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 light shielding film 20 formed on the outer periphery of one main surface of the first substrate 10; a second substrate 30 having an imaging part 31 facing the first substrate 10; a frame 40 interposed between the first substrate 10 and the second substrate 30 and arranged to surround the imaging part 31; and three or more columnar bodies 50 buried in the frame 40 and defining the distance between the first substrate 10 and the second substrate 30.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 light-shielding film formed on the outer periphery of one main surface of the 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 arranged to surround the imaging unit, and three or more pillars embedded in the frame and defining the distance between the first substrate and the second substrate.

[0008] (2) In the solid-state imaging device package of (1), the frame may be formed in a rectangular frame shape, and the pillars may be disposed at corners of the frame.

[0009] (3) In the solid-state imaging device package of (2), a plurality of the pillars may be arranged at each of the corners.

[0010] (4) In the solid-state imaging element package of (1) to (3), the light-shielding film may be formed on the main surface of the first substrate facing the second substrate, and the frame and the columnar body 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 (4), 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 solid-state imaging element package manufacturing method 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 facing the first substrate; 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 light-shielding film on the outer periphery of one main surface of the first substrate; forming a plurality of pillars on the first substrate that are embedded in the frame and define the distance between the first substrate and the second substrate; applying an adhesive to the second substrate that forms the frame; and joining the first substrate and the second substrate with the adhesive so that the pillars are inserted 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 a plurality of substrates are integrated together, and the steps of forming the pillars, 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 packages into individual pieces after the step of joining the first substrate and the second substrate.

[0014] (8) In the method for manufacturing a solid-state imaging device package according to (6) to (7), the pillars may be formed from 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. FIG. 4 is a schematic plan view of a modified example of the solid-state imaging device package of FIG. [Figure 4] 1. FIG. 4 is a schematic plan view of a further modified example of the solid-state imaging device package of FIG. [Figure 5] 1 is a schematic plan view of a solid-state imaging device package assembly according to an embodiment of the present invention; [Figure 6] 5 is a cross-sectional view of the solid-state imaging element package assembly taken along line YY. [Figure 7] 1 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 device package 1 comprises a transparent first substrate 10, a light-shielding film 20 formed on the outer periphery of one main surface of the first substrate 10, a second substrate 30 having an imaging section 31 facing the first substrate 10, a frame 40 interposed between the first substrate 10 and the second substrate 30 and arranged to surround the imaging section 31, and three or more pillars 50 embedded in the frame 40 and defining the distance between the first substrate 10 and the second substrate 30.

[0019] The first substrate 10 protects the imaging unit 31 and allows light to be incident on the imaging unit 31. 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] The light-shielding film 20 defines an optical path through which light from a subject enters the imaging unit 31. The light-shielding film 20 may be formed on one main surface of the first substrate 10. However, it is preferable to form the light-shielding film 20 on the main surface of the first substrate 10 facing the second substrate 30 in order to suppress not only light that attempts to enter 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 30, and the frame 40) 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 31. In this case, the frame 40 and the columnar bodies 50 are bonded to the first substrate 10 via the light-shielding film 20. The light-shielding film 20 also functions as a surface treatment film that improves the adhesion of the first substrate 10 to the frame 40. This allows the frame 40, which has high moldability, to be reliably bonded to the first substrate 10. The light-shielding film 20 is preferably formed to overlap the frame 40 so as to prevent a light path from forming outside that leads to the imaging unit 31.

[0021] The light-shielding film 20 is formed from a resin composition containing a colorant. The light-shielding film 20 can be formed by any method, such as printing. However, by forming the light-shielding film 20 from a photosensitive resin composition, a light-shielding film 20 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 20 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 20 can be sufficiently reduced, thereby effectively suppressing flare and ghosting. Specifically, the light transmittance of the light-transmitting / shielding film 20 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 20 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 20 equal to or greater than the above-mentioned lower limit, sufficient light-shielding properties can be imparted. Furthermore, by making the thickness of the light-shielding film 20 equal to or less than the above-mentioned upper limit, it is possible to prevent errors in the thickness of the light-shielding film 20 from causing the first substrate 10 to be tilted relative to the second substrate 30.

[0025] The second substrate 30 is a structural member that supports the imaging unit 31 and is made of a material with sufficient rigidity. The second substrate 30 may be a substrate that holds a semiconductor element (chip) on which the imaging unit 31 is formed, or may be a semiconductor wafer on which the imaging unit 31 is formed. The second substrate 30 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 31 and extracts signals from the imaging unit 31 is formed. In this embodiment, the second substrate 30 is intended to be a circuit board on which a circuit including terminals for electrical connection with the imaging unit 31 is formed.

[0026] The imaging unit 31 may be a solid-state imaging element such as a CMOS image sensor. As described above, the imaging unit 31 may be integrated with the second substrate 30, but is typically an independent semiconductor element that has only an imaging function and is mounted on the second substrate 30. Wire bonding may be used as a method for mounting the imaging unit 31, which is an independent semiconductor element, on the second substrate 30, 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 30 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 30. Furthermore, the second substrate 30 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 40 is an adhesive that secures the first substrate 10 and the second substrate 30 to each other, possibly via the light-shielding film 20. The frame 40 surrounds the imaging unit 31 with a gap therebetween so as to leave space around the imaging unit 31. Specifically, the frame 40 is preferably formed in the shape of a rectangular frame in plan view.

[0029] The frame 40 may be formed from an adhesive such as an epoxy adhesive, an acrylic adhesive, or a urethane adhesive, and is preferably formed from a photosensitive adhesive that can harden quickly enough to prevent deformation. The frame 40 also preferably contains a colorant that absorbs light and suppresses reflection. The colorant contained in the frame 40 may be the same as the colorant contained in the light-shielding film 20.

[0030] The colorant content of the frame 40 is preferably 0.2% by mass to 20% by mass, more preferably 0.5% by mass to 15% by mass, and even more preferably 0.8% by mass to 10% by mass. By setting the colorant content at or above the lower limit, flare due to light reflection can be effectively suppressed. Furthermore, by setting the colorant content at or below the upper limit, the moldability and adhesiveness of the frame 40 can be ensured.

[0031] To prevent the frame 40 from protruding due to manufacturing errors while miniaturizing the solid-state imaging device package 1, the distance between the frame 40 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. Furthermore, to reliably block light and reliably bond the first substrate 10 and the second substrate 30 while miniaturizing the solid-state imaging device package 1, the average width of the frame 40 is preferably 100 μm to 500 μm, and more preferably 200 μm to 400 μm.

[0032] The pillars 50 are embedded in the frame 40, and define the distance between the first substrate 10 and the second substrate 30. In order to sufficiently prevent light from being incident obliquely on the imaging unit 31 by the frame 40, the height of the pillars 50 is preferably 50 μm or more and 200 μm or less, and more preferably 80 μm or more and 150 μm or less.

[0033] When the pillars 50 are inserted into the resin material layer forming the frame 40, the resin material forming the frame 40 is pushed outward, causing the inner peripheral surface of the frame 40 to bulge. If the inner peripheral surface bulges at the center of the side of the rectangular frame 40, light reflected from the bulging portion is likely to enter the imaging unit 31 and cause flare. For this reason, the pillars 50 are preferably selectively disposed at the corners of the frame 40, as in the modified example shown in FIG. 3. Specifically, the extent of the pillars 50 is preferably 30% or less of the length of each side of the frame 40, more preferably 20% or less, even more preferably 15% or less, and particularly preferably 5% or less. The shape of the pillars 50 is not particularly limited, but is preferably any of a rectangular pillar, a cylindrical shape, a pyramidal shape, and a cone, as these facilitate design and formation.

[0034] Furthermore, it is preferable to arrange a plurality of pillars 50 at each corner, as in the modified example shown in Fig. 4, in order to ensure a compressive strength that can accurately define the distance between the first substrate 10 and the second substrate 30, while reducing the cross-sectional area of ​​each pillar 50 to prevent degradation of image quality due to bulging of the frame 40. In particular, it is preferable to arrange four or more pillars 50 at each of the four corners.

[0035] In order to accurately define the distance between the first substrate 10 and the second substrate 30, the compressive strength of the columnar body 50 at 60°C is set to 0.1 N / cm 2 More than 0.1N / cm is preferable. 2 More preferably, 0.5N / cm 2 Furthermore, in order to ensure the strength of the columns 50 while suppressing the expansion of the frame 40, the area of ​​the end face of each column 50 on the second substrate 30 side is set to 25 μm 2 More than 1mm 2 Preferably less than 50 μm 2 More than 0.75mm 2 Less than 100 μm is more preferable 2 More than 0.5mm 2 The following is even more preferred:

[0036] The pillars 50 are preferably made of a cured product of a negative or positive photosensitive resin, since this makes it easy to set the shape of the pillars 50. Among these, a negative photosensitive resin is preferred as the material for forming the pillars 50 from the viewpoints of strength, adhesion, chemical resistance, film thickness range, etc., and among negative photosensitive resins, an acrylic photosensitive resin, an epoxy photosensitive resin, a siloxane photosensitive resin, etc. are particularly preferred.

[0037] As described above, the solid-state imaging device package 1 including the plurality of pillars 50 embedded in the frame 40 can effectively suppress tilt of the first substrate 10 relative to the second substrate 30, and therefore has excellent imaging quality.

[0038] 5 and 6, 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 30 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 130, 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.

[0039] 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. 7. The method for manufacturing a solid-state imaging device package shown in Fig. 7 includes a light-shielding film forming step (step S1), a columnar body forming step (step S2), an adhesive applying step (step S3), a bonding step (step S4), and a dicing step (step S5).

[0040] In the light-shielding film forming step S1, a light-shielding film 20 is formed on the outer periphery of one main surface of the first substrate 10. The light-shielding film 20 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.

[0041] In the column formation step S2, a plurality of columns 50 are formed on the first substrate 10. The columns 50 are 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 to completely cure the exposed photosensitive resin by heating.

[0042] In the adhesive application step of step S3, an adhesive that will form the frame 40 is applied to the second substrate 30. The adhesive can be applied by, for example, dispensing, screen printing, or other methods. To ensure the shape precision of the frame 40, the adhesive applied to the first substrate 10 may be semi-cured, for example, by exposing a photosensitive adhesive, before the subsequent bonding step. Similarly to the first substrate 10, the second substrate 30 is provided as an aggregate second substrate 130 in which multiple second substrates 30 are integrated together, in order to improve productivity.

[0043] In the bonding process of step S4, the first substrate 10 and the second substrate 30 are overlapped so that the pillars 50 are inserted into the adhesive applied to the second substrate 30, and the first substrate 10 and the second substrate 30 are bonded together using the adhesive applied to the second substrate 30. This results in a solid-state imaging device package assembly 100 in which multiple solid-state imaging device packages 1 are integrated and lined up with dicing spaces between them. In the bonding process, the pillars 50 are made to penetrate the adhesive layer so that the tips of the pillars 50 are brought into contact with the second substrate 30, thereby determining the distance between the first substrate 10 and the second substrate 30 and aligning the first substrate 10 accurately parallel to the second substrate 30.

[0044] 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.

[0045] As described above, by bonding the first substrate 10 and the second substrate 30 together so that multiple pillars 50 are inserted into the adhesive layer that forms the frame 40, the distance between the first substrate 10 and the second substrate 30 can be accurately defined, and a solid-state imaging element package 1 with high imaging quality can be manufactured.

[0046] While the present invention has been described above with reference to exemplary embodiments, it is not limited to the above-described embodiments and various modifications and variations are possible. 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]

[0047] 1 Solid-state imaging device package 10 First board 20 Light-shielding film 30 Second board 31 Imaging unit 40 frames 50 columnar body 100 Solid-state imaging device package assembly 110 Group 1 board 130 Group 2nd board

Claims

1. a transparent first substrate; a light-shielding film formed on the outer periphery of one main surface of the 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; three or more pillars embedded in the frame and defining a distance between the first substrate and the second substrate; A solid-state imaging device package comprising:

2. The frame is formed in a rectangular frame shape, The solid-state imaging device package according to claim 1 , wherein the pillars are arranged at corners of the frame.

3. The solid-state imaging device package according to claim 2 , wherein a plurality of the pillars are arranged at each of the corners.

4. the light-shielding film is formed on a main surface of the first substrate facing the second substrate, 4. The solid-state imaging device package according to claim 1, wherein the frame and the pillars are joined to the first substrate via the light-shielding film.

5. a plurality of solid-state imaging device packages according to any one of claims 1 to 3; 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, comprising: a transparent first substrate; a second substrate having an imaging unit facing the first substrate; and a frame interposed between the first substrate and the second substrate and disposed so as to surround the imaging unit, forming a light-shielding film on an outer periphery of one main surface of the first substrate; forming a plurality of pillars on the first substrate, the pillars being embedded in the frame and defining a distance between the first substrate and the second substrate; applying an adhesive to the second substrate to form the frame; bonding the first substrate and the second substrate with the adhesive so that the pillars are inserted into the adhesive; 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 pillars, the step of applying the adhesive, and the step of joining the first substrate and the second substrate are performed using the first aggregate substrate and the second aggregate 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 pillars are formed of a negative photosensitive resin.

Images