JP2005184630A - Housing for storing semiconductor chip for image pickup device, and imaging device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a housing for storing a ball grid array type semiconductor chip for an imaging device with a lower intrusion speed of water from a through-hole and a long service lifetime of the device, and also to provide the imaging device. <P>SOLUTION: The housing for storing a ball grid array type semiconductor chip for the imaging device has a substrate, in which a circuit is formed on the surface, a resin molded part, which is molded into a box shape on the substrate by making the substrate as the bottom face, and the through-hole which achieves electrical conduction between the circuit on the substrate and the substrate face on the opposite side. The housing is characterized in that the through-hole is filled with a hole filler including a filler having hygroscopicity. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a housing for housing a semiconductor chip for an imaging apparatus with improved moisture resistance and an imaging apparatus.

  With the downsizing and high performance of semiconductor image sensors that convert captured images into electrical signals, the imaging devices are also miniaturized and used in various fields, increasing the convenience of the world, and downsizing the imaging devices. As a result, the market for video input sensors is expanding.

  As one means for reducing the size of such an imaging apparatus, the present inventors have disclosed in Japanese Patent Application No. 2002-229530 a case for housing a ball grid array type semiconductor chip for an imaging apparatus and imaging using the same casing. An invention relating to an apparatus is disclosed.

  However, in the ball grid array type imaging device as described above, since there is a through hole that achieves electrical continuity between the surface on which the circuit of the substrate is formed and the surface on the opposite side, moisture enters from the through hole. As a result, the corrosion of the semiconductor chip has progressed, and as a result, the lifetime of the imaging device has been shortened compared to the hermetic sealing type.

  In addition, as a countermeasure, a means of filling the through hole with a filling agent composed of a resin such as solder or epoxy resin and an inorganic filler is used, but in the case of solder, the through hole is completely filled because of its high viscosity. However, in the case of the hole filling agent, although the hole filling can be sufficiently performed, the moisture permeability is relatively large, and as a result, the water intrusion speed from the through hole is not necessarily sufficiently small.

  Accordingly, an object of the present invention is to provide a ball grid array type semiconductor chip housing case and an image pickup apparatus for an image pickup apparatus that have a low water intrusion speed from a through hole and a long apparatus life.

  As a result of intensive studies on this problem, the present inventors use a ball grid array type semiconductor chip housing case for an imaging device in which a through hole is filled with a hole filling agent containing a hygroscopic filler. As a result, the inventors have found that the above problems can be solved, and have completed the present invention.

  That is, a ball grid array type semiconductor chip housing for an image pickup apparatus according to the present invention includes a substrate having a circuit formed on a surface thereof, a resin molded portion formed in a box shape with the substrate as a bottom surface, and a substrate. A ball grid array type semiconductor chip housing case having a through hole that achieves electrical continuity between the upper circuit and the opposite substrate surface, the through hole containing a hygroscopic filler It is filled with a hole filling agent.

  According to the present invention, the speed of water intrusion into the imaging device is reduced. As a result, the corrosion of the semiconductor chip can be delayed and the life of the imaging device can be extended.

  FIG. 1 is a cross-sectional view of a ball grid array type semiconductor chip housing case for an image pickup apparatus according to the present invention, and FIG. 3 is a cross-sectional view of an image pickup apparatus manufactured using the case. The resin molding part 3 is molded by transfer molding, injection molding or the like using an epoxy resin molding material on the substrate 1 on which the circuit part 2 is formed with copper or the like (surface treatment is performed if necessary). Is done. Further, the substrate 1 is provided with through holes 4 for achieving electrical continuity between the circuit portion 2 and the opposite surface, and each through hole 4 is connected to any part of the circuit portion. .

  In the housing for housing a semiconductor chip for the ball grid array type imaging device of the present invention, the through hole 4 is filled with a filling agent 5 containing a hygroscopic filler. The through-hole filling agent 5 containing a hygroscopic filler is prepared by adding and kneading a hygroscopic filler to a commercially available through-hole filling agent.

  Examples of commercially available through-hole filling agents include PHP-900DC-5-4, PHP-900DC-3 manufactured by Yamaei Chemical Co., Ltd., and HBI-200DB4 manufactured by Taiyo Ink Manufacturing Co., Ltd. PHP-900DC-5-4 is preferable from the viewpoint of excellent effects of preventing water penetration when hole filling agents are compared.

  Examples of the hygroscopic filler include silica gel, zeolite, porous silica, and the like, and porous silica is preferred from the viewpoint of excellent kneadability into a commercially available through-hole filling agent. In addition, when porous silica is used, the amount added is 1 wt% or more with respect to the through-hole filling agent in order to obtain the effect of preventing the intrusion of water, and the addition increases the viscosity of the through-hole filling agent. In order to prevent the accompanying handling property fall, it is preferable to set it as 10 wt% or less.

  Examples of the method of kneading the hygroscopic filler into a commercially available through-hole filling agent include kneading with a roll, kneading with a planetary mixer, etc., but kneading with a planetary mixer is preferable from the viewpoint of ease of work. . When kneading with a planetary mixer, depending on the type of mixer, the type of commercially available through-hole filling agent, the type of hygroscopic filler and the amount added, it is usually kneaded for about 30 minutes. Thus, the through-hole filling agent and the hygroscopic filler can be uniformly kneaded.

  Filling the through hole of the housing for housing a semiconductor chip for a ball grid array type imaging device with the filling agent containing the prepared filler having hygroscopicity is performed by screen printing the filling agent from the back of the housing to the through hole portion. Thereafter, in order to cure the hole filling agent, necessary post-treatments such as UV irradiation and heating are performed. Thus, the housing for housing the semiconductor chip for the ball grid array type imaging device of the present invention is completed.

  Next, the semiconductor chip 6 is bonded to the substrate 1 via the chip adhesive sheet 7 made of polyimide resin, and the connection portion of the semiconductor chip and the circuit portion 2 are connected using the wire 8. Further, the glass lid 9 is bonded to the upper end of the resin molded portion using an adhesive, and then the resin barrel 10 fitted with the lens 11 is fixed to the connection portion 13 provided at the upper end of the resin molded portion with the adhesive. Is done. Finally, a solder paste is screen-printed on the through-hole part on the back of the case where the hole has been filled, and solder balls are formed by melting the solder using a reflow furnace, thereby completing the ball grid array type imaging device.

  Thereby, even if water contained in the atmosphere tries to enter from the through hole, it is adsorbed by the hygroscopic filler contained in the hole filling agent, and the infiltration speed is reduced.

  The ball grid array type semiconductor chip housing for an image pickup apparatus according to the present invention can be suitably used for a long-life, small-size and high-performance image pickup apparatus.

FIG. 3 is a schematic cross-sectional view of a ball grid array type semiconductor chip housing for an imaging device in which a through hole is filled with a hole filling agent containing a hygroscopic filler according to the present invention (AA in FIG. 2). cross section). FIG. 2 is a top view of FIG. 1 which is a housing for housing a semiconductor chip according to the present invention. It is the cross-sectional schematic of the imaging device produced using the housing | casing for semiconductor chip storage which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Board | substrate 2 Circuit part 3 Resin molding part 4 Through hole 5 Through hole hole filling agent 6 Semiconductor chip 7 Chip adhesion sheet 8 Wire 9 Glass lid 10 Lens tube 11 Lens 12 Solder ball 13 Connection part of resin lens tube

Claims (2)

  A substrate having a circuit formed on the surface thereof, a resin molded portion formed in a box shape with the substrate as a bottom surface thereon, and a through hole for achieving electrical conduction between the substrate surface opposite to the circuit on the substrate; A ball grid array type housing for semiconductor chip storage, wherein the through hole is filled with a hole-filling agent containing a hygroscopic filler. Housing for semiconductor chip storage.   An imaging apparatus using the housing for housing a semiconductor chip according to claim 1.

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