Solid-state image sensor package, solid-state image sensor package assembly, and method for manufacturing solid-state image sensor package

Abstract

To provide a solid-state image sensor package with high imaging quality.SOLUTION: A solid-state image sensor package 1 according to one aspect of the present invention includes: a first transparent substrate 10; a second substrate 20 having an imaging part 21 that faces the first substrate 10; and a frame 30 interposed between the first substrate 10 and the second substrate 20 and arranged to surround the imaging part 21. The frame 30 includes: a central wall 31 defining the distance between the first substrate 10 and the second substrate 20; an inner surface wall 32 laminated inside the central wall 31 and joined to the first substrate 10 and the second substrate 20; and an outer surface wall 33 laminated outside the central wall 31 and joined to the first substrate 10 and the second substrate 20.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a solid-state imaging device package, a solid-state imaging device package assembly, and a method for manufacturing a solid-state imaging device package. [Background technology]

[0002] Solid-state imaging devices (solid-state imaging element packages) such as CMOS image sensors and CCD image sensors are used in digital cameras, smartphones, etc. In recent years, their use has increased due to their widespread use in surveillance cameras in automobiles and factories, and there is an increasing demand for them to be more compact and have higher resolution.

[0003] A solid-state imaging device package is a package in which an element substrate having an imaging unit (light receiving element) and a transparent substrate such as glass are bonded together at a distance by a frame that surrounds the imaging unit, and which has a hollow space that contains the imaging unit. A solid-state imaging device package is manufactured by applying an adhesive whose main component is epoxy resin, acrylic resin, or the like to the element substrate to a certain thickness to form a frame, and then sealing the upper opening of the frame with a transparent substrate (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2004-296453 Summary of the Invention [Problem to be solved by the invention]

[0005] In the manufacturing process of conventional solid-state imaging element packages, when a transparent substrate is laminated to an element substrate via an adhesive, there is a risk that the adhesive may be crushed by the weight of the transparent substrate, causing the transparent substrate to tilt, or that the adhesive may be pushed out to the vicinity of the light-receiving element, thereby degrading imaging quality.

[0006] Therefore, an object of the present invention is to provide a solid-state imaging device package with high imaging quality, a solid-state imaging device package assembly, and a method for manufacturing the same. [Means for solving the problem]

[0007] (1) A solid-state imaging element package according to one embodiment of the present invention comprises a transparent first substrate, a second substrate having an imaging section facing the first substrate, and a frame interposed between the first substrate and the second substrate and arranged to surround the imaging section, wherein the frame has a central wall that defines the distance between the first substrate and the second substrate, an inner surface wall that is stacked inside the central wall and joined to the first substrate and the second substrate, and an outer surface wall that is stacked outside the central wall and joined to the first substrate and the second substrate.

[0008] (2) In the solid-state imaging device package of (1), the central wall may be formed from a resin composition that does not contain a filler, and the inner wall and the outer wall may be formed from a resin composition that contains a filler.

[0009] (3) The solid-state imaging device package of (1) to (2) may further include a light-shielding film formed on the outer periphery of one main surface of the first substrate.

[0010] (4) In the solid-state imaging element package of (3), the light-shielding film may be formed on the surface of the first substrate facing the second substrate, and the center wall, the inner wall, and the outer wall may be joined to the first substrate via the light-shielding film.

[0011] (5) A solid-state imaging element package assembly according to one embodiment of the present invention has a plurality of solid-state imaging element packages (1) to (3), and the first substrate and the second substrate are formed as an integrated aggregate first substrate and aggregate second substrate, respectively, via a dicing space.

[0012] (6) A method for manufacturing a solid-state imaging element package according to one embodiment of the present invention is a method for manufacturing a solid-state imaging element package comprising: a transparent first substrate; a second substrate having an imaging portion; and a frame interposed between the first substrate and the second substrate and arranged to surround the imaging portion, the method comprising the steps of: forming a central wall on one main surface of the first substrate that defines the distance between the first substrate and the second substrate so as to surround the imaging portion; applying an adhesive to the second substrate so as to face the central wall; and forming an inner surface wall that is joined to the first substrate and the second substrate inside the central wall by the adhesive, and an outer surface wall that is joined to the first substrate and the second substrate outside the central wall, so as to insert the central wall into the adhesive.

[0013] (7) In the solid-state imaging element package manufacturing method of (6), the first substrate and the second substrate are provided as a collective first substrate and a collective second substrate, respectively, in which multiple substrates are integrated together, and the steps of forming the center wall, applying the adhesive, and joining the first substrate and the second substrate are performed using the collective first substrate and the collective second substrate, and the solid-state imaging element package manufacturing method may further include a step of dicing the solid-state imaging element package into individual pieces after the step of joining the first substrate and the second substrate.

[0014] (8) In the solid-state imaging device package manufacturing method according to (7) to (6), the center wall may be formed of a negative photosensitive resin. [Effects of the Invention]

[0015] According to the present invention, a solid-state imaging device package with high imaging quality can be provided. [Brief explanation of the drawings]

[0016] [Figure 1] 1 is a schematic plan view of a solid-state imaging device package according to an embodiment of the present invention; [Figure 2] 2 is a cross-sectional view of the solid-state imaging device package taken along line XX in FIG. 1. [Figure 3] 1 is a schematic plan view of a solid-state imaging device package assembly according to an embodiment of the present invention; [Figure 4] 5 is a cross-sectional view of the solid-state imaging device package assembly taken along line YY. [Figure 5] 3 is a flowchart showing the steps of a method for manufacturing a solid-state imaging device package according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0017] Hereinafter, embodiments of the present invention will be described with reference to the drawings. For convenience, hatching and component symbols may be omitted. Also, the dimensions of various components in the drawings have been adjusted for clarity. FIG. 1 is a schematic plan view of a solid-state imaging device package according to one embodiment of the present invention. FIG. 2 is a cross-sectional view of the solid-state imaging device package of FIG. 1 taken along line XX.

[0018] The solid-state imaging element package 1 comprises a transparent first substrate 10, a second substrate 20 having an imaging section 21 facing the first substrate 10, and a frame 30 interposed between the first substrate 10 and the second substrate 20 and arranged to surround the imaging section 21.

[0019] The first substrate 10 protects the imaging unit 21 and allows light to be incident on the imaging unit 21. Examples of materials for the first substrate 10 include glass, transparent ceramics such as sapphire, and transparent plastics such as acrylic resin and polycarbonate. Among these, transparent ceramics are preferred as the material for the first substrate 10 from the viewpoint of reliability, and glass is particularly preferred from the viewpoint of versatility. There are no particular limitations on the type of glass used for the first substrate 10, and examples include quartz glass, borosilicate glass, and alkali-free glass.

[0020] A light-shielding film 11 may be formed on the outer periphery of one main surface of the first substrate 10. The light-shielding film 11 defines an optical path through which light from a subject enters the imaging unit 21. While the light-shielding film 11 may be formed on one main surface of the first substrate 10, it is preferable to form the light-shielding film 11 on the main surface of the first substrate 10 facing the second substrate 20 in order to suppress not only light entering the internal space of the solid-state imaging device package 1 from the outside (the space defined by the first substrate 10, the second substrate 20, and the frame 30) but also light reflected inside the solid-state imaging device package 1 from being re-reflected by the first substrate 10 and entering the imaging unit 21. In this case, the frame 30 is bonded to the first substrate 10 via the light-shielding film 11. The light-shielding film 11 also functions as a surface treatment film that improves the adhesion of the first substrate 10 to the frame 30. This allows the frame 30, which has high formability, to be reliably bonded to the first substrate 10. Moreover, the light-shielding film 11 is preferably formed so as to overlap the frame 30 so as not to form a path of light that leads to the imaging unit 21 on the outside.

[0021] The light-shielding film 11 is formed from a resin composition containing a colorant. The light-shielding film 11 can be formed by any method, such as printing. However, by forming the light-shielding film 11 from a photosensitive resin composition, a light-shielding film 11 with a uniform thickness and an accurate planar shape can be formed using photolithography techniques. The photosensitive resin composition contains a resin component having a reactive group, such as an epoxy group or an acrylic group, and a photopolymerization initiator. Examples of colorants contained in the photosensitive resin composition include organic pigments, inorganic pigments, and dyes. From the viewpoint of heat resistance and colorability, it is preferable to use a pigment as the colorant. The colorant can be any color, such as red, yellow, or blue. However, a color that absorbs a wide range of wavelengths, typically black, is preferred to suppress lateral light incidence and internal light re-reflection.

[0022] Black pigments that absorb a wide range of wavelengths in the visible light region include black organic pigments and black inorganic pigments. Examples of black organic pigments include anthraquinone-based black pigments, perylene-based black pigments, azo-based black pigments, and lactam-based black pigments. Among these, perylene-based black pigments and lactam-based black pigments are preferred due to their excellent light-blocking properties. Examples of black inorganic pigments include carbon black and black low-order titanium oxynitride. Examples of inorganic pigments other than black include composite metal oxide pigments, titanium oxide, barium sulfate, lead sulfate, yellow lead, red iron oxide, ultramarine, Prussian blue, chromium oxide, antimony white, zinc sulfide, zinc, manganese purple, cobalt purple, and magnesium carbonate. Specific examples of chromatic pigments include Color Index (CI) Pigment Yellow 1, 10, and 83; CI Pigment Orange 2, 5, and 13; CI Pigment Red 1, 2, and 3; CI Pigment Green 7, 10, and 36; and CI Pigment Blue 1, 2, and 15. These pigments can be used alone or in various combinations. Examples of dyes include azo compounds, anthraquinone compounds, perylene compounds, perinone compounds, phthalocyanine compounds, carbonium compounds, and indigoid compounds.

[0023] The colorant content in the light-shielding film 11 is preferably 0.5% by mass or more and 30% by mass or less, more preferably 1.0% by mass or more and 20% by mass or less, and particularly preferably 1.5% by mass or more and 15% by mass or less. By setting the colorant content at or above the lower limit, the light transmittance of the light-shielding film 11 can be sufficiently reduced, thereby effectively suppressing flare and ghosting. Specifically, the light transmittance of the light-shielding film 11 at 500 nm is preferably 30% or less, more preferably 10% or less, and even more preferably 3% or less. Furthermore, by setting the colorant content at or below the upper limit, it is possible to prevent the colorant from remaining on the surface of the first substrate 10 after removing the photosensitive resin composition from areas not irradiated with light.

[0024] The thickness of the light-shielding film 11 is preferably 0.5 μm or more and 30 μm or less, and more preferably 1 μm or more and 10 μm or less. By making the thickness of the light-shielding film 11 equal to or more than the above-mentioned lower limit, sufficient light-shielding properties can be imparted. Furthermore, by making the thickness of the light-shielding film 11 equal to or less than the above-mentioned upper limit, it is possible to prevent errors in the thickness of the light-shielding film 11 from causing the first substrate 10 to be tilted relative to the second substrate 20.

[0025] The second substrate 20 is a structural member that supports the imaging unit 21 and is made of a material with sufficient rigidity. The second substrate 20 may be a substrate that holds a semiconductor element (chip) on which the imaging unit 21 is formed, or may be a semiconductor wafer on which the imaging unit 21 is formed. The second substrate 20 may also be a simple support that does not have any components that are electrically incorporated into a circuit, but is preferably a circuit board on which a circuit that supplies power to the imaging unit 21 and extracts signals from the imaging unit 21 is formed. In this embodiment, the second substrate 20 is intended to be a circuit board on which a circuit including terminals for electrical connection with the imaging unit 21 is formed.

[0026] The imaging unit 21 may be a solid-state imaging element such as a CMOS image sensor. As described above, the imaging unit 21 may be integrated with the second substrate 20, but is typically an independent semiconductor element that has only an imaging function and is mounted on the second substrate 20. Wire bonding may be used as a method for mounting the imaging unit 21, which is an independent semiconductor element, on the second substrate 20, but flip-chip bonding is preferably used to reduce the size of the solid-state imaging element package 1.

[0027] Examples of materials for the second substrate 20 include resin materials such as polyimide, polyester, epoxy resin, bismaleimide triazine resin, and phenolic resin; composite materials in which these resins are impregnated into, for example, paper or glass fiber nonwoven fabric; ceramic materials such as alumina, aluminum nitride, beryllium oxide, and silicon nitride; and metal materials. Among these, glass epoxy substrates, ceramic substrates, and bismaleimide triazine resin substrates are preferably used as the second substrate 20. Furthermore, the second substrate 20 may be formed by forming a circuit having a metal wiring pattern or metal bumps on the surface or inside of these insulating substrates.

[0028] The frame 30 is an adhesive that secures the first substrate 10 and the second substrate 20 to each other, possibly via the light-shielding film 11. The frame 30 surrounds the imaging unit 21 with a gap therebetween so as to leave space around the imaging unit 21. Specifically, the frame 30 is preferably formed in the shape of a rectangular frame in a plan view.

[0029] The frame 30 has a central wall 31 that defines the distance between the first substrate 10 and the second substrate 20, an inner surface wall 32 that is stacked inside the central wall 31 and joined to the first substrate 10 and the second substrate 20, and an outer surface wall 33 that is stacked outside the central wall 31 and joined to the first substrate 10 and the second substrate 20. The frame 10 with this three-phase structure can hold the first substrate 10 and the second substrate 20 precisely parallel, reliably blocking light from the sides and effectively suppressing reflections on the inner surfaces. Therefore, the frame 30 suppresses unintended light from entering the imaging unit 21, improving imaging quality.

[0030] To prevent the frame 30 from protruding due to manufacturing errors while miniaturizing the solid-state imaging device package 1, the distance between the frame 30 and the outer edge of the first substrate 10 is preferably 1 μm to 1 mm, and more preferably 10 μm to 0.5 mm. To reliably block light and reliably bond the first substrate 10 and the second substrate 20 while miniaturizing the solid-state imaging device package 1, the average width of the frame 30 is preferably 100 μm to 500 μm, and more preferably 200 μm to 400 μm. To adequately prevent light from entering the imaging unit 21 at an angle, the height of the frame 30 is preferably 50 μm to 200 μm, and more preferably 80 μm to 150 μm.

[0031] To improve shape accuracy, the central wall 31 is preferably formed from a resin composition that does not contain fillers. The central wall 31 is preferably formed from a photosensitive resin so that it can be precisely formed using photography techniques, and is more preferably formed from a negative photosensitive resin from the standpoints of strength, adhesion, chemical resistance, film thickness range, and the like. In particular, the central wall 31 formed by photolithography using a negative photosensitive resin has a uniform height, making it possible to attach the first substrate 10 parallel to the second substrate 20. Examples of the negative photosensitive resin that can be used to form the central wall 31 include acrylic photosensitive resins, epoxy photosensitive resins, and siloxane photosensitive resins.

[0032] The thickness (width in plan view) of the center wall 31 is preferably 30 μm or more and 300 μm or less, and more preferably 50 μm or more and 200 μm or less, in order to miniaturize the solid-state imaging element package 1 while ensuring the strength to accurately determine the distance between the first substrate 10 and the second substrate 20.

[0033] The inner surface wall 32 exhibits adhesive strength to the first substrate 10 and the second substrate 20. For this reason, the frame 30 may be formed from an adhesive such as an epoxy adhesive, an acrylic adhesive, or a urethane adhesive. In particular, the inner surface wall 32 is preferably formed from a photosensitive adhesive that can be cured quickly enough to prevent deformation.

[0034] The inner wall 32 is a layer that suppresses light reflection on the inner surface of the frame 30 and contains a colorant that absorbs light and suppresses reflection. The colorant contained in the inner wall 32 may be the same as the colorant contained in the light-shielding film 11. The content of the colorant in the inner wall 32 is preferably 0.2% by mass or more and 20% by mass or less, more preferably 0.5% by mass or more and 15% by mass or less, and even more preferably 0.8% by mass or more and 10% by mass or less. By setting the content of the colorant at or above the lower limit, flare due to light reflection can be effectively suppressed. By setting the content of the colorant at or below the upper limit, the formability and adhesiveness of the inner wall 32 can be ensured.

[0035] The thickness of the inner wall 32 is preferably 30 μm to 300 μm, more preferably 50 μm to 200 μm, in order to reduce the size of the solid-state imaging device package 1 while ensuring suppression of reflection and adhesive strength.

[0036] The outer wall 33 exhibits adhesive strength to the first substrate 10 and the second substrate 20. The outer wall 33 also absorbs light to prevent it from transmitting through the frame 30. The outer wall 33 may be formed from the same material as the inner wall 32, and is preferably formed from the same material as the inner wall 32 in order to employ the manufacturing method described below.

[0037] The thickness of the outer wall 33 is preferably 30 μm to 300 μm, more preferably 50 μm to 200 μm, in order to ensure light blocking and adhesive strength while miniaturizing the solid-state imaging device package 1.

[0038] As described above, the solid-state imaging element package 1 having the frame 10 with a three-phase structure effectively suppresses the inclination of the first substrate 10 relative to the second substrate 20 and reliably suppresses the incidence of unintended light on the imaging section 21, resulting in excellent imaging quality.

[0039] 3 and 4, a plurality of solid-state imaging element packages 1 may be provided as an integrated solid-state imaging element package assembly 100. The solid-state imaging element package assembly 100 has a plurality of solid-state imaging element packages 1 arranged in a matrix, and the first substrate 10 and the second substrate 20 of the solid-state imaging element packages 1 are integrated via a dicing space S to form an integrated first substrate 110 and an integrated second substrate 120, respectively. Such a solid-state imaging element package assembly 100 is one embodiment of the solid-state imaging element package assembly according to the present invention.

[0040] The solid-state imaging device package 1 can be manufactured by an embodiment of a method for manufacturing a solid-state imaging device package according to the present invention shown in Fig. 5. The method for manufacturing a solid-state imaging device package shown in Fig. 5 includes a light-shielding film forming step (step S1), a center wall forming step (step S2), an adhesive applying step (step S3), a bonding step (step S4), and a dicing step (step S5).

[0041] In the light-shielding film forming step S1, a light-shielding film 11 is formed on the outer periphery of one main surface of a first substrate 10. The light-shielding film 11 can be formed by photolithography of a photosensitive resin composition, coating of a paint, or the like, but is preferably formed by photolithography of a photosensitive resin composition, which has high shape accuracy. Furthermore, to improve productivity, the first substrate 10 is provided as an aggregate first substrate 110 in which a plurality of first substrates 10 are integrated together.

[0042] In the center wall forming step S2, a center wall 31 is formed on the first substrate 10. The center wall 31 is preferably formed by photolithography using a negative photosensitive resin, which can be formed to a uniform height and a desired planar shape. Furthermore, a post-baking process may be performed in which the exposed photosensitive resin is further heated to completely harden it.

[0043] In the adhesive application step of step S3, an adhesive that forms the inner wall 32 and the outer wall 33 is applied to the second substrate 20. The adhesive can be applied by, for example, dispensing, screen printing, or other methods. In order to ensure the shape accuracy of the frame 30, the adhesive applied to the first substrate 10 may be semi-cured, for example, by exposing a photosensitive adhesive, before the subsequent bonding step. Furthermore, similar to the first substrate 10, the second substrate 20 is provided as an aggregate second substrate 120 in which a plurality of second substrates 20 are integrated together, in order to improve productivity.

[0044] In the bonding process of step S4, the first substrate 10 and the second substrate 20 are overlapped so that the center wall 31 is inserted into the adhesive applied to the second substrate 20, and the first substrate 10 and the second substrate 20 are bonded together using the adhesive applied to the second substrate 20. This results in a solid-state imaging device package assembly 100 in which multiple solid-state imaging device packages 1 are integrated and arranged side by side with dicing spaces between them. In the bonding process, the adhesive layer is penetrated through the center wall 31, and the tip of the center wall 31 is brought into contact with the second substrate 20, thereby determining the distance between the first substrate 10 and the second substrate 20 and accurately aligning the first substrate 10 parallel to the second substrate 20. Furthermore, because the frame 30 has a three-layer structure including the center wall 31, the inner wall 32, and the outer wall 33, unintended incidence of light on the imaging unit 21 can be effectively suppressed.

[0045] In the dicing step of step S5, the solid-state imaging element package assembly 100 obtained in the bonding step is diced to separate the solid-state imaging element packages 1. Dicing can be performed using a rotary blade such as a diamond cutter, for example.

[0046] As described above, by bonding the first substrate 10 and the second substrate 20 together so that the center wall 31 is inserted into the adhesive layer that forms the light-shielding inner wall 32 and outer wall 33, the distance between the first substrate 10 and the second substrate 20 can be accurately defined, and a solid-state imaging element package 1 with high imaging quality can be manufactured.

[0047] Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments and various modifications and variations are possible. The solid-state imaging device package according to the present invention may not have a light-shielding film. Furthermore, in the method for manufacturing a solid-state imaging device package according to the present invention, the first substrate and the second substrate may be bonded to each individual substrate without using an aggregate substrate. [Explanation of symbols]

[0048] 1 Solid-state imaging device package 10 First board 11 Light-shielding film 20 Second board 21 Imaging unit 30 frames 31 Center wall 32 Inner wall 33 Exterior wall 100 Solid-state imaging device package assembly 110 Group 1 board 130 Group 2nd board

Claims

1. a transparent first substrate; a second substrate having an imaging unit facing the first substrate; a frame interposed between the first substrate and the second substrate and disposed so as to surround the imaging unit; Equipped with The frame has a central wall that defines the distance between the first substrate and the second substrate, an inner surface wall that is stacked inside the central wall and joined to the first substrate and the second substrate, and an outer surface wall that is stacked outside the central wall and joined to the first substrate and the second substrate.

2. the central wall is formed from a resin composition that does not contain a filler; 2. The solid-state imaging device package according to claim 1, wherein the inner wall and the outer wall are formed from a resin composition containing a filler.

3. 3. The solid-state imaging device package according to claim 1, further comprising a light-shielding film formed on an outer periphery of one main surface of said first substrate.

4. the light-shielding film is formed on a surface of the first substrate facing the second substrate, 4. The solid-state imaging device package according to claim 3, wherein the central wall, the inner wall, and the outer wall are joined to the first substrate via the light-shielding film.

5. a plurality of solid-state imaging device packages according to claim 1 or 2; a solid-state imaging device package assembly, wherein the first substrate and the second substrate are respectively formed as an integrated first substrate and an integrated second substrate via a dicing space;

6. 1. A method for manufacturing a solid-state imaging device package including: a transparent first substrate; a second substrate having an imaging unit; and a frame interposed between the first substrate and the second substrate and disposed so as to surround the imaging unit, forming a center wall on one main surface of the first substrate so as to surround the imaging unit and define a distance between the first substrate and the second substrate; applying an adhesive to the second substrate so as to face the central wall; forming an inner surface wall bonded to the first substrate and the second substrate by the adhesive inside the central wall so as to insert the central wall into the adhesive, and an outer surface wall bonded to the first substrate and the second substrate outside the central wall; A method for manufacturing a solid-state imaging device package, comprising:

7. the first substrate and the second substrate are provided as a collective first substrate and a collective second substrate, respectively, in which a plurality of substrates are integrated; the step of forming the central wall, the step of applying the adhesive, and the step of joining the first substrate and the second substrate are performed using the aggregate first substrate and the aggregate second substrate; 7. The method for manufacturing a solid-state imaging device package according to claim 6, further comprising the step of dividing the solid-state imaging device package into individual pieces by dicing after the step of bonding the first substrate and the second substrate.

8. 8. The method for manufacturing a solid-state image pickup device package according to claim 6, wherein the central wall is formed of a negative photosensitive resin.

Images