copper (as confirmed
by EDX analysis) were deposited to give, after correcting for the
titanium nitride underlayer, a resistivity of 2.3
.mu..OMEGA.cm.
* * * * *