U.S. patent application number 14/790146 was filed with the patent office on 2015-10-22 for semiconductor apparatus, method of manufacturing semiconductor apparatus, and electronic apparatus.
The applicant listed for this patent is c/o SONY CORPORATION. Invention is credited to Hiroshi OZAKI, Satoru WAKIYAMA.
Application Number | 20150303167 14/790146 |
Document ID | / |
Family ID | 47712067 |
Filed Date | 2015-10-22 |
United States Patent
Application |
20150303167 |
Kind Code |
A1 |
WAKIYAMA; Satoru ; et
al. |
October 22, 2015 |
SEMICONDUCTOR APPARATUS, METHOD OF MANUFACTURING SEMICONDUCTOR
APPARATUS, AND ELECTRONIC APPARATUS
Abstract
A semiconductor apparatus, including: a semiconductor component;
a Cu stud bump that is formed on the semiconductor component; and a
solder bump configured to electrically connect to the Cu stud
bump.
Inventors: |
WAKIYAMA; Satoru; (Kanagawa,
JP) ; OZAKI; Hiroshi; (Kanagawa, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
c/o SONY CORPORATION |
TOKYO |
|
JP |
|
|
Family ID: |
47712067 |
Appl. No.: |
14/790146 |
Filed: |
July 2, 2015 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
13568574 |
Aug 7, 2012 |
9105625 |
|
|
14790146 |
|
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Current U.S.
Class: |
438/108 |
Current CPC
Class: |
H01L 2224/73204
20130101; H01L 2224/13147 20130101; H01L 2224/13655 20130101; H01L
2224/83862 20130101; H01L 2224/81815 20130101; H01L 2224/81815
20130101; H01L 2224/81951 20130101; H01L 2224/13147 20130101; H01L
27/14683 20130101; H01L 2224/81411 20130101; H01L 2224/81413
20130101; H01L 2224/83862 20130101; H01L 2224/11848 20130101; H01L
2224/73104 20130101; H01L 2224/27416 20130101; H01L 2924/00014
20130101; H01L 2224/81355 20130101; H01L 25/50 20130101; H01L
2224/16238 20130101; H01L 2224/11436 20130101; H01L 2224/81411
20130101; H01L 2924/15788 20130101; H01L 24/11 20130101; H01L 24/16
20130101; H01L 24/81 20130101; H01L 2224/11416 20130101; H01L
2224/16503 20130101; H01L 24/13 20130101; H01L 2224/1319 20130101;
H01L 2224/1134 20130101; H01L 2224/11825 20130101; H01L 2224/1319
20130101; H01L 2224/83104 20130101; H01L 2924/00014 20130101; H01L
2924/00 20130101; H01L 2924/00014 20130101; H01L 2924/00014
20130101; H01L 2924/01083 20130101; H01L 2924/00014 20130101; H01L
2224/05552 20130101; H01L 2924/00 20130101; H01L 2924/00014
20130101; H01L 2924/00014 20130101; H01L 2924/00014 20130101; H01L
2924/01049 20130101; H01L 2224/11 20130101; H01L 2924/00012
20130101; H01L 2924/00014 20130101; H01L 2924/00014 20130101; H01L
2924/00014 20130101; H01L 2924/01049 20130101; H01L 2924/00014
20130101; H01L 2924/00014 20130101; H01L 2924/00014 20130101; H01L
2924/00014 20130101; H01L 23/49816 20130101; H01L 2924/00014
20130101; H01L 2224/8102 20130101; H01L 2224/81413 20130101; H01L
2224/11436 20130101; H01L 27/14618 20130101; H01L 2224/13562
20130101; H01L 2224/16503 20130101; H01L 2225/06513 20130101; H01L
2224/83104 20130101; H01L 2224/83191 20130101; H01L 2224/27436
20130101; H01L 2224/13076 20130101; H01L 2224/1134 20130101; H01L
2224/1357 20130101; H01L 2924/01322 20130101; H01L 2224/81805
20130101; H01L 2924/01322 20130101; H01L 2924/01029 20130101; H01L
2224/05567 20130101; H01L 2924/15321 20130101; H01L 2924/00014
20130101; H01L 2924/15788 20130101; H01L 21/563 20130101; H01L
2224/2919 20130101; H01L 2224/13019 20130101; H01L 2224/94
20130101; H01L 2224/0401 20130101; H01L 2224/13655 20130101; H01L
2224/2919 20130101; H01L 2224/81411 20130101; H01L 2224/81193
20130101; H01L 2224/8181 20130101; H01L 2224/11416 20130101; H01L
2224/94 20130101 |
International
Class: |
H01L 23/00 20060101
H01L023/00; H01L 25/00 20060101 H01L025/00 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 17, 2011 |
JP |
2011-178390 |
Claims
1. A method of manufacturing a semiconductor apparatus, comprising:
forming a Cu stud bump on a semiconductor component; and flip-chip
connecting the Cu stud bump to a solder bump.
2. The method of manufacturing a semiconductor apparatus according
to claim 1, wherein heating is performed at 200.degree. C. or lower
in at least one of during the flip-chip connecting and after the
flip-chip connecting.
3. The method of manufacturing a semiconductor apparatus according
to claim 1 further comprising: forming a plating layer on a surface
of the Cu stud bump by an electroless plating method.
4. The method of manufacturing a semiconductor apparatus according
to claim 3, wherein the plating layer is formed directly on an
outer surface of the Cu stud bump.
5. The method of manufacturing a semiconductor apparatus according
to claim 4, wherein the plating layer is formed directly on an
outer surface of the Cu stud bump that is not brought in contact
with the solder bump.
6. The method of manufacturing a semiconductor apparatus according
to claim 3, wherein the plating layer includes a Co plating layer
and includes one of a plating layer of Ni or Au.
7. The method of manufacturing a semiconductor apparatus according
to claim 1 further comprising: forming an alloy layer in between
and immediately adjacent to each of the Cu stud bump and the solder
bump such that the alloy layer is in contact with each of the Cu
stud bump and the solder bump.
8. The method of manufacturing a semiconductor apparatus according
to claim 1, wherein the solder bump for flip-chip connecting the Cu
stud bump is formed of at least one material selected from among
the group of In, SnBi, SnIn, and BiIn.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] The present application is a continuation of U.S. patent
application Ser. No. 13/568,574 filed on Aug. 7, 2012 which claims
priority from Japanese Patent Application No. JP 2011-178390 filed
in the Japanese Patent Office on Aug. 17, 2011, the entire content
of which is incorporated herein by reference.
BACKGROUND
[0002] The present disclosure relates to a semiconductor apparatus,
a method of manufacturing the semiconductor apparatus, and an
electronic apparatus that are configured to be connected using a
stud bump.
[0003] As a flip-chip connection technique of a semiconductor
apparatus, there is a method of connecting an Au stud bump to an
SnAg solder bump or a method of connecting an Au stud bump to an Sn
solder bump which is coated with Pd (Japanese Patent Application
Laid-Open Nos. 2009-218442 and 2009-239278).
[0004] There is a flip-chip connection technique for connecting an
Au stud bump to a Cu electrode of a semiconductor chip (Japanese
Patent Application Laid-Open No. 2001-60602) or a flip-chip
connection technique for connecting an Au stud bump to an Sn-plated
Cu electrode (Japanese Patent Application Laid-Open No.
2005-179099).
[0005] Moreover, a Cu stud bump substituted for an Au stud bump has
been suggested (Japanese Patent Application Laid-Open No.
2011-23568).
SUMMARY
[0006] In the flip-chip connection technique using the above
described stud bump, it has been demanded to improve connection
reliability of a semiconductor apparatus.
[0007] The present disclosure provides a semiconductor apparatus, a
method of manufacturing the semiconductor apparatus, and an
electronic apparatus which have high connection reliability.
[0008] The semiconductor apparatus in the present disclosure
includes a semiconductor component, a Cu stud bump formed on the
semiconductor component, and a solder bump electrically connected
to the Cu stud bump.
[0009] Moreover, the method of manufacturing the semiconductor
apparatus in the present disclosure includes forming the Cu stud
bump on the semiconductor component and flip-chip connecting the Cu
stud bump to the solder bump.
[0010] Moreover, the electronic apparatus in the present disclosure
includes the semiconductor apparatus and a signal processing
circuit configured to process an output signal of the semiconductor
apparatus.
[0011] According to the semiconductor apparatus and the method of
manufacturing the semiconductor apparatus, the flip-chip connection
is performed using the Cu stud bump, so that an alloy having a low
strength is not generated at a connection portion between Cu and a
solder even in low temperature connection. Therefore, connection
defects are prevented at the connection portion between the Cu stud
bump and the solder bump, and the connection reliability can be
improved.
[0012] According to the present disclosure, it is possible to
provide the semiconductor apparatus and the electronic apparatus
which have high connection reliability.
[0013] These and other objects, features and advantages of the
present disclosure will become more apparent in light of the
following detailed description of best mode embodiments thereof, as
illustrated in the accompanying drawings.
BRIEF DESCRIPTION OF DRAWINGS
[0014] FIG. 1A is a drawing showing a configuration of a stud bump
and a solder bump prior to flip-chip connection, and FIG. 1B is a
drawing showing a configuration of the stud bump and the solder
bump after the flip-chip connection;
[0015] FIG. 2A is another drawing showing a configuration of the
stud bump and the solder bump prior to the flip-chip connection,
and FIG. 2B is another drawing showing a configuration of the stud
bump and the solder bump after the flip-chip connection;
[0016] FIG. 3 is a cross-sectional view showing a configuration of
a semiconductor apparatus according to a first embodiment;
[0017] FIG. 4 is a drawing showing a configuration of a Cu stud
bump prior to the flip-chip connection;
[0018] FIG. 5 is a drawing showing a configuration of the Cu stud
bump and the solder bump after the flip-chip connection;
[0019] FIG. 6 is a drawing showing a process flow of the
semiconductor apparatus according to the first embodiment;
[0020] FIGS. 7A to 7C are manufacturing process diagrams of the Cu
stud bump;
[0021] FIGS. 8A to 8D are manufacturing process diagrams of the
solder bump;
[0022] FIGS. 9A to 9C are process diagrams of the flip-chip
connection by the Cu stud bump and the solder bump;
[0023] FIG. 10 is a drawing showing a modified example of the
process flow of the semiconductor apparatus according to the first
embodiment;
[0024] FIGS. 11A to 11C are process diagrams of the flip-chip
connection by the Cu stud bump and the solder bump;
[0025] FIG. 12 is a drawing showing a configuration of a modified
example of the semiconductor apparatus according to the first
embodiment;
[0026] FIG. 13 is a cross-sectional view showing a configuration of
a semiconductor apparatus according to a second embodiment;
[0027] FIG. 14 is a drawing showing a process flow of the
semiconductor apparatus according to a second embodiment;
[0028] FIG. 15 is a drawing showing a modified example of the
process flow of the semiconductor apparatus according to the second
embodiment; and
[0029] FIG. 16 is a drawing showing a configuration of an
electronic apparatus.
DETAILED DESCRIPTION OF EMBODIMENTS
[0030] Hereinafter, examples of embodiments for carrying out the
present disclosure will be described. However, the present
disclosure will not be limited to the following examples.
[0031] It is noted that the descriptions will be given below in
accordance with the following order.
1. Overview of semiconductor apparatus 2. First embodiment of
semiconductor apparatus 3. Method of manufacturing semiconductor
apparatus of First Embodiment 4. Second embodiment of semiconductor
apparatus 5. Method of manufacturing semiconductor apparatus of
Second Embodiment 6. Electronic apparatus
1. Overview of Semiconductor Apparatus
[0032] An overview of flip-chip connection of a semiconductor
apparatus will be described.
[0033] FIG. 1 show configurations of flip-chip connection using a
general Au stud bump of related art. FIG. 1A is a drawing showing a
configuration of an Au stud bump 11 and an Sn bump 12 prior to
connection. FIG. 1B is a drawing showing a configuration of the Au
stud bump 11 and the Sn bump 12 after the connection.
[0034] The Au stud bump 11 shown in FIG. 1A is the Au bump formed
of Au wires. The Au stud bump 11 is formed on an electrode 14 which
is formed on a semiconductor component 13. The semiconductor
component 13 is coated by a protective layer 15 except on the
electrode 14 on which the Au stud bump 11 is formed.
[0035] Moreover, the Sn bump 12 shown in FIG. 1A includes an Sn
group solder such as an SnAg solder bump. The Sn bump 12 includes
an electrode 17 formed on a wiring substrate 16 and an under bump
metal (UBM) 18 formed on the electrode 17. The wiring substrate 16
is coated by a protective layer 19 except on the electrode 17 on
which the UBM 18 is formed.
[0036] As shown in FIG. 1B, the semiconductor component 13 is
flip-chip connected on the wiring substrate 16 by the Au stud bump
11 and the Sn bump 12.
[0037] At this time, it may be necessary to connect the Au stud
bump 11 and the Sn bump 12 at 300.degree. C. or higher to improve
the connection reliability.
[0038] As shown in FIG. 1B, in the connection at 300.degree. C. or
lower, an intermetallic compound (IMC) 20 having a low strength
such as SnAu.sub.4 alloy is generated at a connection portion due
to diffusion of Au to Sn. Therefore, generation of a crack 24 and
the like may decrease in connectivity and reliability. Moreover,
since the Au stud bump 11 is stuck into the Sn bump 12, it is
difficult to prevent the diffusion of Au to Sn. Therefore, it is
difficult to prevent the generation of the IMC 20 at the connection
portion.
[0039] As described above, in the flip-chip connection performed by
the Au stud bump 11 and the Sn bump 12, it may be necessary to
perform high-temperature connection at 300.degree. C. or higher, so
that it is difficult to perform low-temperature connection in view
of the connection reliability.
[0040] Moreover, instead of using the Sn bump, as shown in FIG. 2,
it is considered that a low melting point solder bump of In group
is used to flip-chip connect the Au stud bump 11. FIG. 2A is a
drawing showing a configuration of an Au stud bump 21 and an In
bump 22 prior to connection. FIG. 2B is a drawing showing a
configuration of the Au stud bump 21 and the In bump 22 after the
connection.
[0041] The Au stud bump 21 shown in FIG. 2A has the same
configuration as FIG. 1A described above. Moreover, the In bump is
constituted of an In group solder. In this method, an alloy having
a low strength such as SnAu.sub.4 alloy is not generated, so that
it is possible to perform low-temperature flip-chip connection at
200.degree. C. or lower.
[0042] However, in the connection performed by using the Au stud
bump 21 and the In bump 22, a diffusion coefficient between Au and
In is large, so that it is difficult to control a growth of an AuIn
alloy. As a result, as shown in FIG. 2B, the In bump is sucked due
to a growth of an AuIn alloy 23. Therefore, in the flip-chip
connection performed by the Au stud bump 21 and the In bump 22, it
is difficult to secure the connectivity.
[0043] As described above, in the flip-chip connection using the
stud bump, it is difficult to perform low temperature processing in
view of the connection reliability. Therefore, in a case where a
material having a low heat resistance is mounted on the
semiconductor component and the like, it is difficult to apply the
flip-chip connection having high connection reliability. Therefore,
it has been demanded that a method of the flip-chip connection can
stably connect, at a low temperature, the semiconductor apparatus
and the like formed by using a material having a low heat
resistance and have high connection reliability.
2. First Embodiment of Semiconductor Apparatus
[Image Sensor: Configuration]
[0044] Hereinafter, a first embodiment of the semiconductor
apparatus will be described. FIG. 3 is a cross-sectional view
showing a configuration of the semiconductor apparatus according to
the first embodiment. In the first embodiment, the description will
be made taking an example of an image sensor as the semiconductor
apparatus. FIG. 3 is a cross-sectional view of a semiconductor
apparatus 30 formed of the image sensor mounted on a glass
substrate.
[0045] The semiconductor apparatus 30 is constituted of a
semiconductor component 31 including the image sensor, and a glass
substrate 32. The semiconductor component 31 includes an electrode
45 formed on the semiconductor component 31 and a Cu stud bump 41
formed on the electrode 45.
[0046] Moreover, the glass substrate 32 includes an electrode 47
for flip-chip connection formed on the glass substrate 32, the
under bump metal (UBM) 48 formed on the electrode 47, and a low
melting point solder bump 44 formed on the UBM 48. Further, a
wiring layer 34 formed on the glass substrate 32, a protective
layer 49 coating the wiring layer 34, an electrode 35 for external
connection connected to the wiring layer 34, and a solder ball 36
formed on the electrode 35 for external connection.
[0047] Moreover, an under-fill resin 33 which seals a connection
portion between the Cu stud bump 41 and the solder bump 44 is
provided between the semiconductor component 31 and the glass
substrate 32.
[0048] The semiconductor component 31 is an element generally used
as an image sensor and is a semiconductor element such as a CCD
(charge coupled device) image sensor and a CMOS (complementary
metal oxide semiconductor) image sensor. The semiconductor
component 31 is disposed so as to face a light receiving surface to
the glass substrate 32 side.
[0049] Moreover, the electrode 45 connected to the glass substrate
32 on the same surface as the light receiving surface is formed on
the semiconductor component 31. Then, the Cu stud bump 41 for
flip-chip connection is formed on the electrode 45. An alloy layer
43 is formed on a contact surface between the Cu stud bump 41 and
the solder bump 44. Moreover, the Cu stud bump 41 includes a
plating layer 42 on a surface which is not brought into contact
with the solder bump 44.
[0050] The glass substrate 32 is constituted of a cover glass used
for the image sensor, for example. Then, the electrode 47 for
flip-chip connection and the electrode 35 for external connection
are connected on the glass substrate 32 by the wiring layer 34. The
solder ball 36 for connection to external devices is formed on the
electrode 35. The solder ball 36 is used for a binary or ternary
solder of Sn group and the like. For example, SnBi, SnIn, SnAgCu,
SnZn, and SnAg and the like are used.
[0051] It is noted that the glass substrate 32 may be connected by
wire bonding using Au wires instead of the solder ball 36.
[Cu Stud Bump: Configuration]
[0052] Next, in the above described semiconductor apparatus 30,
FIG. 4 shows a configuration of the Cu stud bump 41 formed on the
semiconductor component 31. The Cu stud bump 41 shown in FIG. 4 is
a state prior to connection. Moreover, FIG. 5 shows a configuration
of the Cu stud bump 41 and the solder bump 44 after connecting the
semiconductor component 31 and the glass substrate 32.
[0053] As shown in FIG. 4, the Cu stud bump 41 is formed on the
electrode 45 on the semiconductor component 31. The semiconductor
component 31 is coated by a protective layer 46 except on the
electrode 45 on which the Cu stud bump 41 is formed.
[0054] Moreover, a surface of the Cu stud bump 41 is coated by the
plating layer 42.
[0055] The plating layer 42 is a protective layer for preventing
oxidation of the Cu stud bump 41. Moreover, when the Cu stud bump
41 is flip-chip connected, the plating layer 42 is formed of a
material which quickly diffuses the plating layer of the surface in
the solder bump 44.
[0056] As the plating layer 42, for example, a plating layer
constituted of a flash Ni plating layer and a flash Au plating
layer by an electroless method, or an electroless Co plating layer
is used.
[0057] Thicknesses of the plating layer 42 are formed at 0.01 to
0.1 .mu.m, for example.
[0058] Moreover, the solder bump 44 provided on the glass substrate
32 is formed of a low melting point solder. As the low melting
point solder, for example, a unary solder material of In, a low
melting point binary solder material such as Sn--Bi, Sn--In,
Bi--In, and a solder material formed by adding other metals to the
binary solder material are used. As the low melting point solder,
for example, a solder material whose melting point is 200.degree.
C. or lower is used.
[0059] Then, the Cu stud bump 41 formed on the semiconductor
component 31 is brought into pressing contact with the solder bump
44 of the glass substrate 32, thereby entering a top end of the Cu
stud bump 41 into the solder bump 44. Subsequently, heating is
performed in a state where the Cu stud bump 41 is stuck into the
solder bump 44, so that the flip-chip connection is performed as
shown in FIG. 5.
[0060] As shown in FIG. 5, when the flip-chip connection is
performed, the plating layer 42 of the contact surface between the
Cu stud bump 41 and the solder bump 44 is diffused into the solder
bump 44. Moreover, the alloy layer 43 of Cu and the solder is
formed on the contact surface between the Cu stud bump 41 and the
solder bump 44. At this time, it is suitable that the solder bump
44 is not entirely alloyed and the solder bump 44 which is not
alloyed is left on the UBM 48.
[0061] In the above-described configuration, it is possible to
prevent generation of alloy having a weak mechanical strength on an
interface of the low melting point solder bump 44 by using Cu as
the stud bump material of the flip-chip connection. Moreover, it is
possible to perform the flip-chip connection at a low temperature
by using the low melting point solder as the solder bump 44.
[0062] For example, in a case where the solder bump 44 is
constituted of In, an intermetallic compound of In.sub.3Cu.sub.7
and the like are formed on an interface between the Cu stud bump 41
and the solder bump 44. The intermetallic compound of
In.sub.3Cu.sub.7 has enough mechanical strength. Therefore, even in
the low-temperature flip-chip connection, an alloy having a low
strength which causes reduction in connection reliability is not
generated. Moreover, even in a combination of the Cu stud bump and
the low melting point binary solder material and the like, an alloy
layer having a weak mechanical strength is not generated on the
interface. Therefore, even in the semiconductor component 31 having
heat sensitive configuration, it is possible to apply the flip-chip
connection.
[0063] Therefore, in the flip-chip connection, it is possible to
perform low-temperature connection and further improve the
connection reliability of the semiconductor apparatus.
3. Method of Manufacturing Semiconductor Apparatus of First
Embodiment
[0064] A method of manufacturing the semiconductor apparatus of the
first embodiment will be described. It is noted that in the
following description, only the configuration in the vicinity of
the stud bump formed to the semiconductor apparatus will be
described. Other configurations can be manufactured by a well-known
method of related art.
[Manufacturing Method: Subsequent UF Resin Process Flow]
[0065] FIG. 6 shows a process flow of the semiconductor apparatus
30 shown in FIG. 3.
[0066] As shown in FIG. 6, elements such as photodiodes and various
kinds of transistors, and wirings and the like constituting the
semiconductor component 31 on a semiconductor base are formed by
the well-known method. At this time, the electrode 45 for external
connection is formed for performing flip-chip connection.
[0067] The Cu stud bump 41 is formed on the electrode 45 for
connecting to external devices of the semiconductor component
31.
[0068] The plating layer 42 is formed on the formed Cu stud bump 41
by an electroless plating method.
[0069] An opposite surface (rear surface) of a surface for forming
various kinds of elements on the semiconductor base is cut
(back-grinded: BG) and the semiconductor component 31 constituting
a rear-surface irradiation type solid-state imaging device is
formed.
[0070] The semiconductor base is subjected to dicing (DC) and the
semiconductor component 31 is separated into individual chips.
[0071] Moreover, the wiring layer 34, the electrode 47 and the like
are formed on the glass substrate 32 by the well-known method.
Then, the UBM 48 is formed on the electrode 47.
[0072] The solder bump 44 is formed on the UBM 48 using the low
melting point solder.
[0073] Next, the Cu stud bump 41 is brought into pressing contact
with (bonded to) the solder bump 44, thereby flip-chip connecting
the semiconductor component 31 which is separated into individual
chips to the glass substrate 32. After connection, the under-fill
(UF) resin 33 is injected around the connection portion between the
Cu stud bump 41 and the solder bump 44. Then, the injected UF resin
33 is heated and the UF resin is hardened (cured).
[0074] With the above process, the semiconductor apparatus 30 can
be manufactured.
[Manufacturing Method: Cu Stud Bump]
[0075] A Cu stud bump forming process in a process flow of the
above described semiconductor apparatus 30 will be described with
reference to a manufacturing process diagram shown in FIG. 7.
[0076] As shown in FIG. 7A, a Cu wire 51 is subjected to bonding on
the electrode 45 of the semiconductor component 31 using a
capillary 52. Then, as shown in FIG. 7B, the Cu stud bump 41 is
formed by cutting the Cu wire 51. In a formation process of the Cu
stud bump 41, for example, the Cu wire 51 having a diameter of 15
to 35 .mu.m.PHI. is used to form the Cu stud bump 41 having a
diameter of 30 to 70 .mu.m.PHI..
[0077] Next, as shown in FIG. 7C, the plating layer 42 is formed on
a surface of the formed Cu stud bump 41. The plating layer 42 is
formed by the electroless plating method. For example, a flash Ni
plating is performed on the surface of the Cu stud bump 41 by the
electroless plating method. Then, a flash Au plating is performed
on the flash Ni plating layer. Thus, the plating layer 42
constituting the Ni plating layer and the Au plating layer is
formed.
[0078] For example, in the plating layer 42, the Ni plating layer
and the Au plating layer are formed to have a thickness of 0.01 to
0.1 .mu.m, respectively.
[0079] Moreover, for example, Co plating is performed on the
surface of the Cu stud bump 41 as the plating layer 42 by the
electroless plating method. In this case, the plating layer 42
constituting the Co plating layer is formed to have a thickness of
0.01 to 0.1 .mu.m.
[0080] With the above process, the Cu stud bump 41 is formed on the
semiconductor component 31.
[Manufacturing Method: Solder Bump]
[0081] Next, a solder bump forming process in the process flow of
the semiconductor apparatus 30 will be described with reference to
a manufacturing process diagram shown in FIG. 8.
[0082] As shown in FIG. 8A, a barrier metal layer 53 is formed on a
surface of the electrode 47 and the protective layer 49.
[0083] Prior to forming the barrier metal layer 53, an oxide film
on the surface of the electrode 47 is removed through
reverse-sputtering. Subsequently, a Ti layer is formed on the
electrode 47 by a sputtering method. Then, a Cu layer is formed so
as to coat the Ti layer by the sputtering method. Thus, the barrier
metal layer 53 constituted of the Ti layer and the Cu layer is
formed.
[0084] Next, as shown in FIG. 8B, a resist layer 54 is formed on
the barrier metal layer 53. Then, the resist layer 54 is subjected
to exposure processing by a photo mask 55. In the photo mask 55, a
pattern for irradiating exposure light on a portion for forming the
electrode 47 is used.
[0085] Next, as shown in FIG. 8C, the under bump metal (UBM) 48 and
the solder bump 44 are formed in an opening formed by removing an
exposure portion of the resist layer 54 by an electro plating
method. The UBM 48 is formed by the electro plating method using
Ni, Ti, TiW, W, Cu, and the like. Moreover, the solder bump 44 is
formed by the electro plating method by use of a unary solder
material of In, a low melting point binary solder material such as
Sn--Bi, Sn--In, Bi--In, and the like.
[0086] Next, as shown in FIG. 8D, after the resist layer 54 is
removed, the barrier metal layer 53 exposed to the surface is
removed. Further, the solder bump 44 is melted into a spherical
form through a reflow.
[0087] With the above process, the solder bump 44 is formed on the
glass substrate 32.
[Manufacturing Method: Flip-Chip Connection]
[0088] Next, a flip-chip connecting process and a UF resin sealing
process in the process flow of the above described semiconductor
apparatus 30 will be described with reference to a manufacturing
process diagram shown in FIG. 9.
[0089] First, as shown in FIG. 9A, the semiconductor component 31
and the glass substrate 32 are aligned by facing a surface for
forming the Cu stud bump 41 and a surface for forming the solder
bump 44.
[0090] Next, as shown in FIG. 9B, while the Cu stud bump 41 and the
solder bump 44 are aligned, the semiconductor component 31 and the
glass substrate 32 are brought into pressing contact and are
flip-chip connected. At this time, pressing contact and heating are
simultaneously performed according to the flip-chip connection. The
plating layer 42 on the surface of the Cu stud bump 41 is diffused
into the solder bump 44 by thermal processing. Moreover, the alloy
layer 43 is generated and grown on a connection surface between the
Cu stud bump 41 and the solder bump 44 by thermal processing.
[0091] In the above described flip-chip connection, pressure
(bonding force) applied to each unit of bump during pressing
contact is 0.01 gf/bump to 10 gf/bump, for example. Moreover, a
heating temperature is set at 200.degree. C. or lower during the
flip-chip connection. Moreover, the heating temperature is set at a
temperature at or above a melting point of the solder bump 44 to be
used. For example, in a case where a solder of solid In is used for
the solder bump 44, the solder is heated at 156.degree. C. or
higher which is a melting point of In.
[0092] Next, as shown in FIG. 9C, the under-fill (UF) resin 33 is
applied to the connection portion between the Cu stud bump 41 and
the solder bump 44. Then, the UF resin 33 is heated and hardened.
In the UF resin 33, the semiconductor component 31 and the glass
substrate 32 are bonded, thereby improving mechanical connection
reliability of an adhesive surface of the semiconductor
apparatus.
[0093] With the above process, the semiconductor component 31 can
be flip-chip connected to the glass substrate 32.
[0094] In the above described flip-chip connection, it is possible
to perform a connection at 200.degree. C. or lower by using the low
melting point solder for the solder bump 44. Moreover, an alloy
having a low strength is not generated by using the Cu stud bump 41
even in the low-temperature flip-chip connection.
[0095] It is noted that in the above mentioned manufacturing
process, thermal processing for causing a growth of the alloy layer
does not need to be performed at the same time as the flip-chip
connection. For example, after the process for bringing into
pressing contact with and flip-chip connecting the semiconductor
component 31 and the glass substrate 32, annealing may be performed
in a different process. At this time, the annealing is performed at
200.degree. C. or lower.
Modified Example
Preliminary UF Resin Process Flow
[0096] Next, a modified example of a manufacturing method of the
above described semiconductor apparatus 30 will be described. In
the modified example, sealing flip-chip connection portion by the
UF resin is different from the above described manufacturing
method.
[0097] FIG. 10 shows a process flow which is changed in the UF
resin sealing process.
[0098] As shown in FIG. 10, elements such as photodiodes and
various kinds of transistors, and wirings and the like constituting
the semiconductor component 31 on the semiconductor base are formed
by the well-known method. At this time, the electrode 45 for
external connection is formed for performing flip-chip
connection.
[0099] The Cu stud bump 41 is formed on the electrode 45 for
connecting to external devices of the semiconductor component.
[0100] The plating layer 42 is formed on the formed Cu stud bump 41
by the electroless plating method.
[0101] The under-fill (UF) resin 33 is laminated on the formed Cu
stud bump 41.
[0102] An opposite surface (rear surface) of the surface for
forming various kinds of elements on the semiconductor base is cut
(back-grinded: BG) and the semiconductor component 31 constituting
a rear-surface irradiation type solid-state imaging device is
formed.
[0103] The semiconductor base is subjected to dicing (DC) and the
semiconductor component 31 is separated into individual chips.
[0104] Moreover, the wiring layer 34, the electrode 47 and the like
are formed on the glass substrate 32 by the well known method.
Then, the UBM 48 is formed on the electrode 47.
[0105] The solder bump 44 is formed on the UBM 48 using the low
melting point solder.
[0106] Next, the Cu stud bump 41 is brought into pressing contact
with (bonded to) the solder bump 44, thereby flip-chip connecting
the semiconductor component 31 which is separated into individual
chips to the glass substrate 32. After connection, the OF resin 33
is heated and is hardened (cured).
[0107] With the above process, the semiconductor apparatus 30 can
be manufactured.
[0108] Next, the UF resin forming process and the UF resin sealing
process in the process flow of the above described semiconductor
apparatus 30 will be described with reference to a manufacturing
process diagram shown in FIG. 11. It is noted that in the following
description, only the process which is different from the
manufacturing method of the above described semiconductor apparatus
will be described.
[0109] First, the plating layer 42 is formed on the Cu stud bump 41
by the above processes (FIG. 7C) and then the under-fill (UF) resin
33 covering the Cu stud bump 41 is formed as shown in FIG. 11A. The
under-fill (UF) resin 33 is formed by a spin coating method using a
coating liquid including the under-fill resin or a laminate of a
dry film of the under-fill resin, for example.
[0110] Next, as shown in FIG. 11B, the semiconductor component 31
and the glass substrate 32 are aligned by facing the surface for
forming the Cu stud bump 41 and the surface for forming the solder
bump 44. Then, as shown in FIG. 11C, the semiconductor component 31
and the glass substrate 32 are brought into pressing contact and
are flip-chip connected. Further, the alloy layer 43 is grown on
the connection surface between the Cu stud bump 41 and the solder
bump 44, and the UF resin 33 is hardened by thermal processing.
[0111] With the above process, the UF resin 33 covering the Cu stud
bump 41 is formed prior to the flip-chip connection and the
semiconductor apparatus 30 can be manufactured by a method of
hardening the UF resin 33 after the flip-chip connection.
[Modified Example of Semiconductor Apparatus]
[0112] In the semiconductor apparatus of the first embodiment, the
wiring substrate can be used instead of the glass substrate. FIG.
12 shows a configuration of the semiconductor apparatus which uses
the wiring substrate.
[0113] The semiconductor apparatus shown in FIG. 12 is constituted
of the semiconductor component 31 constituting the image sensor,
and a wiring substrate 37.
[0114] The semiconductor component 31 includes the electrode 45
formed on the semiconductor component 31 and the Cu stud bump 41
formed on the electrode 45.
[0115] Moreover, the wiring substrate 37 includes the electrode 47
for flip-chip connection formed on the wiring substrate 37, the
under bump metal (UBM) 48 formed on the electrode 47, and the low
melting point solder bump 44 formed on the UBM 48. Further, the
wiring substrate 37 includes the wiring layer 34 formed on the
glass substrate 32, the protective layer 49 coating the wiring
layer 34, the electrode 35 for external connection connected to the
wiring layer 34, and the solder ball 36 formed on the electrode 35
for external connection.
[0116] For example, the wiring substrate 37 includes a translucent
optical component 38 such as glass on the light receiving surface
of the semiconductor component 31. Then, the electrode 47, the UBM
48, and the solder bump 44 are formed on the wiring substrate 37
along a circumference of the optical component 38.
[0117] It is noted that the configurations of the semiconductor
component 31, the Cu stud bump 41 of the semiconductor component
31, and the like shown in FIG. 12 are the same as the first
embodiment. Moreover, the configurations of the solder bump 44, the
electrode 47, the wiring layer 34 and the like formed on the wiring
substrate 37 are the same as the first embodiment.
[0118] As the modified example described above, a component to
which the semiconductor component 31 including the Cu stud bump 41
is flip-chip connected is not particularly limited so long as an
electronic component including an electrode corresponding to the
flip-chip connection and the solder bump formed on the electrode is
employed. The electronic component to which the semiconductor
component is flip-chip connected may be the semiconductor element
and the like besides the glass substrate and the wiring substrate
which are described above, for example.
4. Second Embodiment of Semiconductor Apparatus
[0119] Next, a second embodiment of the semiconductor apparatus
will be described. FIG. 13 shows the semiconductor apparatus of the
second embodiment.
[0120] A semiconductor apparatus 60 shown in FIG. 13 includes a
first semiconductor component 61 and a second semiconductor
component 62. Then, the first semiconductor component 61 is mounted
on the second semiconductor component 62 by the flip-chip
connection.
[0121] The first semiconductor component 61 includes the electrode
45 formed on the first semiconductor component 61 and the Cu stud
bump 41 formed on the electrode 45. It is noted that the first
semiconductor component 61 is the same configuration as the
semiconductor component 31 of the first embodiment shown in FIG. 3
described above, so that the detailed description is omitted.
[0122] The second semiconductor component 62 includes the electrode
47 for flip-chip connection, the under bump metal (UBM) 48 formed
on the electrode 47, and the low melting point solder bump 44
formed on the UBM 48. Further, an end portion of the second
semiconductor component 62 includes a pad electrode 63 for wire
bonding for external connection. The semiconductor apparatus 60 is
electrically connected by wire bonding to an external electronic
apparatus by the pad electrode 63 for wire bonding of the second
semiconductor component 62. Moreover, the protective layer 49 is
provided on a surface of the second semiconductor component 62
except on the electrode 47 for flip-chip connection and the pad
electrode 63 for wire bonding.
[0123] The surface of the Cu stud bump 41 is coated by the plating
layer 42. As the plating layer 42, for example, the plating layer
constituted of the flash Ni plating layer and the flash Au plating
layer by the electroless method, or the electroless Co plating
layer is used.
[0124] The solder bump 44 is formed of a low melting point solder.
As the low melting point solder, the unary solder material of In,
the low melting point binary solder material such as Sn--Bi,
Sn--In, Bi--In, and the solder material formed by adding other
metals to the binary solder material are used.
[0125] The alloy layer 43 of Cu and the solder is formed on the
contact surface between the Cu stud bump 41 and the solder bump
44.
[0126] Moreover, in the semiconductor apparatus 60 shown in FIG.
13, the under-fill (UF) resin 33 which seals the entire connection
surface between the semiconductor components is provided between
the first semiconductor component 61 and the second semiconductor
component 62. The first semiconductor component 61 and the second
semiconductor component 62 are mechanically connected by the
under-fill (UF) resin 33. Then, the connection portion between the
Cu stud bump 41 and the solder bump 44 is formed into the
under-fill (UF) resin 33. Thus, in the semiconductor apparatus 60,
a fillet is formed by the under-fill resin 33 which fills between
the first semiconductor component 61 and the second semiconductor
component 62.
5. Method of Manufacturing Semiconductor Apparatus of Second
Embodiment
[First Manufacturing Method: Subsequent UF Resin Process Flow]
[0127] FIG. 14 shows a process flow of the semiconductor apparatus
60 shown in FIG. 13.
[0128] As shown in FIG. 14, elements such as various kinds of
transistors, and wirings and the like constituting the first
semiconductor component 61 on the semiconductor base are formed by
the well-known method. At this time, the electrode 45 for external
connection is formed for performing flip-chip connection.
[0129] The Cu stud bump 41 is formed on the electrode for
connecting to external devices of the first semiconductor component
61.
[0130] The plating layer 42 is formed on the formed Cu stud bump 41
by the electroless plating method.
[0131] The opposite surface (rear surface) of the surface for
forming various kinds of elements on the semiconductor base is cut
(back-grinded: BG). Then, the semiconductor base is subjected to
dicing (DC) and the first semiconductor component 61 is separated
into individual chips.
[0132] Moreover, elements such as various kinds of transistors, and
wirings and the like constituting the second semiconductor
component 62 on the semiconductor base are formed by the well-known
method. At this time, the electrode 47 for mounting the first
semiconductor component 61 is formed, and the UBM 48 is formed on
the electrode 47.
[0133] The solder bump 44 is formed on the UBM 48 using the low
melting point solder.
[0134] Then, the opposite surface (rear surface) of the surface for
forming various kinds of elements on the semiconductor base is cut
(back-grinded: BG). Then, the semiconductor base is subjected to
dicing (DC) and the second semiconductor component 62 is separated
into individual chips.
[0135] Next, the Cu stud bump 41 is brought into pressing contact
with (bonded to) the solder bump 44, thereby flip-chip connecting
the first semiconductor component 61 on the second semiconductor
component 62.
[0136] After flip-chip connection, the connection portion between
the Cu stud bump 41 and the solder bump 44 is covered and the
under-fill (UF) resin 33 is injected between the first
semiconductor component 61 and the second semiconductor component
62. Then, the injected UF resin 33 is heated and is hardened
(cured).
[0137] With the above process, the semiconductor apparatus 60 of
the second embodiment can be manufactured.
[0138] It is noted that formation of the Cu stud bump 41, formation
of the solder bump 44, and the flip-chip connection can be
performed by the same method as the first embodiment shown in FIGS.
7 to 9 described above.
[Second Manufacturing Method: Preliminary UF Resin Process
Flow]
[0139] Next, a modified example of a manufacturing method of the
semiconductor apparatus 60 of the second embodiment will be
described. In the modified example, sealing both of the
semiconductor components by the UF resin is different from the
above described manufacturing method.
[0140] FIG. 15 shows a process flow which is changed in the UF
resin sealing process.
[0141] As shown in FIG. 15, elements such as various kinds of
transistors, and wirings and the like constituting the first
semiconductor component 61 on the semiconductor base are formed by
the well-known method. At this time, the electrode 45 for external
connection is formed for performing flip-chip connection.
[0142] The Cu stud bump 41 is formed on the electrode for
connecting to external devices of the first semiconductor component
61.
[0143] The plating layer 42 is formed on the formed Cu stud bump 41
by the electroless plating method.
[0144] The formed Cu stud bump 41 is covered and the under-fill
(UF) resin 33 is laminated on the entire surface of the first
semiconductor component 61.
[0145] The opposite surface (rear surface) of the surface for
forming various kinds of elements on the semiconductor base is cut
(back-grinded: BG). Then, the semiconductor base is subjected to
dicing (DC) and the first semiconductor component 61 is separated
into individual chips.
[0146] Moreover, elements such as various kinds of transistors, and
wirings and the like constituting the second semiconductor
component 62 on the semiconductor base are formed by the well-known
method. At this time, the electrode 47 for mounting the first
semiconductor component 61 is formed, and the UBM 48 is formed on
the electrode 47.
[0147] The solder bump 44 is formed on the UBM 48 using the low
melting point solder.
[0148] Then, the opposite surface (rear surface) of the surface for
forming various kinds of elements on the semiconductor base is cut
(back-grinded: BG). Then, the semiconductor base is subjected to
dicing (DC) and the second semiconductor component 62 is separated
into individual chips.
[0149] Next, the Cu stud bump 41 is brought into pressing contact
with (bonded to) the solder bump 44, thereby flip-chip connecting
the first semiconductor component 61 on the second semiconductor
component 62. After connection, the injected UF resin is heated and
is hardened.
[0150] With the above process, the semiconductor apparatus 60 of
the second embodiment can be manufactured.
6. Electronic Apparatus
[Camera]
[0151] The semiconductor apparatus of the embodiments described
above may be applied to electronic apparatuses including a
semiconductor memory, a camera system such as a digital camera and
a video camera, a mobile phone having an imaging function, or other
devices having an image function, or the like. Hereinafter, the
description will be made taking a camera as a configuration example
of the electronic apparatus.
[0152] FIG. 16 shows a configuration example of the video camera
which is capable of taking a still image or a moving image.
[0153] A camera 70 of this example includes a solid-state imaging
device 71, an optical system 72 which guides incident light to a
light receiving sensor unit of the solid-state imaging device 71, a
shutter device 73 provided between the solid-state imaging device
71 and the optical system 72, and a driving circuit 74 which
drivers the solid-state imaging device 71. Further, the camera 70
includes a signal processing circuit 75 which processes an output
signal of the solid-state imaging device 71.
[0154] The solid-state imaging device 71 is fabricated using
semiconductor apparatus to which the solid-state imaging device
including the above described Cu stud bump is flip-chip
connected.
[0155] The optical system (optical lens) 72 focuses image light
(incident light) from a subject on an imaging surface (not shown)
of the solid-state imaging device 71. As a result, signal charges
are accumulated in the solid-state imaging device 71 for a
predetermined time period. It is noted that the optical-system 72
may be constituted of an optical lens group including a plurality
of optical lenses. Moreover, the shutter device 73 controls a light
irradiation period and a light blocking time period to the
solid-state imaging device 71 of the incident light.
[0156] The driving circuit 74 supplies a driving signal to the
solid-state imaging device 71 and the shutter device 73. Then, the
driving circuit 74 controls a signal output operation to the signal
processing circuit 75 of the solid-state imaging device 71 and a
shutter operation of the shutter device 73 by the supplied driving
signal. That is, in this example, based on the driving signal
(timing signal) supplied from the driving circuit 74, the signal
transmission operation is performed from the solid-state imaging
device 71 to the signal processing circuit 75.
[0157] The signal processing circuit 75 performs various kinds of
signal processing to the signal transmitted from the solid-state
imaging device 71. Then, the signal (image signal) subjected to the
various kinds of signal processing is stored in a storage medium
(not shown) such as memory or output to a monitor (not shown).
[0158] It is noted that the present disclosure can be configured as
follows.
[0159] (1) A semiconductor apparatus including: a semiconductor
component; a Cu stud bump that is formed on the semiconductor
component; and a solder bump configured to electrically connect to
the Cu stud bump.
[0160] (2) The semiconductor apparatus according to Item (1),
further including a plating layer that is formed on a surface of
the Cu stud bump.
[0161] (3) The semiconductor apparatus according to Item (1) or
(2), in which the solder bump contains at least one selected from
In, SnBi, SnIn, and BiIn.
[0162] (4) The semiconductor apparatus according to Item (2) or
(3), in which the plating layer includes one of a plating layer of
Ni and Au and a Co plating layer.
[0163] (5) A method of manufacturing a semiconductor apparatus,
including: forming a Cu stud bump on a semiconductor component; and
flip-chip connecting the Cu stud bump to a solder bump.
[0164] (6) The method of manufacturing a semiconductor apparatus
according to Item (5), further including forming a plating layer on
a surface of the Cu stud bump by an electroless plating method.
[0165] (7) The method of manufacturing a semiconductor apparatus
according to Item (5) or (6), in which heating is performed at
200.degree. C. or lower one of during the flip-chip connecting and
after the flip-chip connecting.
[0166] (8) An electronic apparatus, including: a semiconductor
apparatus described in any one of Items (1) to (4), and a signal
processing circuit configured to process an output signal of the
semiconductor apparatus.
[0167] The present disclosure contains subject matter related to
that disclosed in Japanese Priority Patent Application JP
2011-178390 filed in the Japan Patent Office on Aug. 17, 2011, the
entire content of which is hereby incorporated by reference.
[0168] It should be understood by those skilled in the art that
various modifications, combinations, sub-combinations and
alterations may occur depending on design requirements and other
factors insofar as they are within the scope of the appended claims
or the equivalents thereof.
* * * * *