U.S. patent application number 14/162944 was filed with the patent office on 2014-05-22 for resin film forming sheet for chip, and method for manufacturing semiconductor chip.
This patent application is currently assigned to LINTEC Corporation. The applicant listed for this patent is LINTEC Corporation. Invention is credited to Tomonori Shinoda, Yoji Wakayama.
Application Number | 20140141570 14/162944 |
Document ID | / |
Family ID | 44762654 |
Filed Date | 2014-05-22 |
United States Patent
Application |
20140141570 |
Kind Code |
A1 |
Shinoda; Tomonori ; et
al. |
May 22, 2014 |
RESIN FILM FORMING SHEET FOR CHIP, AND METHOD FOR MANUFACTURING
SEMICONDUCTOR CHIP
Abstract
A sheet for forming a resin film for a chip, with which a
semiconductor device is provided with a gettering function, is
obtained without performing special treatment to a semiconductor
wafer and the chip. The sheet has a release sheet, and a resin
film-forming layer, which is formed on the releasing face of the
release sheet, and the resin film-forming layer contains a binder
polymer component, a curing component, and a gettering agent.
Inventors: |
Shinoda; Tomonori; (Saitama,
JP) ; Wakayama; Yoji; (Saitama, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
LINTEC Corporation |
Tokyo |
|
JP |
|
|
Assignee: |
LINTEC Corporation
Tokyo
JP
|
Family ID: |
44762654 |
Appl. No.: |
14/162944 |
Filed: |
January 24, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
13638113 |
Sep 28, 2012 |
8674349 |
|
|
PCT/JP2011/057969 |
Mar 30, 2011 |
|
|
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14162944 |
|
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Current U.S.
Class: |
438/114 ;
428/413 |
Current CPC
Class: |
H01L 23/26 20130101;
H01L 2224/32145 20130101; Y10T 428/31511 20150401; H01L 23/293
20130101; H01L 2924/3512 20130101; C09J 2203/326 20130101; H01L
2224/32245 20130101; H01L 21/6836 20130101; H01L 21/568 20130101;
H01L 2221/68327 20130101; C09J 7/22 20180101; H01L 2221/6834
20130101; H01L 2924/00 20130101; H01L 21/78 20130101; H01L 23/295
20130101; H01L 23/3164 20130101; H01L 2924/01019 20130101; H01L
2924/01012 20130101; H01L 23/564 20130101; H01L 24/32 20130101 |
Class at
Publication: |
438/114 ;
428/413 |
International
Class: |
H01L 21/78 20060101
H01L021/78; H01L 23/29 20060101 H01L023/29 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 31, 2010 |
JP |
2010-083690 |
Claims
1. A resin film forming sheet for chip comprising: a release sheet
and a resin film forming layer formed on a releasing face of said
release sheet, and said resin film forming layer includes a binder
polymer component, a curable component and a gettering agent,
wherein the gettering agent comprises an organic chelate agent, and
wherein a blending amount of the gettering agent is 1 to 35 parts
by weight with respect to 100 parts by weight of an entire solid
potion comprising the resin film forming layer.
2. The resin film forming sheet for chip as set forth in claim 1
wherein a copper ion absorbing ability of the gettering agent as
defined below is 30% or more: introducing 1 g of the gettering
agent into 50 g of copper chloride aqueous solution having a copper
ion concentration of 3 ppm, then measuring the copper ion
concentration of said copper ion solution after being left for 24
hours under 2 atmospheric pressure at 121.degree. C. to obtain the
copper ion absorbing ability by, copper ion absorbing ability=(3
ppm-remaining copper ion concentration (ppm)).times.100/3 ppm.
3. The resin film forming sheet for chip as set forth in claim 1,
wherein said resin film forming layer further comprises a coloring
agent.
4. The resin film forming sheet for chip as set forth in claim 1,
wherein the resin film forming layer is a protection film for a
semiconductor wafer or chip.
5. A production method of a semiconductor chip, comprising
obtaining a semiconductor chip comprising a resin film on a back
side by adhering the resin film forming layer of the resin film
forming sheet for chip as set forth in claim 1 to the back side of
a semiconductor wafer formed with a circuit on a front surface.
6. The production method of the semiconductor chip as set forth in
claim 5 further comprising: removing the release sheet; curing the
resin film forming layer; and dicing the semiconductor wafer and
the resin film forming layer.
7. The production method of the semiconductor chip as set forth in
claim 5, wherein the semiconductor wafer has a fractured layer
caused by the back side grinding being reduced to the thickness of
50 nm or less.
8. The production method of the semiconductor chip as set forth in
claim 5, wherein the resin film comprises a protection film of the
semiconductor chip.
Description
[0001] This is continuation application of U.S. Ser. No. 13/638,113
filed in the U.S. Patent and Trademark Office on Sep. 28, 2012,
which is a U.S. national stage application of PCT/JP2011/057969
filed on Mar. 30, 2011 which claims priority of Japanese patent
document 2010-083690 filed on Mar. 31, 2010, the entireties of
which are incorporated herein by reference.
TECHNICAL FIELD
[0002] The present invention relates to a resin film forming sheet
for chip capable of forming the resin film having a gettering
effect efficiently on a back side of a semiconductor wafer, and
also capable of improving the production efficiency of the chip.
Particularly, the present invention relates to the resin film
forming sheet for chip used for the production of the semiconductor
chip mounted by the so called face down method. Also, the present
invention relates to a production method of the semiconductor chip
using above mentioned resin film forming sheet for chip.
BACKGROUND OF THE INVENTION
[0003] Recently, due to the demand of making the element compact,
the semiconductor chip is demanded to be thinner. The semiconductor
chip is ground to the predetermined thickness by the back side
grinding after the circuit is formed on the front surface.
Therefore, in order to make the element compact, the wafer must be
ground further thinner by the back side grinding. However, along
with the thickness of the wafer becomes thinner, the wafer strength
declines, and the wafer may break even by a small impact. As a
cause of the wafer break, "a fractured layer" is thought to be the
main cause which is the mixture of the grinding scars of the
grinder used during the back side grinding or an oxidized layer or
so.
[0004] The fractured layer is a minute roughness of the wafer
surface which has been ground, and it is under the condition that a
polycrystalline of silicon or a silicon which has been oxidized by
small amount of the oxygen, further the lattice defect are thought
to be included. Due to the stress caused by the roughness or the
compositional changes of the surface, a crack may occur even by a
small impact and cause the wafer break. Thus, after the back side
grinding is completed, in order to remove the fractured layer, it
has been generalized to carry out the chemical etching or plasma
etching or so to the back side. By removing the fractured layers,
the wafer strength is improved, and a good handling property is
maintained even for the wafer which has been ground extremely
thin.
[0005] However, by removing the fractured layer, the deterioration
of the contamination resistance property of the obtained wafer or
chip against metals is concerned.
[0006] The semiconductor wafer contacts with various members when
forming the circuit or during the back side grinding and the
mounting or so. At this time, a metal such as copper or so is
released from these other members, and the wafer may be
contaminated by the metals. The metal impurities accumulates in the
wafer, and it may be ionized under the heat applying condition such
as reflow or so and may move inside the wafer. Then, the metal
which has reached the circuit surface interfere the electrical
operation of the product and causes a malfunction. Also, metal ion
which has reached the circuit surface may generate a metal at the
circuit face (these may be called as migration). Particularly, when
the metal is generated on the semiconductor wafer surface in which
the wiring is very minute, the short circuit may happen on the
circuit, and the yield of the product may decline.
[0007] On the other hand, as described in the above, the fractured
layer is a minute roughness and it is under the condition that a
polycrystalline of silicon or silicon which has been oxidized by
small amount of the oxygen, and further the lattice defect are
thought to be included, thus due to these composition and the
unevenness of the structures, said metal impurities are easily
captured, thereby it is thought that the influence of the metal
impurities may be reduced. The function of such fractured layer is
also called as the gettering function.
[0008] As such, by removing the fractured layer after the back side
grinding of the wafer, the strength of the wafer may be improved
however the gettering function is interfered, and the product yield
declines. Thus, the techniques is proposed to provide a gettering
function by carrying out a various treatment to the semiconductor
wafer or chip after the removal of the fractured layer (Patent
Articles 1 and 2).
PRIOR ART
[0009] [Patent Article 1] Japanese Patent application Laid Open
Publication No. 2005-277116 [Patent Article 2] Japanese Patent
application Laid Open Publication No. 2007-242713
SUMMARY OF THE INVENTION
[0010] However, by carrying out the treatment to provide the
gettering function to the semiconductor wafer or chip as described
in the patent articles 1 and 2 results in the increase of the
production steps, and complicates process and the increases of the
cost.
[0011] The present invention has been achieved by reflecting the
above situation, and the object is to provide the gettering
function to the obtained semiconductor device without carrying out
the treatment to the semiconductor wafer or the chips which
increases the steps, and complicates the process.
[0012] The present inventors have found as a result of keen
examination to solve the above described objects, by providing the
gettering function to the resin film formed on the back side of the
semiconductor chip, the gettering site can be introduced into the
semiconductor device thereby the present invention was
achieved.
[0013] The present invention includes the following points.
[0014] (1) A resin film forming sheet for chip comprising a release
sheet and a resin film forming layer formed on a releasing face of
said release sheet, and said resin film forming layer includes a
binder polymer component (A), a curable component (B) and a
gettering agent (C).
[0015] (2) The resin film forming sheet for chip as set forth in
(1) wherein the gettering agent (C) is selected from a group
consisting of a heavy metal inactivator (C1), a organic chelate
agent (C2) and a copper ion capture metal compound (C3).
[0016] (3) The resin film forming sheet for chip as set forth in
(1) or (2) wherein a copper ion absorbing ability of the gettering
agent (C) as defined in below is 30% or more:
[0017] introducing 1 g of the gettering agent into 50 g of copper
chloride solution having a copper ion concentration of 3 ppm, then
measuring the copper ion concentration of said copper ion solution
after being left for 24 hours under 2 atmospheric pressure at
121.degree. C. to obtain the copper ion absorbing ability by,
copper ion absorbing ability=(3 ppm-remaining copper ion
concentration (ppm)).times.100/3 ppm.
[0018] (4) The resin film forming sheet for chip as set forth in
any one of (1) to (3), wherein said resin film forming layer
further includes a coloring agent (D).
[0019] (5) The resin film forming sheet for chip as set forth in
any one of (1) to (4), wherein 1 to 35 parts by weight of the
gettering agent (C) is included per 100 parts by weight of an
entire solid portion constituting the resin film forming layer.
[0020] (6) The resin film forming sheet for chip as set forth in
any one of (1) to (5), wherein the resin film forming layer is a
protection film for a semiconductor wafer or chip.
[0021] (7) A production method of a semiconductor chip
characterized by obtaining a semiconductor chip comprising a resin
film on a back side by adhering a resin film forming layer of the
resin film forming sheet for chip as set forth in any one of (1) to
(6) to the back side of a semiconductor wafer formed with a circuit
on a front surface.
[0022] (8) The production method of the semiconductor chip as set
forth in (7) including following steps (1) to (3), and the steps
(1) to (3) are carried out in an arbitrary order:
[0023] Step (1): releasing a resin film forming layer and a release
sheet
[0024] Step (2): curing the resin film forming layer
[0025] Step (3): dicing the semiconductor wafer and the resin film
forming layer.
[0026] (9) The production method of the semiconductor chip as set
forth in (7) or (8), wherein the semiconductor wafer is the wafer
having a fractured layer caused by the back side grinding being
reduced to the thickness of 50 nm or less.
[0027] (10) The production method of the semiconductor chip as set
forth in any one of (7) to (9), wherein the resin film is a
protection film of the semiconductor chip.
[0028] When forming the resin film on the back side of the
semiconductor chip, by using the resin film forming sheet for chip
according to the present invention, the gettering site can be
introduced into the obtained semiconductor device without carrying
out a special treatment to the semiconductor wafer or the chip.
DETAILED DESCRIPTION OF THE INVENTION
[0029] Hereinafter, the present invention will be further
specifically explained including the best mode for carrying out the
invention. The resin film forming sheet for chip according to the
present invention comprises a release sheet, a resin film forming
layer formed on a releasing face of the release sheet.
(The Resin Film Forming Layer)
[0030] The resin film forming layer includes a binder polymer
component (A), a curable component (B), and a gettering agent
(C).
(A) The Binder Polymer Component
[0031] The binder polymer component (A) is used to provide a
sufficient bonding property and a film forming property (a sheet
process property) to the resin film forming layer. As for the
binder polymer component (A), conventionally known acrylic polymer,
polyester resin, urethane resin, acrylic urethane resin, silicone
resin, rubber polymer or so can be used.
[0032] The weight average molecular weight (Mw) of the binder
polymer component (A) is preferably 10000 to 2000000, and more
preferably 100000 to 1500000. If the weight average molecular
weight of the binder polymer component (A) is too low, the
releasing force between the resin film forming layer and the
release sheet is increased, and it may cause a transfer failure of
the resin film forming layer. On the other hand, if it is too high,
the bonding property of the resin film forming layer declines and
the chip or so may not be transferred or the resin film or so may
be released from the chip or so after the transferring.
[0033] As for the binder polymer component (A), an acrylic polymer
is preferably used. The glass transition temperature (Tg) of the
acrylic polymer is preferably within the range of -60 to 50.degree.
C., more preferably -50 to 40.degree. C., and particularly
preferably -40 to 30.degree. C. If the glass transition temperature
of the acrylic polymer is too low, the releasing force between the
resin film forming layer and the release sheet becomes large, and
it may cause a transfer failure of the resin film forming layer. On
the other if it is too high, the bonding property of the resin film
forming property declines and the chip or so may not be transferred
or the resin film or so may be released from the chip or so after
the transferring.
[0034] As for a monomer constituting the above mentioned acrylic
polymer, (meth)acrylate monomer or the derivatives thereof may be
mentioned. For example, alkyl(meth)acrylate having 1 to 18 carbon
atoms of the alkyl group such as methyl (meth)acrylate, ethyl
(meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate,
2-ehylhexyl (meth)acrylate or so may be mentioned; (meth)acrylate
having cyclic structure such as cycloalkyl (meth)acrylate, benzyl
(meth)acrylate, isobornyl (meth)acrylate, dicyclopentanyl
(meth)acrylate, dicyclopentenyl (meth)acrylate,
dicyclopentenyloxyethyl (meth)acrylate, imide (meth)acrylate or so
may be mentioned; hydroxymethyl (meth)acrylate, 2-hydroxyethyl
(meth)acrylate, 2-hydroxypropyl (meth)acrylate or so which
comprises hydroxyl group may be mentioned; and other than that
glycidyl (meth)acrylate or so which comprises epoxy group may be
mentioned. Among these, the acrylic polymer obtained by
polymerizing the monomer having hydroxyl group is preferable as it
has good compatibility with the curable component (B) which will be
described in below. Also, the above mentioned acrylic polymer may
be copolymerized with acrylic acid, methacrylic acid, itaconic
acid, vinyl acetate, acrylonitrile, styrene or so.
(B) The Curable Component
[0035] As the curable component (B), the heat curable component and
the heat curing agent are used. As for the heat curing component,
for example epoxy resin is preferable.
[0036] As for the epoxy resin, conventionally known epoxy resin can
be used. As for the epoxy resin, specifically, epoxy resin having
two or more of functional group in the molecule such as
polyfunctional epoxy resin, biphenyl compound, a bisphenol A
diglycidyl ether or the hydrogenates thereof, orthocresol novolac
epoxy resin, dicyclopentadiene epoxy resin, biphenyl epoxy resin,
bisphenol A epoxy resin, bisphenol F epoxy resin, phenylene
structure epoxy resin or so may be mentioned. These may be used
alone or by mixing two or more thereof.
[0037] At the resin film forming layer, the heat curing component
is included preferably by 1 to 1500 parts by weight, and more
preferably 3 to 1200 parts by weight with respect to 100 parts by
weight of binder polymer component (A). If the content of the heat
curable component is less than 1 parts by weight, a sufficient
bonding property may not be obtained, and if the it exceeds 1500
parts by weight, then the releasing force between the resin film
forming layer and the release sheet becomes high; thereby the
transfer failure of the resin film forming layer may happen.
[0038] The heat curing agent functions as curing agent against the
heat curable component particularly of epoxy resin. As the
preferable heat curing agent, the compound having tow or more
functional group in one molecule capable of reacting with the epoxy
group may be mentioned. As for such functional group, phenolic
hydroxyl group, alcoholic hydroxyl group, amino group, carboxyl
group and acid anhydrides or so may be mentioned. Among these,
preferably phenolic hydroxyl group, amino group, and acid unhydride
or so may be mentioned; and further preferably phenolic hydroxyl
group and amino group may be mentioned. Further, preferably
phenolic hydroxyl group and amino group may be mentioned.
[0039] As for the specific examples of the phenolic curing agent,
polyfunctional phenol resin, biphenol, novolac phenol resin,
dicyclopentadiene phenol resin, XYLOK phenol resin, aralkyl phenol
resin or so may be mentioned. As for specific examples of amine
curing agent, DICY (dicyandiamide) may be mentioned. These may be
used alone or by mixing two or more thereof.
[0040] The content of the heat curing agent is preferably 0.1 to
500 parts by weight, and more preferably 1 to 200 parts by weight
with respect to 100 parts by weight of the heat curing component.
If the content of the heat curing agent is too little, the bonding
property may not be obtained due to the insufficient curing, on the
other hand if it is too much, then the moisture absorbing rate of
the resin film forming layer increases and lowers the reliability
of the semiconductor device.
(C) The Gettering Agent
[0041] The gettering agent (C) is not particularly limited as long
as it has a function to capture the metal ion such as copper ion or
so; however it is used by selecting at least one from a group
consisting preferably of a heavy metal inactivator (C1), an organic
chelate agent (C2) and a copper ion capture metal compound (C3). By
bending the gettering agent (C) into the resin film forming layer,
the gettering function is provided to the resin film forming layer,
and the gettering site is introduced in the semiconductor
device.
(C1) The Heavy Metal Inactivator
[0042] The heavy metal inactivator is an additive blended in a
small amount to various plastics in order to prevent the plastic
deterioration due to the metal such as catalyst residue or so. The
heavy metal inactivator is thought to prevent the plastic
deterioration by capturing the metal component and reducing the
effect thereof. As for such heavy metal inactivator, various
inactivator of an inorganic type or an organic type are known,
however the organic heavy metal inactivator is preferably used in
the present invention. The organic heavy metal inactivator has
superior dispersibility in the resin film forming layer.
[0043] As for such heavy metal inactivator, the compound having a
following structure in the part of the molecule is particularly
preferably used.
##STR00001##
[0044] In the above formula, R is a hydrocarbon structure which may
comprise hydrogen or hetero atom; and it is preferably a
hydrocarbon structure comprising nitrogen atom and/or oxygen
atom.
[0045] As the particularly preferable example of such heavy metal
inactivator, the following compound may be mentioned. [0046]
3-(N-salicyloyl)amino-1,2,4-triazol (CDA-1, made by ADEKA
Corporation, CAS No. 36411-52-6).
[0046] ##STR00002## [0047]
Decamethylenedicarboxydisalicyloylhydrazide (CDA-6, made by ADEKA
Corporation, CAS No. 63245-38-5).
##STR00003##
[0047] (C2) The Organic Chelate Agent
[0048] The organic chelate agent (C2) is not particularly limited;
however it comprises a polyvalent carboxylic acid as the functional
group, and the acid value thereof is preferably 100 to 600 mg/g,
and more preferably 260 to 330 mg/g. When the acid value of the
organic chelate agent (C2) is smaller than 100 mg/g, then the
gettering function of the object is insufficient; on the other hand
when it is larger than 600 mg/g, then it may interact with basic
heat curing agent.
[0049] Also, the mass decline strating temperature by a
differential scanning calorimetry (TG/DTA) of the organic chelate
agent (C2) is preferably 190.degree. C. or higher, and more
preferably 196.degree. C. or higher. If the weight deline starting
temperature of the differential scanning calorimetry (TG/DTA) of
the organic chelate agent (C2) is lower than 190.degree. C., IR
reflow resistance property of the semiconductor device may
decline.
(C3) The Copper Ion Capture Metal Compound
[0050] The copper ion capture metal compound (C3) has an effect to
capture the copper ion. For example, an oxide, a hydroxide, a
nitrate or a carbonate of antimony, bismuth, magnesium, aluminum or
so may be mentioned. These are preferable since the effect can be
obtained even by small amount. As the example thereof, preferably
antimony oxides, bismuth oxides, and the mixture thereof, and
hydrotalcite which is an magnesium aluminum oxide and the fired
product may be mentioned. Note that, Al in the hydrotalcite may be
substituted with Cr or Fe.
[0051] As the gettering agent (C), the above mentioned can be used
alone or by mixing two or more thereof. Also, the blending amount
of the gettering agent (C) is preferably 1 to 35 parts by weight,
more preferably 10 to 35 parts by weight, and particularly
preferably 20 to 30 parts by weight with respect to 100 parts by
weight of entire solid portion constituting the resin film forming
layer. In case the blending amount of the gettering agent (C) is
too little, the gettering function of the object becomes
insufficient, and in case it is too much, then the bonding property
may be interfered.
[0052] By blending such gettering agent (C) in the resin film of
the semiconductor chip, the gettering cite can be introduced into
the semiconductor device. Therefore, the metal impurities
accumulated in the wafer is captured, under the heat applying
condition such as the reflow or so, by the gettering agent (C) in
the resin film even when it has moved; thus the migration will not
happen on the circuit surface.
[0053] The gettering function of the gettering agent (C) can be
evaluated by the following described copper ion absorbind
ability.
[0054] That is, 1 g of the gettering agent is introduced into 50 g
of a copper chloride aqueous solution having copper ion
concentration of 3 ppm which is made by dissolving 0.805 g of
copper (II) chloride dihydrate made by KANTO CHEMICAL CO., INC. in
1 L of ultra pure water and further diluting into 100-fold; then
this aqueous solution was left for 24 hours under 2 atmospheric
pressure at 121.degree. C. and measured the copper ion
concentration (the remaining copper ion concentration) of said
copper ion solution. Then, the copper ion absorbing ability was
evaluated from the following formula using the initial copper ion
concentration (3 ppm) and the remaining copper ion concentration
(ppm).
The copper ion absorbing ability=(3 ppm-the remaining copper ion
concentration (ppm)).times.100/3 ppm
[0055] The copper ion absorbing ability shows the ratio of the
copper ion captured (absorbed or taken-up) by the gettering agent,
and as the copper ion absorbing ability is high, the gettering
function is thought to be high. The copper ion absorbing ability of
the gettering agent (C) used in the present invention is preferably
30% or more, more preferably 50% or more, and particularly 95% or
more.
[0056] Also, the gettering function can also be evaluated by the
absorbed amount of the copper ion absorbed per unit weight of the
gettering agent (hereinafter, it will be refered as "a copper ion
absorbing rate"). Specifically, the gettering agent is introduced
into the copper ion aqueous solution as described in the above, and
the copper ion absorbing rate is obtained from the following
formula.
The copper ion absorbing rate (%)=(3 ppm-the remaining copper ion
concentration (ppm)).times.the solution amount
(g).times.10.sup.-6.times.100/the sample weight (g)
[0057] The copper ion absorbing rate of the gettering agent (C)
used in the present invention is preferably 0.003% or more, more
preferably 0.01% ore more, and particularly preferably 0.013% or
more.
[0058] The gettering agent (C) generally has broader surface area
per weight as the particle diameter is small; thus it becomes easy
to capture the metal impurities and increases the gettering
function. Also, in general, as the particle diameter is small, the
formation of the thick resin layer becomes easy. Therefore, the
average particle diameter of the gettering agent (C) used in the
present invention is preferably within the range of 1 nm to 30
.mu.m, more preferably 5 nm to 10 .mu.m, and particularly
preferably 10 nm to 1 .mu.m.
[0059] In case the particle diameter is large at the raw material
level, it is pulverized by suitable method (ball mill, triple roll
method or so) before or at the mixing with other components.
[0060] Note that, the average diameter of the gettering agent (C)
is obtained from the arithmetic mean of 100 particles observed by
the scanning electron microscope (SEM). When the shape of the
particle was not sphere, the longest diameter was defined as the
diameter.
(D) The Coloring Agent
[0061] The coloring agent (D) can be blended into the resin film
forming layer. By blending the coloring agent, when the
semiconductor device is incorporated into the machines, the
malfunction of the semiconductor caused by the infrared ray or so
generated from the surrounding devices can be prevented. As for the
coloring agent, the pigments and dies of organic or inorganic type
are used. Among these, a black pigment is preferable from the point
of the blocking property of the electromagnetic wave or the
infrared ray. As for the black pigment, carbon black, iron oxide,
manganese dioxide, aniline black, and activated carbon or so may be
used, but it is not limited thereto. The carbon black is
particularly preferable from the point of improving the reliability
of the semiconductor device. The blending amount of the coloring
agent (D) is preferably 0.1 to 35 parts by weight, more preferably
0.5 to 25 parts by weight, and most preferably 1 to 15 parts by
weight with respect to 100 parts by weight of entire solid portion
constituting the resin film forming layer.
[0062] Other Components
[0063] The resin film forming layer can include below described
components in addition to the above mentioned binder polymer (A),
curable component (B), gettering agent (C) and coloring agent
(D).
(E) A Heat-Curing Catalyst
[0064] The heat-curing catalyst (E) is used for control the curing
speed of the resin film forming layer. The heat-curing catalyst (E)
is preferably used in case the epoxy resin and the heat curing
agent are used together in the curable component (B).
[0065] As for the preferable heat-curing catalyst, a tertiary amine
such as triethylene diamine, benzyldimethyl amine, triethanol
amine, dimethylamino ethanol, tris(dimethylaminomethyl) pheniol or
so, imidazol such as 2-methylimidazol, 2-phenylimidazol,
2-phenyl-4-methylimidazol, 2-phenyl-4,5-dihydroxymethylimidazol,
2-phenyl-4-methyl-5-hydroxymethylimidazol or so; organic phosphine
such as tributylphosphine, diphenylphosphine, triphenylphosine or
so; tetraphenylboron salt such as
tetraphenylphosphoniumtetraohenylborate,
triphenylphosphinetetraphenylborate or so may be mentioned. These
may be used alone or by mixing two or more thereof.
[0066] The heat-curing catalyst (E) is included preferably within
the range of preferably 0.01 to 10 parts by weight, more preferably
0.1 to 1 parts by weight, with respect to 100 parts by weight of
curable component (B). By comprising the heat-curing catalyst in
the amount described in above range, it has superior bonding
characteristic even if it is exposed under the high temperature
high humidified condition, and also even if it is exposed to a
harsh reflow condition, a high reliability can be still attained.
If the content of the heat-curing catalyst (E) is too little, a
sufficient bonding property may not be obtained due to the
insufficient curing, and if it is too much, then the heat-curing
catalyst having high polarity moves to the bonding boundary side in
the resin film forming layer under a high temperature high
humidified condition, and the reliability of the semiconductor
device declines due to the segregation.
(F) The Coupling Agent
[0067] The coupling agent (F) is used for improving the bonding
property and the adhesive property against the chip of the resin
film forming layer. Also, by using the coupling agent (F), the
water resistance can be improved without interfering the heat
resistance of the resin film obtained by curing the resin film
forming layer.
[0068] As for the coupling agent (F), the compound comprising the
group capable of reacting with the functional group comprised in
the binder polymer component (A), and curable component (B). As for
the coupling agent (F), silane coupling agent is preferable. As for
such coupling agent, .gamma.-glycidoxypropyltrimethoxy silane,
.gamma.-glycidoxypropylmethyldiethoxy silane,
.beta.-(3,4-epoxycyclohexyl)ethyltrimethoxy silane,
.gamma.-(methacryloxypropyl)trimethoxy silane,
.gamma.-aminopropyltrimethoxy silane,
N-6-(aminoehtyl)-.gamma.-aminopropyltrimethoxy silane,
N-6-(aminoethyl)-.gamma.-aminopropylmethyldiethoxy silane,
N-phenyl-.gamma.-aminopropyltrimethoxy silane,
.gamma.-ureidepropyltriethoxy silane,
.gamma.-melcaptopropyltrimethoxy silane,
.gamma.-melcaptopropylmethyldimethoxy silane,
bis(3-triethoxysilylpropyl)tetrasulphone, methyltrimethoxy silane,
methyltriethoxy silane, vinyltrimethoxy silane, vinyltriacetoxy
silane, imidazol silane or so may be mentioned. These may be used
alone or by mixing two or more thereof.
[0069] The coupling agent (F) is included preferably by ratio of
usually 0.1 to 20 parts by weight, preferably 0.2 to 10 parts by
weight, and more preferably 0.3 to 5 parts by weight with respect
to 100 parts by weight of the total of the binder polymer component
(A) and the curable component (B). If the content of the coupling
agent (F) is less than 0.1 parts by weight, there is a chance that
the above mentioned effect cannot be obtained, and if it exceeds 20
parts by weight, it may become a cause of generating the
outgas.
(G) An Inorganic Filler
[0070] By blending the inorganic filler (G) in the resin film
forming layer, it becomes possible to control the heat expansion
coefficient at after the curing, thus the heat expansion
coefficient of the resin film after the curing is optimized with
respect to the semiconductor chip; thereby the reliability of the
semiconductor device can be improved. Also, the moisture absorbing
rate of the resin film after the curing can be reduced as well.
[0071] As for the preferable inorganic filler, powders such as
silica, talc, calcium carbonate, titanium white, bengala, silicon
carbide, boron nitride or so, a beads of which these has been made
into spherical form, a single crystal fiber and glass fiber or so
may be mentioned. Among these, silica filler is preferable. The
above mentioned inorganic filler (G) may be used alone or by mixing
two or more thereof. The content of the inorganic filler (G) is
adjustable within the range of usually 1 to 80 parts by weight with
respect to 100 parts by weight of the sntire solid portion
constituting resin film forming layer.
(H) An Energy Ray Polymerizable Compound
[0072] In the resin film forming layer, the energy ray
polymerizable compound may be blended. The energy ray polymerizable
compound (H) includes an energy ray polymerizable group, and
polymerizes and cures upon receiving the irradiation of the energy
ray such as the ultra violet ray, the electron beam or so. As for
specific examples of such energy ray polymerizable compound (H), an
acrylate compound such as trimethylolpropanetriacrylate,
pentaerythritoltriacrylate, pentaerythritoltetraacrylate, dip
entaerythrito lmonohydroxyp entaacrylate,
dipentaerythritolhexaacrylate or 1,4-butyleneglycoldiacrylate,
1,6-hexanedioldiacrylate, polyethyleneglycoldiacrylate,
oligoesteracrylate, urethaneacrylate oligomer, epoxy modified
acrylate, polyetheracrylate and itaconic acid oligomer or so may be
mentioned. Such compounds comprise at least one polymerizable
double bond in the molecule, and usually the weight average
molecular weight is 100 to 30000, preferably 300 to 10000 or so.
The blending amount of the energy ray polymerizable compound (H) is
not particularly limited, however it is preferably used in the
ratio of 1 to 50 parts by weight or so with respect to 100 parts by
weight of entire solid portion constituting the resin film forming
layer.
(I) A Photo-Polymerization Initiator
[0073] In case the resin film forming layer comprises the above
mentioned energy ray polymerizable compound (H), upon using, the
energy ray such as ultra violet ray or so is irradiated to cure the
energy ray polymerizable compound. At this time, by comprising the
photo-polymerization initiator (I) in said composition, the time
for polymerizing and curing, and also the photo irradiation amount
can be reduced.
[0074] As specific examples of such photo-polymerization initiator
(I), benzophenone, acetophenone, benzoin, benzoinmethylether,
benzoinethylether, benzoinisopropylether, benoinisobutylether,
bennzoin benzoic acid, benzoin methyl benzoic acid,
benzoindimethylketal, 2,4-diethylthioxanthone,
.alpha.-hydroxycyclohexylphenylketone, benzyldiphenylsulphide,
tetramethylthiurammonosulphide, azobisisobutyronitrile, benzil,
dibenzil, diacetyl, 1,2-diphenylmethane,
2-hydroxy-2-methyl-1-[4-(1-methylvinyl)phenyl]propanone,
2,4,6-trimethylbenzoyldiphenylphosphineoxide, and
.beta.-chloranthraquinone or so may be mentioned. The
photo-polymerization initiator (I) may be used alone or by
combining two or more thereof.
[0075] The blending amount of the photo-polymerization initiator
(I) is preferably 0.1 to 10 parts by weight, and more preferably 1
to 5 parts by weight with respect to 100 parts by weight of energy
ray polymerizable compound (H). If it is less than 0.1 parts by
weight, a sufficient transferring property may not be obtained due
to the insufficient photo-polymerization, and if it exceed 10 parts
by weight, the residues which do not contribute the
photo-polymerization remains and the curing property of the resin
film forming layer may be insufficient.
(J) a Thermoplastic Resin
[0076] The thermoplastic resin (J) may be included in the resin
film forming layer. The thermoplastic resin (J) is blended in order
to maintain the flexibility of the resin film after the curing. As
for the thermoplastic resin (J), those having weight average
molecular weight of 1000 to 100000 is preferable and more
preferably 3000 to 80000. By comprising the thermoplastic resin (J)
having the above range, the interlayer releasing between the
release sheet and the resin film forming layer can be carried out
easily during the transferring of the resin film forming layer to
the chip or the semiconductor wafer; and further the resin film
forming layer closely attaches at the transferring face and the
void or so can be suppressed.
[0077] The glass transition temperature of the thermoplastic resin
(J) is preferably -30 to 150.degree. C., and more preferably -20 to
120.degree. C. If the glass transition temperature of the
thermoplastic resin (J) is too low, the releasing force between the
resin film forming layer and the release sheet becomes too strong
and the transfer failure of the resin film forming layer may
happen; on the other hand, if it is too high, the bonding force
between the chip and the resin film forming layer may become
insufficient.
[0078] As for the thermoplastic resin (J), polyester resin,
urethane resin, phenoxy resin, polybutene, polybutadiene,
polystyrene or so may be mentioned. These may be used alone or by
mixing two or more thereof.
[0079] The thermoplastic resin (J) is included in the ratio of
usually 1 to 300 parts by weight, preferably 1 to 100 parts by
weight with respect to 100 parts by weight of the total of the
binder compound (A) and the curable component (B). When the content
of the thermoplastic resin (J) is within this range, the above
mentioned effects can be obtained.
(K) A Crosslinking Agent
[0080] The crosslinkling agent may be added in order to control the
initial bonding force and the adhesion of the resin film forming
layer. As for the crosslinking agent (K), organic polyvalent
isocyanate, organic polyvalent imine compound or so may be
mentioned.
[0081] As for the above mentioned organic polyvalent isocyanate,
aromatic polyvalent isocyanate compound, aliphatic polyvalent
isocyanate compound, alicyclic polyvalent isocyanate compound and
the trimer of the organic polyvalent isocyanate compound thereof,
and terminal isocyanateurethane pre-polymer obtained by reacting
these organic polyvalent isocyanate compounds and the polyol, may
be mentioned.
[0082] As for the organic polyvalent isocyanate compound for
example, 2,4-tolylenediisocyanate, 2,6-tolylenediisocyanate,
1,3-xylenediisocyanate, 1,4-xylenediisocyanate,
diphenylmethane-4,4'-diisocyanate,
diphenylmethane-2,4'-diisocyanate,
3-methyldiphenylmethanediisocyanate, hexamethylenediisocyanate,
isophoronediisocyanate, dicyclohexylmethane-4,4'-diisocyanate,
dicyclohexylmethane-2-4'-diisocyanate, trimethylolpropane adduct
tolylenediisocyanate, and lysine isocyanate or so may be
mentioned.
[0083] As for the above mentioned organic polyvalent imine
compounds, N--N'-diphenylmethane-4,4'-bis(1-aziridinecarboxyamide),
trimethylolpopane-tri-.beta.-aziridinylpropionate,
tetramethylolmethane-tri-.beta.-aziridinylpropionate, and
N,N'-toluene-2,4-bis(1-aziridinecarboxyamide)triethylenemelamine or
so may be mentioned.
[0084] The crosslinking agent (K) is used in the ratio of usually
0.01 to 20 parts by weight, preferably 0.1 to 10 parts by weight,
and more preferably 0.5 to 5 parts by weight with respect to 100
parts by weight of the binder polymer component (A).
(L) General-Purpose Additive Agents
[0085] Various additives may be blended depending on the needs into
the resin film forming layer besides the above described. As for
the various additives, a plasticizer, an antistatic agent, an
antioxidizer or so may be mentioned.
[0086] The resin film forming layer formed from each component as
described in the above has the bonding property and the heat
curable property, and at the non-cured condition, it is easily
bonded to the semiconductor wafer or chip or so by pressing. By
going through the heat curing, at the end, a resin film having high
impact resistance can be provided, and having superior bonding
strength, further sufficient protection function can be maintained
even under the harsh high temperature and high humidified
condition.
[0087] Note that, the resin film forming layer can be a single
layer structure, or it may be multilayer structure only if one or
more layer having above mentioned component is included. Further,
the resin film forming layer may have concentration gradient of the
gettering agent (C) with respect to the thickness direction.
(the Resin Film Forming Sheet for Chip)
[0088] The resin film forming layer is obtained by coating and
drying the resin film forming composition, on the release sheet,
formed by mixing in a suitable solution comprising the above
mentioned components in a suitable ratio. Also, the resin film
forming composition may be coated on the carrier film different
from the release sheet, then drying to form the resin film and it
may be transferred to the release sheet.
[0089] The resin film forming sheet for chip according to the
present invention is made by forming the above mentioned resin film
forming layer on the release sheet in a releasable manner. The
shape of the resin film forming sheet for chip according to the
present invention can be various shapes such as tape shape, a label
shape or so.
[0090] As for the release sheet, a transparent film may be used
such as, polyethylene film, polypropyrene, film, polybutene film,
polybutadiene film, polymehtylpentene film, polyvinyl chloride
film, vinyl chloride copolymer film, polyethylene telephthalate
film, polyethylene naphthalate film, polybutylenetelephthalate
film, polyurethane film, ethylene vinyl acetate copolymer film,
ionomer resin film, ethylene(meth)acrylic acid copolymer film,
ethylene(meth)acrylate copolymer film, polystyrene film,
polycarbonate film, polyimide film, fluorine resin film or so.
Also, the crosslinked film thereof may be used as well. Further, it
may be a laminated film thereof. Also, a colored film thereof,
non-transparent film or so can be used as well.
[0091] In the resin film forming sheet for chip of the present
invention, the release sheet is released upon using, and the resin
film forming layer is transferred to the semiconductor wafer or the
chip. Particularly, when releasing the release sheet after the heat
curing of the resin film forming layer, as the release sheet needs
to withstand the heat applying at the heat curing of the resin film
forming layer, polyethylenetelephthalate film, polyethylene
naphthalate film, polymethylpentene film, polyimide film or so
which has superior heat resistance are preferably used. In order to
make the releasing between the resin film forming layer and the
release sheet easier, the surface tension of the release sheet is
preferably 40 mN/m or less, more preferably 37 mN/m or less, and
particularly preferably 35 mN/m or less. The lower limit is usually
25 mN/m or so. The substrate having such low surface tension can be
obtained by selecting the suitably material, and also it can be
obtained by carrying out the releasing treatment by coating the
releasing agent on the surface of the substrate.
[0092] As for the releasing agent used for the releasing treatment,
the releasing agent of alkyd type, silicone type, fluorine type,
unsaturated polyester type, polyolefin type, wax type can be used;
however the releasing agent of alkyd type, silicone type and
fluorine type is preferably used as it has heat resistance.
[0093] In order to carry out the releasing treatment to the surface
of the sheet using the above mentioned releasing agent, the
releasing agent is used without the solvent, or by diluting in the
solvent or by emulsifying, and coating by gravure coater, Meyer bar
coater, air knife coater, or roll coater or so, then curing at room
temperature, by applying the heat or by electron beam, further the
laminated body can be formed by wet lamination or dried lamination,
thermofusion lamination, melt extrusion lamination, coextrusion
processing or so.
[0094] The thickness of the release sheet is usually 10 to 500
.mu.m, preferably 15 to 300 .mu.m, and particularly preferably 20
to 250 .mu.m or so. Also, the thickness of the resin film forming
layer is usually 1 to 500 .mu.m, preferably 5 to 300 .mu.m, and
particularly preferably 10 to 150 .mu.m or so.
[0095] Note that, before using the resin film forming sheet for
chip, in order to protect the resin film forming layer, on the top
face of the resin film forming layer, the releasing film which has
easy releasing property may be laminated separately than said
release sheet.
(the Production Method of the Semiconductor Chip)
[0096] The method of use of the resin film forming sheet for chip
according to the present invention will be explained taking the
case in which the sheet is applied in the production of the
semiconductor chip.
[0097] The production method of the semiconductor chip according to
the present invention is characterized by obtaining the
semiconductor chip having the resin film on the back side by
adhering the resin film forming layer of the above mentioned resin
film forming sheet for chip on the back side of the semiconductor
wafer of which the circuit is formed on the front surface. Said
resin film is preferably the protection film of the semiconductor
chip. Also, the production method of the semiconductor chip
according to the present invention preferably includes the
following steps of (1) to (3), and the steps (1) to (3) are carried
out in arbitrary order.
[0098] Step (1): Releasing the resin film forming layer and the
release sheet
[0099] Step (2): Curing the resin film forming layer
[0100] Step (3): Dicing the semiconductor wafer and the resin film
forming layer.
[0101] The semiconductor wafer may be silicon wafer, and it may be
a compound semiconductor wafer of gallium.arsenic or so. The
formation of the circuit to the wafer surface can be carried out by
various methods including a conventionally widely used method such
as etching method, liftoff method or so. Next, the opposite side
(back side) of the circuit face of the semiconductor wafer is
ground. The method of grinding is not particularly limited; and
known means using grinder or so may be used for the grinding. At
the back side grinding, in order to protect the circuit of the
front surface, the adhesive sheet so called surface protection
sheet is adhered to the circuit face. The back side grinding is
carried out by fixing the circuit face side of the wafer using the
chuck table or so, then the back side of which the circuit is not
formed is ground by grinder. The thickness after the wafer grinding
is not particularly limited, however usually it is 20 to 500 .mu.m
or so.
[0102] Then, depending on the needs, the fractured layer generated
during the back side grinding is removed. The fractured layer is
removed by a chemical etching, a plasma etching or so. By removing
the fractured layer, the gettering function that the wafer had will
decline; however by using the resin film forming layer of the
present invention, the gettering function is provided to the
obtained semiconductor device. Therefore, the production method of
the semiconductor chip of the present invention can be suitably
applied to the semiconductor wafer particularly to those which has
removed the fractured layer. That is, the production method of the
semiconductor chip of the present invention can be suitably applied
to the semiconductor wafer wherein the thickness of the fractured
layer is reduced to 50 nm or less, further to 30 nm or less,
particularly to 10 nm or less.
[0103] Next, on to the back side of the semiconductor wafer, the
resin film forming layer of the above mentioned resin film forming
sheet for chip is adhered. Then, the steps (1) to (3) are carried
out in arbitrary order. The detail of this process is described in
Japanese Patent Application Laid Open No. 2002-280329. As for one
example, the example of carrying out in the order of steps (1),
(2), (3) will be explained.
[0104] First, to the back side of the semiconductor wafer formed
with the circuit on the front surface, the resin film forming layer
of the resin film forming sheet for chip is adhered. Then, the
release sheet is removed from the resin film forming layer to
obtain the laminated body having semiconductor wafer and the resin
film forming layer. Next, the resin film forming layer is cured to
form the resin film on the entire face of the wafer. In the resin
film forming layer, the curable component (B) is included, thus
generally the resin film forming layer is cured by the heat curing.
Note that, in case the energy ray polymerizable compound (H) is
blended in the resin film forming layer, the curing of the resin
film forming layer can be carried out by both of the heat applying
or the energy ray irradiation; and the curing by the heat applying
and the energy ray irradiation may be carried out simultaneously or
sequentially. As a result, the resin film formed of the curable
resin is formed on the back side of the wafer, and the strength is
improved compared to the wafer alone; thereby the breakage during
the handling of the wafer made thinner can be reduced, and further
the gettering function is provided due to the gettering agent (C)
included in the resin film. Also, the evenness of the resin film is
superior compared to the coating method wherein the coating
solution for the resin film is directly coated to the back side of
the wafer or the chip to form the film.
[0105] Next, the laminated body of the semiconductor wafer and the
resin film is diced into each circuit formed on the wafer surface.
The dicing is carried out so that the wafer and the resin film are
both cut. The dicing of the wafer is carried out by usually method
of using the dicing sheet. As a result, the semiconductor chip
having the resin film on the back side is obtained.
[0106] Finally, by picking up the diced chip by usual method of
collet or so, the semiconductor chip having the resin film on the
back side is obtained. According to such the invention, the highly
even resin film can be easily formed on the back side of the chip,
and the cracks during the dicing step or after the packaging is
less likely to happen. Further, as the gettering function is
provided to the obtained semiconductor device, the migration is
reduced even in the reflow environment. Further, by mounting the
semiconductor chip on the predetermined substrate by a face-down
manner, the semiconductor device can be produced. Also, the
semiconductor device can be produced by bonding the semiconductor
chip having the resin film on the back side to other members (on
the chip mounting member) such as die pad portion or other
semiconductor chip or so.
Example
[0107] Hereinafter, the present invention will be described by
referring to the examples; however the present invention is not to
be limited thereto. Note that, in the examples and the comparative
examples described in below, <the copper ion absorbing ability
and the copper ion absorbing rate>, <the gettering function
evaluation>, and <the weight decline starting temperature
measurement> were carried out as described in the following.
<The Copper Ion Absorbing Ability and the Copper Ion Absorbing
Rate>
[0108] 1 g of the gettering agent prepared in the examples and the
comparative examples were introduced in 50 g of the copper chloride
aqueous solution having a copper ion concentration of 3 ppm which
was prepared by dissolving 0.805 g of copper (II) chloride
dihydrate made by KANTO CHEMICAL CO., INC. in 1 L of ultra pure
water and further diluting into 100-fold solution; then it was left
for 24 hours under 2 atmospheric pressure at 121.degree. C. Then,
it was filtered using a membrane filter having pore diameter of
0.10 .mu.m. The remaining copper ion concentration of the copper
ion solution of the filtrate was measured by atomic absorption
spectrophotometry (measuring device: Atomic Absorption
Spectrophotometer Z5310, flame method, made by Hitachi, Ltd), and
the copper ion absorption ability and the copper ion absorbing rate
were evaluated from the following formula using the initial ion
concentration (3 ppm) and the remaining copper ion concentration
(ppm).
The copper ion absorbing ability (%)=(3 ppm-the remaining copper
ion concentration (ppm)).times.100/3 ppm
The copper ion absorbing rate (%)=(3 ppm-the remaining copper ion
concentration (ppm)).times.solution amount
(g).times.10.sup.-6.times.100/the sample weight (g)
<The Gettering Function Evaluation>
[0109] Using DGP8760 made by DISCO Corporation, the back side of
the silicon wafer was carried out with the dry polish treatment
(200 mm diameter, the thickness 75 .mu.m, the fracture thickness 10
nm). To the face of the silicon wafer (the back side of the wafer)
carried out with the dry polish treatment, 1 g of copper (II)
chloride powder (made by KANTO CHEMICAL CO., INC., product name:
copper (II) chloride dihydride) was evenly sprayed, and introduced
into the pseudo-reflow condition (300.degree. C., 30 minutes);
thereby the copper ion was diffused in the silicon wafer. Then, the
low adhesion tape (the post cured Adwill D-675 made by Lintec
Corporation) was repeatedly adhered and released to remove the
copper (II) chloride powder from the wafer back side.
[0110] Then, on to this silicon wafer back side contaminated with
the copper ion, the resin film forming sheet for chip prepared in
the examples and the comparative examples were adhered at
40.degree. C. 30 minutes later, the ultra violet ray was irradiated
(230 mW/cm.sup.2, 120 mJ/cm.sup.2) from the releasing film face
using the ultraviolet ray irradiating device (Adwill RAD-2000 m/12
made by Lintec Corporation) to release the release sheet. Then, it
was heat cured (140.degree. C., 1 hour), and introduced under the
pseudo-reflow condition (300.degree. C., 30 min).
[0111] The wafer surface (the mirror face, the face without the
resin film forming sheet for chip) was washed by hydrofluoric acid
in advance to remove the contamination attached to the surface and
the oxide layer (about 10 nm) naturally formed on the surface.
Then, 10 mm of the wafer outer circumference was held by being
sandwiched with the Teflon (registered Trademark) jigs so that the
wafer outer circumference is masked by the Teflon; and 5 .mu.m from
the wafer surface was etched by nitric acid/hydrofluoric acid mixed
solution (the ratio 3:1). The whole amount of the solution used for
the etching was collected to the evaporating dish. After the
collected etching solution is heated.evaporated and exsiccation,
the residue was dissolved in the predetermined mixed solution of
the nitric acid/the hydrofluoric acid; thereby this was defined as
the copper ion concentration measurement samples. Note that, the
preparation of the samples was carried out in the clean draft
(class 10) provided in the clean room (class 100).
[0112] The concentration of the copper ion in the silicon wafer was
quantified by ICP-MS measurement.
[0113] Device: ELAN6100DRC Plus made by ParkinElmer Inc.
[0114] Condition: Plasma power of 1500 W. The lower limit of the
copper ion quantification is 3.0.times.10.sup.12 atoms/cm.sup.3
(the number of atoms per unit volume).
[0115] By measuring the copper ion concentration eluted from the
etching solution, the gettering function of the resin film forming
sheet for chip was evaluated. As the copper ion eluted out to the
etching solution is less, more copper ion is captured by the resin
film, and indicates the high gettering function. When the copper
ion detection amount is 50.times.10.sup.12 atoms/cm.sup.3 or less
it is considered good, and those exceeding 50.times.10.sup.12
atoms/cm.sup.3 was considered bad.
[0116] Note that, the quantification analysis method of the copper
ion concentration may be carried out by the methods such as the
atomic absorption spectrophotometry, ICP-OES, TOF-SIMS or so.
<The Mass Decline Starting Temperature Measurement>
[0117] The measurement of the mass decline starting temperature is
carried out by using the differential thermal analyzer (TG/DTA
analyzer DTG-60 made by Shimadzu Corporation). The organic chelate
agent prepared in the examples and the comparative examples were
used as the measuring samples, and about 10 mg of measuring sample
was accurately scaled. The temperature of the measuring sample was
raised to 40 to 500.degree. C. at the temperature rising speed of
10.degree. C./min, and the weight decline starting temperature was
measured.
<The Resin Film Forming Layer Composition>
[0118] Each component constituting the resin film forming layer is
shown in below.
(A) The binder polymer component: acrylic polymer (the weight
average molecular weight: 900000, the glass transition temperature
-28.degree. C.) comprising 55 parts by weight of n-butylacrylate,
15 parts by weight of methyl acrylate, 20 parts by weight of
glycidyl methacrylate, 15 parts by weight of
2-hydroxyethylacrylate
(B) The Curable Component:
[0119] (B1) bisphenol A epoxy resin (epoxy equivalent of 180 to 200
g/eq) (B2) dicyclopentadiene epoxy resin (EPICLON HP-7200HH made by
DIC Corporation) (B3) Heat curing agent: dicyandiamide (ADEKA
hardener 3636AS made bay ADEKA CORPORATION).
(C) The Gettering Agent
[0120] (C1-1) 3-(N-salicyloyl)amino-1,2,4-triazol (CDA-1, made by
ADEKA CORPORATION, CAS No. 36411-52-6) (The copper ion absorbing
ability 99.7%, the copper ion absorbing rate 0.015%, the particle
diameter 1 .mu.m)
##STR00004##
(C1-2) decamethylenedicarboxydisalicyloylhydrazide (CDA-6, made by
ADEKA CORPORATION, CAS No. 63245-38-5) (the copper ion absorbing
ability 95%, the copper ion absorbing rate 0.014%, the particle
diameter 0.5 .mu.m)
##STR00005##
(C2) The organic chelate agent: the organic chelate agent
comprising polyvalent carboxylic acid as the functional group
(Tekuran Do, the acid value 260 to 330 mg/g, the weight decline
strating temperature 200.degree. C., made by Nagase ChemteX
Corporation) (The copper ion absorbing ability 95.7%, the copper
ion absorbing rate 0.014%, the particle diameter 1 .mu.m) (C3)
KW-2200 made by Kyowa Chemical Industry Co., Ltd (hydrotalcite
comprising the oxide of magnesium and aluminum) (the copper ion
absorbing ability 99.8%, the copper ion absorbing rate 0.015%, the
particle diameter of 1 .mu.m) (D) The coloring agent: Black pigment
(carbon black, made by Mitsubishi Chemical Corporation, #MA650, the
average diameter of 28 nm) (E) The heat-curing catalyst: Imidazol
(Curezol 2PHZ made by CHIKOKU CHEMICAL CORPORATION) (F) The
coupling agent: A-1110 (made by Nippon Unicar Company Limited) (G)
The inorganic filler: silica filler (molten silica filler, the
average particle diameter 8 .mu.m)
The Examples and the Comparative Examples
[0121] The above mentioned each component was blended in an amount
shown in Table 1 to obtain the resin film forming layer
composition. The methyl ethyl ketone solution (the solid
concentration 61 wt %) of the obtained composition was coated on
the releasing treated face of the release sheet (SP-PET3811 made by
Lintec Corporation, the thickness 38 .mu.m, the surface tension
force 33 mN/m, the melting point 200.degree. C. or higher) carried
out with the releasing treatment with silicone so that the
thickness after drying becomes 40 .mu.m, then dried (the drying
condition: 100.degree. C. for 3 minutes in the oven); thereby the
resin film forming layer is formed on the release sheet and
obtained the resin film forming sheet for chip.
TABLE-US-00001 TABLE 1 Example 1 Example 2 Example 3 Example 4
Example 5 Example 6 Example 7 Comparative example 1 A 100 100 100
100 100 100 100 100 B1 50 50 50 50 50 50 50 50 B2 50 50 50 50 50 50
50 50 B3 2.8 2.8 2.8 2.8 2.8 2.8 2.8 2.8 C C1-1:57.1 C1-2:57.1
C2:57.1 C3:57.1 C3:5.2 C3:129.0 C3:157.1 D 10 10 10 10 10 10 10 10
E 2.8 2.8 2.8 2.8 2.8 2.8 2.8 2.8 F 1 1 1 1 1 1 1 1 G 300 300 300
300 300 300 150 300 Unit: parts by weight (in terms of solid
portion)
[0122] By using the obtained resin film forming sheet for chip,
<the copper ion absorbing ability and the copper ion absorbing
rate> and <the gettering function evaluation> were carried
out. The result and the content of the gettering agent with respect
to 100 parts by weight of the above mentioned bonding agent
composition is shown in Table 2.
TABLE-US-00002 TABLE 2 The gettering agent (the blending amount
with respect The The to 100 parts by copper The gettering weight of
the ion copper function bonding agent absorbing ion
(.times.10.sup.12 composition) ability absorbing atoms/ (parts by
weight) (%) rate (%) cm.sup.3) Example 1 10 99.7 0.015 9.5 2 10 95
0.014 15.3 3 10 95.7 0.014 14.2 4 10 99.8 0.015 8.4 5 1 99.8 0.015
40.5 6 20 99.8 0.015 4.5 7 30 99.8 0.015 N.D. Comparative 1 none --
-- 80 example Reference 1 -- -- -- N.D. example 2 -- -- -- 80
[0123] Note that, the gettering function of the wafer without the
copper ion contamination (the reference example 1) and the wafer
without adhereing the resin film forming sheet but carried out with
the copper ion contamination (the reference example 2) were
measured.
[0124] The resin film forming sheet for chip of the examples
exhibited excellent copper ion absorbing ability, copper ion
absorbing rate, and the gettering function. From these results, it
was confirmed that by using the gettering agent (C) in the resin
film forming layer, the semiconductor chip with high reliability
can be obtained.
* * * * *