U.S. patent application number 16/536971 was filed with the patent office on 2019-11-28 for stacked image sensor package.
This patent application is currently assigned to SEMICONDUCTOR COMPONENTS INDUSTRIES, LLC. The applicant listed for this patent is SEMICONDUCTOR COMPONENTS INDUSTRIES, LLC. Invention is credited to Weng-Jin WU.
Application Number | 20190363122 16/536971 |
Document ID | / |
Family ID | 67909164 |
Filed Date | 2019-11-28 |
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United States Patent
Application |
20190363122 |
Kind Code |
A1 |
WU; Weng-Jin |
November 28, 2019 |
STACKED IMAGE SENSOR PACKAGE
Abstract
Implementations of semiconductor packages may include: an image
sensor; an optically transmissive transparent coating directly
coupled to the image sensor; and a glass lid coupled directly
coupled to the optically transmissive coating. An entire surface of
the glass may be directly coupled to an entire surface of the
optically transmissive adhesive coating.
Inventors: |
WU; Weng-Jin; (Hsinchu City,
TW) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SEMICONDUCTOR COMPONENTS INDUSTRIES, LLC |
Phoenix |
AZ |
US |
|
|
Assignee: |
SEMICONDUCTOR COMPONENTS
INDUSTRIES, LLC
Phoenix
AZ
|
Family ID: |
67909164 |
Appl. No.: |
16/536971 |
Filed: |
August 9, 2019 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
15944634 |
Apr 3, 2018 |
10418396 |
|
|
16536971 |
|
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H01L 27/14632 20130101;
H01L 27/1469 20130101; H01L 27/14636 20130101; H01L 27/14618
20130101; H01L 27/14687 20130101; H01L 27/14634 20130101 |
International
Class: |
H01L 27/146 20060101
H01L027/146 |
Claims
1. A semiconductor package comprising: an image sensor; an
optically transmissive adhesive coating directly coupled to the
image sensor; and a optically transmissive lid coupled directly
coupled to the optically transmissive adhesive coating; wherein an
entire surface of the optically transmissive lid is directly
coupled to an entire surface of the optically transmissive adhesive
coating.
2. The package of claim 1, further comprising a single
redistribution layer (RDL) coupled to a second side of the image
sensor.
3. The package of claim 2, further comprising a plurality of
through vias (TV) comprised through the semiconductor package
electrically coupling the components of the semiconductor
package.
4. The package of claim 3, further comprising a plurality of bumps
coupled to the single RDL, wherein the plurality of bumps are
coupled with the plurality of TV.
5. The package of claim 4, further comprising: a first side of a
second semiconductor die coupled to a second side of the single
RDL; a mold compound comprised around the second semiconductor die;
a second RDL coupled to a second side of the second semiconductor
die.
6. The package of claim 1, wherein there is no cavity between the
optically transmissive lid and the image sensor due to the
optically transmissive adhesive coating.
7. A semiconductor package comprising: an image sensor; a optically
transmissive lid coupled to a first side of the image sensor
through an optically transmissive adhesive coating; a single
redistribution layer (RDL) coupled to a second side of the image
sensor; a plurality of through vias (TV) comprised through the
semiconductor package electrically coupling the components of the
semiconductor package; and a plurality of bumps coupled to the
single RDL, wherein the plurality of bumps are coupled with the
plurality of TV; wherein there is no cavity between the optically
transmissive lid and the image sensor due to the optically
transmissive adhesive coating.
8. The package of claim 7, further comprising: a first side of a
second semiconductor die coupled to a second side of the single
RDL; a mold compound comprised around the second semiconductor die;
a second RDL coupled to a second side of the second semiconductor
die.
9. The package of claim 8, wherein the mold compound extends to the
optically transmissive lid around one or more edges of the image
sensor.
10. The package of claim 8, further comprising: a third die coupled
to the second RDL; and a third RDL coupled to a second side of the
third die.
11. A semiconductor package comprising: an image sensor; an
optically transmissive adhesive coating directly coupled to the
image sensor; and an optically transmissive lid coupled directly
coupled to the optically transmissive adhesive coating; wherein any
space between the optically transmissive lid and the image sensor
is filled by the optically transmissive adhesive coating.
12. The package of claim 11, further comprising a single
redistribution layer (RDL) coupled to a second side of the image
sensor.
13. The package of claim 12, further comprising a plurality of
through vias (TV) comprised through the semiconductor package
electrically coupling the components of the semiconductor
package.
14. The package of claim 13, further comprising a plurality of
bumps coupled to the single RDL, wherein the plurality of bumps are
coupled with the plurality of TV.
15. The package of claim 14, further comprising: a first side of a
second semiconductor die coupled to a second side of the single
RDL; a mold compound comprised around the second semiconductor die;
a second RDL coupled to a second side of the second semiconductor
die.
16. The package of claim 11, wherein an entire surface of the
optically transmissive lid is directly coupled to an entire surface
of the optically transmissive adhesive coating.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional application of the earlier
U.S. Utility patent application to Wu entitled "Stacked Image
Sensor Package," application Ser. No. 15/944,634, filed Apr. 3,
2018, now pending, the disclosure of which is hereby incorporated
entirely herein by reference.
BACKGROUND
Technical Field
[0002] Aspects of this document relate generally to semiconductor
packages, such as image sensor chip scale packages. More specific
implementations involve stacked image sensor packages.
2. Background
[0003] Conventionally, image sensor packages include a gap or space
between the glass and the image sensor component of the package.
Some image sensor packages use wire bonding between the various
components.
SUMMARY
[0004] Implementations of semiconductor packages may include: an
image sensor; an optically transmissive transparent coating
directly coupled to the image sensor; and a glass lid coupled
directly coupled to the optically transmissive coating. An entire
surface of the glass may be directly coupled to an entire surface
of the optically transmissive adhesive coating.
[0005] Implementations of semiconductor packages may include: an
image sensor and a glass lid coupled to a first side of the image
sensor through an optically transmissive coating. The package may
also include a single redistribution layer (RDL) coupled to a
second side of the image sensor. The package may also include a
plurality of through vias (TV) included through the semiconductor
package electrically coupling the components of the semiconductor
package. The plurality of bumps may be coupled to the single RDL.
The plurality of bumps may be coupled with the plurality of TV. The
package may include no cavity between the glass lid and the image
sensor due to the optically transmissive adhesive coating.
[0006] Implementations of semiconductor packages may include one,
all, or any of the following:
[0007] The package may further include a first side of a second
semiconductor die coupled to a second side of the single RDL, a
mold compound around the second semiconductor die, and a second RDL
coupled to a second side of the semiconductor die.
[0008] A mold compound may extend to the glass lid around one or
more edges of the image sensor.
[0009] The package may further include a third die coupled to the
second RDL and a third RDL coupled to a second side of the third
die.
[0010] Implementations of a method of forming semiconductor
packages may include: providing a semiconductor wafer comprising a
plurality of image sensors and applying an optically transmissive
adhesive coating to a first side of the semiconductor wafer. The
method may also include coupling a glass wafer to the first side of
the semiconductor wafer through the optically transmissive adhesive
coating. The method may also include thinning the semiconductor
wafer to a predetermined thickness. The method may also include
forming a first plurality of through vias (TVs) in the
semiconductor wafer. The method may also include forming a
redistribution layer (RDL) on the second side of the semiconductor
wafer and cutting between each of the plurality of image sensors
into the optically transmissive adhesive coating to form a scribe
line. The method may include coupling a second semiconductor die to
the first RDL and coupling a molding compound over at least the
second semiconductor die. The method may also include forming a
second plurality of TVs extending from the first RDL to a second
side of the molding compound extending from a second side of the
second semiconductor die to the second side of the molding
compound. The method may include forming a second redistribution
layer (RDL) over the molding compound, coupling a plurality of
bumps to the second RDL, and singulating a plurality of
semiconductor packages at the scribe line.
[0011] Implementations of methods of forming semiconductor packages
may include one, all, or any of the following:
[0012] Applying the optically transmissive adhesive coating may
include applying one or more layers of the optically transmissive
adhesive coating.
[0013] The glass wafer may be bare glass.
[0014] The glass wafer may be coated glass.
[0015] The second semiconductor die may include a passive device,
an active device, an image sensor processor, a memory sensor, a
sensor, or any combination thereof.
[0016] The second semiconductor die may have a width that is
smaller than a width of the image sensor.
[0017] The plurality of bumps may include copper pillars or solder
bumps.
[0018] A method for forming a semiconductor package may also
include coupling a third semiconductor die to the second RDL layer
and applying a third molding compound over the third semiconductor
die. The method may also include forming a third set of TVs to
electrically couple the third semiconductor die with the image
sensor, the second semiconductor die, and a third RDL formed on the
second side of the third semiconductor die.
[0019] Implementations of a method of forming semiconductor
packages may include: providing a semiconductor wafer including a
plurality of image sensors; singulating the plurality of image
sensors; providing a glass wafer; applying an optically
transmissive adhesive coating to a first side of the glass wafer;
and coupling each of the plurality of image sensors to the
optically transmissive adhesive coating comprised on the glass
wafer. The method may also include applying a first molding
compound around the plurality of image sensors surrounding at least
three sides of the plurality of image sensors; thinning the
plurality of image sensors and the molding compound; and forming a
first plurality of through vias (TVs) through the plurality of
image sensors. The method may also include forming a first
redistribution layer on each of the plurality of image sensors;
coupling a plurality of die to the plurality of image sensors;
applying a second layer of molding compound over at least three
sides of each of the plurality of die; forming a second plurality
of through vias (TV) between the first redistribution layer and an
edge of the second layer of molding compound between a second side
of each of the plurality of die and the edge of the second layer of
molding compound. The method may also include forming a second
redistribution layer over the edge of the second layer of molding
compound and coupling a plurality of balls to the second
redistribution layer. The plurality of balls may be electrically
coupled with the plurality of second die and the plurality of image
sensors through the first plurality of TVs and through the second
plurality of TVs. The method may also include singulating between
each of the plurality of image sensors to form a plurality of
semiconductor packages.
[0020] Implementations of methods of forming semiconductor packages
may include one, all, or any of the following:
[0021] The method may include applying one or more layers of the
optically transmissive adhesive coating.
[0022] The glass wafer may include bare glass or coated glass.
[0023] The second semiconductor die may include a passive device,
an active device, an image sensor processor, a memory sensor, a
sensor, or any combination thereof.
[0024] The second semiconductor die may have a width that is
smaller than a width of the image sensor.
[0025] The plurality of bumps may include copper pillar or solder
bumps.
[0026] The method may also include coupling a third semiconductor
die to the second RDL layer; applying a third molding compound over
the third semiconductor die; and forming a third set of through
vias to electrically couple the third semiconductor die with the
image sensor, the second semiconductor die, and a third
redistribution layer formed on the second side of the third
semiconductor die.
[0027] The foregoing and other aspects, features, and advantages
will be apparent to those artisans of ordinary skill in the art
from the DESCRIPTION and DRAWINGS, and from the CLAIMS.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] Implementations will hereinafter be described in conjunction
with the appended drawings, where like designations denote like
elements, and:
[0029] FIG. 1 is a cross sectional view of an implementation of a
semiconductor package;
[0030] FIG. 2 is a cross sectional view of another implementation
of a semiconductor package;
[0031] FIG. 3 is a cross sectional view of another implementation
of a semiconductor package;
[0032] FIG. 4 is a cross sectional view of another implementation
of a semiconductor package;
[0033] FIGS. 5A-5N is an implementation of a method of forming a
semiconductor package as described herein;
[0034] FIGS. 6A-6N is an implementation of a method of forming a
semiconductor package as described herein; and
[0035] FIG. 7A-7B is a flow art of various implementations of
semiconductor packages as described herein.
DESCRIPTION
[0036] This disclosure, its aspects and implementations, are not
limited to the specific components, assembly procedures or method
elements disclosed herein. Many additional components, assembly
procedures and/or method elements known in the art consistent with
the intended semiconductor package will become apparent for use
with particular implementations from this disclosure. Accordingly,
for example, although particular implementations are disclosed,
such implementations and implementing components may comprise any
shape, size, style, type, model, version, measurement,
concentration, material, quantity, method element, step, and/or the
like as is known in the art for such semiconductor package, and
implementing components and methods, consistent with the intended
operation and methods.
[0037] An implementation of a semiconductor device may include an
image sensor having an optically transmissive adhesive coating
directly coupled thereto. A glass lid is then directly coupled to
the optically transmissive coating where the entire surface of the
glass is directly coupled to the entire surface of the optically
transmissive coating. This results in an image sensor package that
does not have any cavity or space between the glass lid and the
surface of the image sensor. Referring to FIG. 1, an implementation
of a semiconductor package 2 having a stacked image sensor is
illustrated. In this particular implementation, the package 2
includes an image sensor 4 coupled to a glass lid 6. The glass lid
6 is coupled to the first side 8 of the image sensor 4 through an
optically transmissive adhesive coating 10. In various
implementations, the optically transmissive adhesive coating may
include a polymer material with a refractive index similar to
glass. In some implementations, the refractive index of the
optically transmissive adhesive coating may be about 1.5. The
optically transmissive adhesive coating may have good optical
transmission. After thermal process and reflow the optical
transmission of various implementations of optically transmissive
adhesive coating may be greater than 99%. By non-limiting example,
the optically transmissive coating may be transparent or
translucent. As illustrated in FIG. 1, there is no cavity or space
between the glass lid 6 and the image sensor 4 due to the optically
transmissive adhesive coating. This feature may prevent water
and/or air from entering into the space between the image sensor
and the glass lid and causing cracking/popcorning of the device. In
various implementations, another material may be used in place of
the glass lid such as, by non-limiting example, a translucent or
transparent polymer, sapphire, tempered glass, or any other
translucent or transparent material.
[0038] Referring again to FIG. 1, the semiconductor package 2 may
also include a single redistribution layer (RDL) 12 coupled to a
second side 14 of the image sensor 4. The components of the
semiconductor package are electrically coupled through a plurality
of through vias (TV) 16, which may be through silicon vias when
passing through a silicon die rather than the other materials of
the package. The TVs may include electrically conductive materials
such as metal to allow for electrical connection between the
components. A second semiconductor die 18 is coupled to a second
side of the single RDL 12. While a second semiconductor die 18 is
illustrated in this implementation and other implementations in
this document, various package implementations may not include a
second die, but just the image sensor.
[0039] The package also includes a molding compound 20 around the
second semiconductor die 18. In this particular implementation the
molding compound 20 extends along the sides of the package to a
portion/layer of the optically transmissive coating 10. In other
implementations, the molding compound may extend all the way to the
glass lid encapsulating both the image sensor and the optically
transmissive coating. In other implementations, the molding
compound may only extend to a second side of a first RDL of the
package. As illustrated in FIG. 1, the semiconductor package also
includes a second RDL 22 coupled to a second side of the second
semiconductor die 18 through the plurality of TV 16. A plurality of
bumps 24 are coupled to the single RDL. The plurality of bumps 24
are electrically coupled with the plurality of TV 16 throughout the
package.
[0040] Referring to FIG. 2, another implementation of a
semiconductor package 26 is illustrated. This semiconductor package
26 includes a second side of a glass lid 28 coupled with a first
side of an image sensor 30 through an optically transmissive
coating 32. The optically transmissive coating 32 may include one
or more layers of coating materials. The package also includes a
stacked chip 34 or second semiconductor die coupled to a first RDL
36. By non-limiting example, the stacked chip may be a passive
device, an active device, an image sensor processor, a sensor
including a memory sensor, or any combination thereof. In this
implementation, a molding compound 38 encapsulates the stacked chip
34, the image sensor 30, and the optically translucent adhesive
coating 32. A plurality of TV 40 are formed in the image sensor 30
and molding compound 38 in order to electrically couple the
components of the device. A second RDL 42 is coupled to a second
side of the molding compound 38 and a plurality of balls 44 are
coupled to the second side of the second RDL 42. In various
implementations, the semiconductor package may include a third die.
The third die may be coupled to the second side of the second RDL
and a third RDL may be coupled to a second side of the third die.
In such an implementation, the plurality of bumps may be coupled to
the second side of the third RDL and the plurality of TV may
electrically couple all the components of the device.
[0041] Referring to FIG. 3, another implementation of a
semiconductor package 46 is illustrated. This implementation
includes a glass lid 48 coupled directly to an optically
transmissive adhesive coating 50. As previously described, the lid
may be formed of various other transparent or translucent
materials. The optically transmissive adhesive coating 50 is
directly coupled to an image sensor 52. As illustrated the entire
surface of the glass lid 48 is directly coupled to the entire
surface of the optically transmissive coating 50 leaving
substantially no space between the two surfaces. In various
implementations, the glass lid may be coated glass or bare glass.
In this implementation, a second semiconductor die 54 is coupled to
a first RDL 56 on the second side of the image sensor 52. In this
implementation, the second semiconductor die has a smaller width
than the width of the image sensor. Because the width of the image
sensor 52 is the same as the width of the glass lid 48, in this
implementation, the molding compound 58 extends from the second RDL
60 to the first RDL 62 and does not extend to the glass 48 or
optically transmissive adhesive coating 50. In other
implementations, however, the second die may have the same width or
a larger width than the image sensor.
[0042] Referring to FIG. 4, another implementation of a
semiconductor package 64 is illustrated. This implementation
illustrates the second semiconductor die 66 having the same width
as the image sensor 68 and the optically transmissive adhesive
coating 70. The glass lid 72 extends past the width of these
components. The molding compound 74 extends from the second RDL 76
to the glass lid 72 completely encapsulating the second
semiconductor die 66, the image sensor 68, and the optically
transmissive adhesive coating 70 on all sides. The molding compound
covering the edges of the image sensor and second semiconductor die
may act a light block and prevent moisture from entering the
package to increase reliability of the device.
[0043] In this implementation, the first RDL 78 extends past the
edges of the image sensor 68 and TVs 80 extend from the first RDL
78 to the second RDL 76 in order to electrically couple the image
sensor 68 with the plurality of bumps 82 coupled to the second side
of the second RDL 76. By non-limiting example, the plurality of
bumps may include copper pillars, solder balls, and other
electrical connector types (pads, etc.) used to couple a
semiconductor package with a motherboard or other electrical
device.
[0044] Referring to FIG. 5A-5N, a package at various stages of an
implementation of a method for forming a semiconductor package is
illustrated. Shown in FIG. 5A, the method includes providing a
semiconductor wafer 84 including a plurality of image sensors. The
semiconductor wafer may include silicon or may be made of any of a
wide variety of other semiconductor substrate types, such as, by
non-limiting example, silicon on insulator, gallium arsenide,
silicon carbide, sapphire, ruby, or any other semiconductor
substrate type. As illustrated in FIG. 5B, the method includes
applying an optically transmissive adhesive coating 86 to a first
side of the semiconductor wafer 84 over the image sensors formed
thereon. In FIG. 5C, a glass wafer 88 is then coupled to the first
side of the wafer 84 through and over the optically transmissive
adhesive coating 86. Referring to FIG. 5D, the wafer 84 coupled to
the glass lid 88 through the optically transmissive adhesive
coating 86 is flipped for further processing. As illustrated in
FIG. 5E, the backside of the wafer 84 is thinned. The wafer may be
thinned through any suitable thinning method such as, by
non-limiting example, mechanical grinding, chemical mechanical
planarization (CMP), wet etching, and atmospheric downstream plasma
dry chemical etching (ADP DCE).
[0045] Referring to FIG. 5F, the method further includes forming a
first plurality of TVs 90 in the semiconductor wafer 84. The TVs
may include metal for electrical connectivity, and since these TVs
are formed through the silicon of the wafer, they are through
silicon vias. As illustrated in FIG. 5G, the method includes
forming a RDL 92 on the second side of the semiconductor wafer 84.
The RDL may help with routing of signals throughout the package and
device. The RDL may include dielectric materials as well formed of,
by non-limiting example, polyimide, benzocyclobutene (BCB), other
suitable polymers, or any other dielectric material. In various
implementations, the RDL includes metal and may include metal
traces to electrically couple with metal in TVs.
[0046] Referring to FIG. 5H, the method includes cutting between
each of the plurality of image sensors 84 into the optically
transmissive adhesive coating 86 to form a scribe line 94. By
non-limiting example, the cutting may be performed through using
sawing. As illustrated in FIG. 5I, the method includes coupling a
second semiconductor die 96 to the first RDL 92. In various
implementations, the second semiconductor die may include a passive
device, an active device, an image sensor processor, a memory
sensor, a sensor, or any combination thereof. Coupling may be done
through any of a wide variety of die adhesion techniques,
including, by non-limiting example, solder, chip adhesives, die
attach film, electrically conductive materials, thermally
conductive materials, epoxies, or any other material capable of
adhering/coupling the die to the RDL material. As illustrated in
FIG. 5J, the method includes coupling a molding compound over at
least the second semiconductor die 96. In this particular
implementation, the molding compound 98 extends into the scribe
line 94 formed through cutting. The molding compound 98 also
encapsulates the image sensors 84 and extends into the optically
transmissive adhesive coating layer 86. In this way, the molding
compound may protect the device from moisture and increase
reliability of the device.
[0047] Referring to FIG. 5K, the method includes forming a second
plurality of TV 100 in the molding compounding. The second
plurality of TVs 100 extend from the first RDL 92 to a second side
of the molding compound 98. The second plurality of TVs 100 also
extend from a second side of the second semiconductor die 96 to the
second side of the molding compound 98. The second plurality of TVs
100 electrically couple the components of the semiconductor package
through a second redistribution layer 102 formed over the molding
compound 98 as illustrated in FIG. 5L.
[0048] Referring to FIG. 5M, the method includes coupling a
plurality of bumps 104 to the second RDL 102. The plurality of
bumps may include solder bumps, copper pillars, and other
electrical connector types, such as pads, etc. The plurality of
bumps may electrically couple with the components of the device
through the first plurality of TVs 90 and the second plurality of
TVs 100. As illustrated in FIG. 5N, the method includes singulating
a plurality of semiconductor packages 106 at the scribe lines. This
may be done using sawing, water jet cutting, etching, or other
singulation techniques. In various implementations, the method may
include coupling a third semiconductor die to the second RDL (using
any of the material types disclosed in this document) and applying
a second molding compound over the third semiconductor die. The
method may also include forming a third set of TVs to electrically
couple the third semiconductor die with the image sensor, the
second semiconductor die, and a third redistribution layer formed
on the second side of the third semiconductor die.
[0049] Referring to FIG. 6A-6N, a semiconductor package at various
points in an implementation of a method for forming semiconductors
as described herein is illustrated. Referring to FIG. 6A-6B, the
method includes providing a semiconductor wafer 108 having a
plurality of image sensors 110 and singulating the plurality of
image sensors 110. The wafer may be any semiconductor substrate
type disclosed in this document. Referring to FIG. 6C, the method
includes providing a glass wafer 112 which may be coated glass or
bare glass. In some implementations, the coated glass can have a
single side coated or both sides coated. The coating material may
provide protection to the glass from breaking or scratching. The
coating material may also act as an anti-reflection barrier. The
method further includes applying an optically transmissive adhesive
coating 114 to a first side of the glass wafer 112. One or more
layers of coating may be added between the plurality of image
sensors and the glass wafer in various method implementations. The
additional layers of coating may increase bonding between the
plurality of image sensors and the glass wafer 112. The additional
layers may also increase the optical function of the image sensors.
In various implementations, a bonding process may be performed on
the plurality of image sensors and the glass wafer after the
optically transmissive adhesive coating 114 is applied.
[0050] As illustrated in FIG. 6D, the method includes coupling each
of the plurality of image sensors 110 to the optically transmissive
adhesive coating 114 on the glass wafer 112. As illustrated in FIG.
6E, the method includes applying a first molding compound 116
around the plurality of image sensors 110 surrounding at least
three sides of the plurality of image sensors. Referring to FIG.
6F, the method includes thinning the plurality of image sensors 110
and the molding compound 116. The wafer may be thinned through any
suitable thinning method such as, by non-limiting example,
mechanical grinding, chemical mechanical planarization (CMP), wet
etching, and atmospheric downstream plasma dry chemical etching
(ADP DCE). The plurality of image sensors may be thinned several
tens of microns or up to about 100 microns in various
implementations.
[0051] Referring to FIG. 6G, the method includes forming a first
plurality of TVs 118 through the plurality of image sensors 110.
The first plurality of TVs may be passivated/isolated from the
silicon and may include layers of metal to improve interconnection
between the components of the device (these are through silicon
vias in this case). As illustrated in FIG. 6H, the method includes
forming a first redistribution layer (RDL) 120 on each of the
plurality of image sensors 110. The first RDL 120 may include
solder mask, molding compound, or solder mask followed by molding
compound or any of the other RDL materials disclosed in this
document. The first RDL may have defined metal traces in various
implementations and may electrically couple with the metal in the
TVs.
[0052] As shown in FIG. 6I, the method includes coupling a
plurality of die 122 to the plurality of image sensors 110. A first
side of the plurality of die 122 may be coupled to the second side
of the plurality of image sensors 110 through/at the first RDL 120
using any of the die coupling materials disclosed in this document.
Each of the plurality of die may be smaller, the same size, or
larger than each of the plurality of image sensors. In various
implementations, each of the plurality of die may be placed metal
side facing away from the image sensor or metal side facing toward
the image sensor.
[0053] Referring to FIG. 6J, the method includes applying a second
layer of molding compound 124 over at least three sides of each of
the plurality of die 122. The method also includes forming a second
plurality of through silicon vias (TV) 126 between the first RDL
120 and an edge of the second layer of molding compound 124. The
second plurality of TV 126 may also be formed between the second
side of each of the plurality of die 122 and the edge of the second
layer of molding compound 124.
[0054] As shown in FIG. 6K, the method includes forming a second
RDL 128 over the edge of the second layer of molding compound 124.
The second RDL 128 may include any of the materials used in the
first RDL 120. Referring to FIG. 6L, the method includes coupling a
plurality of bumps 130 to the second redistribution layer 128. The
plurality of bumps 130 are electrically coupled with the plurality
of second die 122 and the plurality of image sensors 110 through
the first plurality of TVs and through the second plurality of TVs
126. The plurality of bumps may include solder balls or copper
bumps or any other electrical connector type disclosed in this
document. The solder balls may be coupled to the second
redistribution layer by ball drop or by solder paste. The solder
balls may be lead free solder such as SAC305 manufactured by
various companies such as American Iron and Metal of Montreal,
Canada. The copper bumps or copper pillars may have solder caps.
Referring to FIGS. 6M-6N, the method includes singulating between
each of the plurality of image sensors 110 through the molding
compound 124 to form a plurality of semiconductor packages 132.
Singulating may be performed using sawing or any other singulation
process disclosed herein.
[0055] As previously explained, in various implementations of a
method of forming semiconductor packages, the method may further
include coupling a third semiconductor die to the second RDL using
any of the die bonding materials disclosed herein and applying a
third molding compound over the third semiconductor die. The method
may further include forming a third set of TVs to electrically
couple the third semiconductor die with the image sensor, the
second semiconductor die, and a third redistribution layer formed
on the second side of the third semiconductor die. In other
implementations, more than three chips/dies may be included in the
package as required. An advantage of this method of forming
semiconductor packages is having fewer vertical height limitations
when compared with wire bonding connection methods.
[0056] Referring to FIGS. 7A-7B, a structure tree is illustrated
detailing various process options and combination that may be
implemented at each step of the method depending on structural
variations of the die, via, molding processes, electrical
connectors, etc. that involve the various implementations of
methods of forming semiconductor packages and various
implementations of semiconductor packages as described herein. Any
of these various process options can be employed in a wide variety
of options in various implementations.
[0057] In places where the description above refers to particular
implementations of semiconductors packages and implementing
components, sub-components, methods and sub-methods, it should be
readily apparent that a number of modifications may be made without
departing from the spirit thereof and that these implementations,
implementing components, sub-components, methods and sub-methods
may be applied to other semiconductor packages.
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