JP2010147200A - Solid-state imaging apparatus and method of manufacturing same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an solid-state imaging apparatus which reduces occurrence of stray light due to incidence of light from the side surface of a protection member and in which a failure is not caused due to a sealing resin sticking on the protection member. <P>SOLUTION: The solid-state imaging apparatus includes an image sensor chip 10 bonded to a package 12, the protection member 18 bonded to the light receiving surface of the image sensor 10, and the sealing resin 26 covering the periphery of the image sensor chip 10. The upper surface of the sealing resin 26 is positioned below the upper surface of the protection member 18, and the upper surface of the sealing resin 26 at a connection portion with the protection member 18 has smaller surface roughness than the upper surface of the sealing resin 26 at a portion other than the connection portion. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a solid-state imaging device and a manufacturing method thereof.

In order to prevent image sensor chip deterioration due to outside air, a solid-state imaging device is known in which a transparent protective member such as glass is directly bonded on the light receiving surface of an image sensor chip. Furthermore, the image sensor chip to which the protective member is bonded is mounted on the substrate of the package, and the image sensor chip is sealed by filling a sealing resin between the image sensor chip and the package frame. An apparatus is known (see, for example, Patent Document 1). By filling the sealing resin, the image sensor chip can be hermetically sealed and protected from the outside air, and can be firmly fixed to the package. In addition, it is possible to protect the bonding wire that electrically connects the image sensor chip and the substrate.
JP 61-123288 A

  However, the solid-state imaging device has the following problems. First, as shown in FIG. 4A, the sealing resin 107 may not reach the side surface of the protective member 105 sufficiently. In this case, light shielding is insufficient, and light incident from the side surface of the protective member 105 becomes stray light, and the light receiving unit 101A of the image sensor chip 101 may detect abnormal light and cause image quality degradation such as ghost and flare. . Further, when the filling amount of the sealing resin 107 is increased so as to completely cover the side surface of the protective member 105, the sealing resin is formed on the effective pixel area at the edge of the protective member 105 as shown in FIG. May get on. Further, the sealing resin may adhere on the protective member 105. When the sealing resin 107 exists on the effective pixel area of the protective member 105, incident light is blocked and light reception failure occurs. Furthermore, as shown in FIG. 4C, there is a case in which an optical component 109 such as an optical filter or a prism is directly mounted on the protective member 105 on the camera set side. In this case, even if a sealing resin having a minute size of about 5 μm adheres outside the pixel effective pixel area, there is a possibility that image quality failure may occur due to optical tilt.

  The present invention solves the above-described problem, reduces the generation of stray light due to the incidence of light from the side surface of the protective member, and does not cause a defect due to the sealing resin adhering to the protective member. The purpose is to make it possible.

  In order to achieve the above-described object, the present invention is configured such that the solid-state imaging device has a surface roughness that is smaller than that of the other portions at the interface between the protective member and the sealing resin, and almost no steps.

  Specifically, a solid-state imaging device according to the present invention includes an image sensor chip bonded to a package and having a light receiving surface, a protective member bonded to the light receiving surface of the image sensor chip, and a seal covering the periphery of the image sensor chip. And the position of the upper surface of the sealing resin is equal to or lower than the position of the upper surface of the protective member, and the upper surface of the connecting portion with the protective member in the sealing resin is higher than the upper surface of the sealing resin other than the connecting portion. The surface roughness is small.

  In the solid-state imaging device of the present invention, the upper surface of the connection portion with the protective member in the sealing resin has a smaller surface roughness than the upper surface other than the connection portion of the sealing resin. That is, the portion formed on the protective member of the sealing resin is polished. For this reason, the side surface of the protective member is almost completely covered with the sealing resin, and the sealing resin does not remain on the protective member. Accordingly, it is possible to improve light reception failure due to the sealing resin on the protective member. Further, when an optical component such as a filter is directly bonded on the protective member, optical tilt or the like is hardly generated.

  In the solid-state imaging device of the present invention, the upper surface of the connection portion in the sealing resin may have a higher height than the upper surface other than the connection portion of the sealing resin.

  The method for manufacturing a solid-state imaging device according to the present invention includes the step (a) of adhering an image sensor chip having a protective member bonded to a light receiving surface to a package, and an image sensor so that at least part of the image sensor chip covers the protective member. A step (b) of filling a sealing resin between the chip and the package, and a step (c) of exposing the protective member by polishing and removing a portion of the sealing resin covering the protective member. In the step (c), the surface roughness of the upper surface of the connecting portion of the sealing resin with the protective member is made smaller than that of the upper surface of the sealing resin other than the connecting portion.

  In the method for manufacturing a solid-state imaging device according to the present invention, the sealing resin is filled so that at least a part thereof covers the protective member, and the portion covering the protective member of the sealing resin is removed by polishing. For this reason, the side surface of the protective member is almost completely covered with the sealing resin, and the sealing resin does not remain on the protective member. Accordingly, it is possible to manufacture a solid-state imaging device that does not cause poor light reception and poor image quality due to the sealing resin present on the protective member.

  In the method for manufacturing a solid-state imaging device of the present invention, in the step (b), the sealing resin may cover the entire surface of the protective member.

  According to the solid-state imaging device and the method for manufacturing the same according to the present invention, generation of stray light due to incidence of light from the side surface of the protective member is reduced, and a defect due to the sealing resin adhering to the protective member does not occur. A solid-state imaging device can be realized.

  1A and 1B show a solid-state imaging device according to an embodiment of the present invention. FIG. 1A shows a planar configuration, and FIG. 1B shows a cross-sectional configuration taken along line Ib-Ib in FIG. . As shown in FIG. 1, the image sensor chip 10 is bonded to a package 12 including a wiring board 12 </ b> A and a frame body 12 </ b> B through an adhesive 14. The image sensor chip 10 includes a photoelectric conversion unit 10A, and a protective member 18 is bonded via a transparent adhesive 16 on a light receiving surface on which the photoelectric conversion unit 10A is formed. The protection member 18 is made of a material that is transparent to the wavelength of received light, such as glass. The chip electrode 20 formed on the image sensor chip 10 and the wiring electrode 22 formed on the wiring board 12 </ b> A are connected by a bonding wire 24.

  A sealing resin 26 is filled around the image sensor chip 10 in the package 12. The height of the upper surface of the sealing resin 26 at the connecting portion with the protective member 18 is substantially equal to that of the protective member 18, and there is almost no step between the protective member 26 and the sealing resin. For this reason, it can suppress that the light used as a stray light enters from the side surface of the protection member 18.

  When manufacturing the solid-state imaging device of this embodiment, first, as shown in FIG. 2A, the image sensor chip to which the protective member 18 is bonded is bonded and fixed to the package 12, and then the chip electrode 20 and the wiring are connected. The electrode 22 is connected by a bonding wire 24.

  Next, as shown in FIG. 2B, a sealing resin 26 is filled around the portion of the package 12 where the image sensor chip 10 is bonded. At this time, the sealing resin 26 rides on the end portion of the protection member 18. When filling the sealing resin 26, the syringe 28 containing the sealing resin may be filled while being moved along the periphery of the image sensor chip. Next, as shown in FIG. 2C, the polishing device 30 is used to polish the portion of the sealing resin 26 that rides on the protective member 18 to expose the entire protective member 18. At the time of polishing, the height of the upper surface of the connection portion of the sealing resin 26 with the protection member 18 is made substantially equal to that of the protection member 18 so that there is almost no step at the connection portion between the protection member 18 and the sealing resin 26. To.

  Due to the difference in the polishing rate between the protective member 18 and the sealing resin 26, the polishing rate at the connection portion of the sealing resin 26 to the protective member 18 is smaller than the polishing rate at the other part of the sealing resin. For this reason, the sealing resin 26 is higher in the height of the connecting portion with the protection member 18 than in other portions. Further, the surface roughness at the connecting portion with the protective member 18 is smaller than other portions, and the smoothness is enhanced. The surface roughness is a parameter represented by, for example, the maximum height Rmax, the arithmetic average roughness Ra, or the ten-point average roughness Rz.

  In the solid-state imaging device of the present embodiment, the height of the upper surface of the connection portion of the sealing resin 26 with the protective member 18 can be substantially equal to the height of the upper surface of the protective member 18. There is almost no step between the two. For this reason, it becomes possible to prevent the incidence of light from the side surface of the protective member 18, and to solve the problem of image quality degradation such as ghost and flare. Further, the sealing resin 26 does not remain on the upper surface of the protection member 18, and optical components such as prisms and optical filters can be directly mounted on the surface of the protection member 18 without optical tilt. Furthermore, since the height of the upper surface of the sealing resin 26 other than the connection portion with the protective member 18 is lower than the upper surface of the connection portion, the optical component can be easily attached. When polishing the sealing resin 26, scratches generated on the upper surface of the protective member 18 and foreign matter that adheres firmly can be removed, so that the yield is improved and stable production is possible.

  In this embodiment, when the sealing resin 26 is filled, the sealing resin 26 covers only the end portion of the protective member 18. For this reason, there is an advantage that the polishing amount of the sealing resin 26 is small. Further, the height of the upper surface of the connection portion of the sealing resin 26 with the protective member 18 is higher than that of other portions. However, as shown in FIG. 3A, the sealing resin 26 may completely cover the protective member 18 when the sealing resin 26 is filled. In this case, as shown in FIG. 3B, when the sealing resin 26 is polished until the protective member 18 is exposed, the upper surface of the sealing resin 26 becomes substantially flat. However, even in this case, due to the difference in polishing rate between the sealing resin 26 and the protective member 18, the connection portion of the sealing resin 26 with the protective member 18 is less likely to be polished than the other portions of the sealing resin 26. For this reason, the upper surface of the connection portion between the sealing resin 26 and the protective member 18 is slightly higher than the other portions of the sealing resin 26. Further, the surface roughness of the upper surface of the connection portion with the protective member 18 is smaller than that of other portions.

  The sealing resin may be an epoxy resin. Further, it may be a biphenyl resin or a silicon resin. The filling of the sealing resin may be performed by transfer molding using a molding die. For example, a borosilicate glass plate may be used as the protective member. Moreover, in order to prevent moire due to interference fringes in a specific direction, a low-pass filter made of a quartz plate or a calcite plate having birefringence characteristics may be used. Further, a low-pass filter in which a quartz plate or a calcite plate is bonded so that birefringence characteristics are orthogonal to both sides of the infrared cut filter may be used. Further, it may be a transparent epoxy resin plate, an acrylic resin plate, or a transparent alumina plate.

  The solid-state imaging device and the manufacturing method thereof according to the present invention reduce the generation of stray light due to the incidence of light from the side surface of the protective member, and do not cause defects due to the sealing resin attached on the protective member. The present invention can be realized, and is particularly useful as a solid-state imaging device used for a digital camera, a digital video camera, and the like, and a manufacturing method thereof.

(A) And (b) shows the solid-state imaging device concerning one embodiment of the present invention, (a) is a top view and (b) is a sectional view in the Ib-Ib line of (a). (A)-(c) is sectional drawing which shows the manufacturing method of the solid-state imaging device concerning one Embodiment of this invention in order of a process. (A) And (b) is sectional drawing which shows the modification of the manufacturing method of the solid-state imaging device which concerns on one Embodiment of this invention in process order. (A)-(c) is sectional drawing which shows the problem which arises in the conventional solid-state imaging device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Image sensor chip 10A Photoelectric conversion part 12 Package 12A Wiring board 12B Frame 14 Adhesive material 16 Transparent adhesive material 18 Protection member 20 Chip electrode 22 Wiring electrode 24 Bonding wire 26 Sealing resin 28 Syringe 30 Polishing apparatus

Claims (4)

An image sensor chip bonded to the package and having a light receiving surface;
A protective member bonded to the light receiving surface of the image sensor chip;
A sealing resin covering the periphery of the image sensor chip,
The position of the upper surface of the sealing resin is not more than the position of the upper surface of the protective member,
The solid-state imaging device, wherein an upper surface of a connection portion of the sealing resin with the protection member has a smaller surface roughness than an upper surface of the sealing resin other than the connection portion.   2. The solid-state imaging device according to claim 1, wherein an upper surface of the connection portion in the sealing resin is higher than an upper surface of the sealing resin other than the connection portion. A step (a) of bonding an image sensor chip having a protective member bonded to a light receiving surface to a package;
A step (b) of filling a sealing resin around the image sensor chip so that at least a part thereof covers the protection member;
A step (c) of exposing the protective member by polishing and removing a portion of the sealing resin that covers the protective member;
In the step (c), the surface roughness of the upper surface of the connecting portion of the sealing resin with the protective member is made smaller than the upper surface of the sealing resin other than the connecting portion of the sealing resin. Manufacturing method.   The method for manufacturing a solid-state imaging device according to claim 3, wherein in the step (b), the sealing resin covers the entire surface of the protective member.

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