JP2008135982A - Solid-state imaging device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem that since conventional bonding constitution of an IR cut filter of a solid-state imaging device is such that a filter holding unit of a case is provided with a recessed part for preventing an adhesive from flowing out, the thickness of the filter holding unit of the case can not be made thin and the solid-state imaging device can not be made compact and thin. <P>SOLUTION: The solid-state imaging device has a circuit board mounted with an imaging element and the case covering the circuit board, and also has the filter holding unit holding the IR cut filter, the IR cut filter bonded to the filter holding unit, and a lens in the case, wherein the IR cut filter is provided with the recessed part or an opening for preventing an adhesive from flowing out. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a solid-state imaging device, and more particularly to an adhesive configuration of an IR cut filter of the solid-state imaging device.

  2. Description of the Related Art In recent years, as a small-sized imaging device used for a mobile phone, a digital camera, etc., it has a circuit board on which an imaging element such as a CMOS is mounted, and a casing that covers the circuit board. And a solid-state imaging device having a lens are widely used. (For example, refer to Patent Document 1.)

Hereinafter, a conventional solid-state imaging device will be described with reference to the drawings.
FIG. 14 and FIG. 15 schematically show the configuration of the imaging device in the portable device camera of Patent Document 1 so that the gist of the present invention can be easily understood. FIG. 14 is a cross-sectional view of the solid-state imaging device. 15 is an enlarged cross-sectional view of the IR cut filter adhesion portion A of FIG.

  In FIG. 14, 60 is a solid-state imaging device, 1 is a circuit board, 2 is an imaging device mounted on the circuit board 1, 3 is a housing, and the housing 3 includes an imaging window portion 3a, a filter holding portion 3b, A concave portion 3c for preventing the flow of the adhesive formed in the filter holding portion 3b is provided. Reference numeral 4 denotes an IR cut filter adhered to the filter holding portion 3b, which is obtained by performing an optical film treatment on a glass substrate. A holder 5 is slidably attached to the housing 3, and a lens 6 is attached to the holder 5.

Next, the assembly procedure of the solid-state imaging device 60 will be described.
An image sensor 2 such as a CMOS is mounted on the circuit board 1. The housing 3 is bonded and integrated with an IR cut filter 4 using an adhesive to the filter holding portion 3b, and a holder 5 fitted with a lens 6 is incorporated to constitute an optical device unit. The circuit board 1 and the housing 3 are bonded and integrated in a state where the positions of the lens 6 and the IR cut filter 4 constituting the optical device unit and the image pickup element 2 are adjusted to be solid-state image pickup. The device 60 is completed.

Next, a method for bonding the IR cut filter 4 to the housing 3 will be described.
As shown in FIG. 14, the IR cut filter 4 is bonded to the filter holding portion 3b while being positioned on the imaging window portion 3a of the housing 3. As shown in FIG. In the vicinity of the filter holding portion 3b of the body 3, a recess 3c for preventing the adhesive from flowing out is provided. In adhering, the adhesive 7 is applied to the outer peripheral surface 4a and the outer peripheral surface 4b of the IR cut filter 4, and the IR cut filter 4 is fitted and bonded to the filter holding part 3b.

  According to the above configuration, even if the application amount of the adhesive 7 is slightly different at the time of adhesion, and even if the application amount is non-uniform depending on the position, the applied adhesive 7 is applied to the IR cut filter 4. While the outer peripheral part upper surface 4a and the outer peripheral part end surface 4b are adhere | attached firmly, the excess adhesive agent 7 is absorbed by the recessed part 3c, and can prevent outflow. As a result, the adhesive 7 does not flow out to the imaging window 3a, which is an imaging area, and does not disturb the imaging function, and the IR cut filter 4 can be held in the correct position and in the correct position on the filter holding unit 3b. Further, since the management of the coating amount of the adhesive 7 becomes easier during the bonding operation, there is a manufacturing effect.

  In recent years, IR cut filters made of resin sheets have been put into practical use in addition to IR cut filters that have been optically coated on glass substrates. These IR cut filters made of resin sheets are used to make mobile phones and digital cameras thinner. Along with this, it is expected to be widely adopted. (For example, see Patent Document 2.)

Next, an IR cut filter using a conventional resin sheet will be described with reference to the drawings.
16 is a plan view of an IR cut filter using a resin sheet shown in Patent Document 2, and FIG. 17 is a cross-sectional view of the IR cut filter using a resin sheet shown in FIG. 16 and 17, 8 is a resin sheet IR cut filter, 8e is a spacer, and a ring-shaped spacer 8e is bonded and integrated around the resin sheet IR cut filter 8.

  That is, the resin sheet IR cut filter 8 can be thinned, but since it is a thin sheet, it is difficult to handle and causes a manufacturing problem. For this reason, a ring-shaped spacer 8e is bonded around the resin sheet IR cut filter 8 to make a resin sheet IR cut filter with an integrated spacer, which facilitates handling during manufacturing.

JP 2002-374439 A (FIG. 1) JP 2006-173855 A (FIG. 3)

  However, the conventional IR cut filter adhesive configuration shown in Patent Document 1 is a configuration in which the filter holding portion 3b of the housing 3 is provided with a recess 3c for preventing the adhesive from flowing out. Accordingly, the thickness of the molded resin of the housing 3 which is a resin molded product is also reduced, and the thickness of the filter holding portion 3b is also reduced to about 0.3 mm. Therefore, it is difficult to provide a recess for preventing the adhesive from flowing out in the thinned filter holding portion 3b, and it is desired to further reduce the thickness without providing the recess.

  Furthermore, in order to provide the recess 3c in the filter holding portion 3b of the housing 3, it is necessary to provide a projection for the recess in the molding die of the housing 3, which complicates the mold structure and allows the resin flow during molding. There is a problem that the molding conditions are deteriorated due to the inhibition.

  Further, since the resin sheet IR cut filter 8 shown in Patent Document 2 is a thin sheet of about 0.1 mm, it is possible to reduce the thickness of the solid-state imaging device. There was a problem that positioning and adhesion to the holding part were difficult.

  An object of the present invention is to provide a solid-state imaging device that is easy to bond a filter to a holding portion of a housing and has high reliability.

  In order to achieve the above object, the gist of the present invention is to have a circuit board on which an image sensor is mounted and a casing that covers the circuit board, and a filter holding portion in the casing and an adhesive to the filter holding portion. In the solid-state imaging device having the IR cut filter and the lens, a recess or an opening for preventing the adhesive from flowing out is formed in the IR cut filter.

  According to the above configuration, since the concave portion or opening for preventing the adhesive from flowing out is formed on the IR cut filter side, it is not necessary to provide the concave portion or the opening on the filter holding portion side of the housing, The structure of the filter holding part of the housing is simplified and the thickness can be reduced. Further, the manufacturing process can be facilitated by simplifying the molding die. Further, when it is necessary to replace the IR cut filter, since the flow-stopped adhesive remains in the recess or opening provided in the IR cut filter, it is removed together with the IR cut filter. No trace is left on the holding part side, and adhesion of a new IR cut filter becomes easy.

  The concave portion or the opening is a solid-state imaging device formed so as to surround a filter region in the IR cut filter.

  The concave portion is a solid-state imaging device formed in a ring shape around a filter region in the IR cut filter.

  The opening is a solid-state imaging device formed by arranging a plurality of openings around a filter region in the IR cut filter.

  In the solid-state imaging device, the adhesive of the IR cut filter adhered to the filter holding portion forms a large-diameter portion outside the opening.

  According to the said structure, since a thin IR cut filter can be firmly hold | maintained by a large diameter part, the reliability of an attachment structure can be improved.

  The IR cut filter is a solid-state imaging device formed of a resin sheet, and the concave portion is formed by thermoforming.

  According to the said structure, the recessed part of arbitrary shapes can be easily formed using the thermoforming characteristic of a resin sheet.

  The IR cut filter is a solid-state imaging device in which a glass substrate is used and the concave portion is formed by half dicing.

  According to the said structure, a frame-shaped recessed part can be easily formed in the IR cut filter of a glass substrate with the simple processing method called a half dicing process.

  As described above, the solid-state imaging device according to the present invention has a recess or opening for preventing the adhesive from flowing out in the IR cut filter, thereby enabling the filter holding portion to be thinned and attaching the IR cut filter. It is possible to achieve improved reliability and low manufacturing costs.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. 1 to 3 show a solid-state imaging device according to a first embodiment of the present invention, FIG. 1 is a cross-sectional view of the solid-state imaging device, and FIG. 2A is a plan view of an IR cut filter in FIG. An optical film treatment is performed on a glass substrate. 2B is a cross-sectional view taken along the line BB of the IR cut filter shown in FIG. 2A, and FIG. 3 is an enlarged cross-sectional view showing an adhesion portion A of the IR cut filter shown in FIG. The basic configuration and assembly method of the solid-state imaging device according to the first embodiment shown in FIGS. 1 to 3 are the same as those of the conventional solid-state imaging device shown in FIGS. 14 and 15, and common elements have the same numbers. A duplicate description is omitted.

  In FIG. 1, reference numeral 10 denotes a solid-state image pickup device. Unlike the solid-state image pickup device 60 shown in FIG. 14, the filter holding portion 3 b of the housing 3 is not provided with a recess 3 c for preventing the adhesive from flowing out. That is. In place of the recess 3c formed in the filter holding portion 3b, the IR cut filter 4 is provided with a recess 4c for preventing the adhesive from flowing out as shown in FIGS. 2 (a) and 2 (b). . The recess 4c of the IR cut filter 4 is formed in a ring shape so as to surround a filter region (indicated by a one-dot chain line) restricted by the imaging window 3a of the housing 3.

Next, a method for bonding the IR cut filter 4 to the housing 3 will be described.
As shown in FIG. 1, the IR cut filter 4 is bonded to the filter holding portion 3b while being positioned on the imaging window portion 3a of the housing 3. As shown in FIG. The cut filter 4 is provided with a recess 4c for preventing the adhesive from flowing out. In adhering, the adhesive 7 is applied, and the IR cut filter 4 is fitted and adhered to the filter holding portion 3b.

  According to the above configuration, even if the application amount of the adhesive 7 is slightly different at the time of adhesion, and even if the application amount is non-uniform depending on the position, the applied adhesive 7 is applied to the IR cut filter 4. The outer peripheral portion upper surface 4a and the outer peripheral portion end surface 4b are firmly bonded, and the excess adhesive 7 is absorbed by the concave portion 4c of the IR cut filter 4 to prevent outflow. As a result, the adhesive 7 does not flow out to the imaging window 3a, which is an imaging area, and does not disturb the imaging function, and the IR cut filter 4 can be held in the correct position and in the correct position on the filter holding unit 3b. Further, since the management of the coating amount of the adhesive 7 becomes easier during the bonding operation, there is a manufacturing effect. In addition, according to the configuration of the present invention, it is not necessary to provide the recess 3c for preventing the adhesive from flowing out in the filter holding portion 3b of the housing 3, so that the thickness T of the filter holding portion 3b is set as shown in FIG. Since the thickness can be reduced, it is possible to reduce the thickness expected for the solid-state imaging device 10.

  Next, a second embodiment of the present invention will be described with reference to the drawings. 4 to 6 show a solid-state imaging device according to a second embodiment of the present invention. FIG. 4 is a cross-sectional view of the solid-state imaging device, FIG. 5A is a plan view of the IR cut filter in FIG. 5 (b) is a BB cross-sectional view of the IR cut filter shown in FIG. 5 (a), and FIG. 6 is an enlarged cross-sectional view showing an adhesion portion A of the IR cut filter in FIG. The basic configuration and assembly method of the solid-state imaging device according to the second embodiment shown in FIGS. 4 to 6 are the same as those of the solid-state imaging device 10 according to the first embodiment shown in FIGS. Are given the same numbers, and redundant description is omitted.

    In FIG. 4, reference numeral 20 denotes a solid-state image pickup device. Unlike the solid-state image pickup device 10 shown in FIG. 1, the IR cut filter 4 of the solid-state image pickup device 10 is provided with a recess 4c for preventing the adhesive from flowing out. In contrast, the IR cut filter 4 of the solid-state imaging device 20 is provided with an opening 4d for preventing the adhesive from flowing out. That is, as shown in FIGS. 5A and 5B, the opening 4d of the IR cut filter 4 surrounds a filter region (indicated by a one-dot chain line) regulated by the imaging window portion 3a of the casing 3. A plurality are arranged side by side so as to surround them.

Next, a method for bonding the IR cut filter 4 to the housing 3 will be described.
As shown in FIG. 4, the IR cut filter 4 is bonded to the filter holding portion 3b while being positioned on the imaging window portion 3a of the housing 3. As shown in FIG. The cut filter 4 is provided with an opening 4d for preventing the adhesive from flowing out. When bonding, the adhesive 7 is applied, and the IR cut filter 4 is fitted and bonded to the filter holding portion 3b. The adhesive 7 applied in the same manner as the solid-state imaging device 10 is applied to the IR cut filter 4. The outer peripheral portion upper surface 4a and the outer peripheral end surface 4b are firmly adhered, and the excess adhesive 7 is absorbed by the opening 4d of the IR cut filter 4 to prevent outflow.

  Next, a third embodiment of the present invention will be described with reference to the drawings. 7 to 9 show a solid-state imaging device according to a third embodiment of the present invention. FIG. 7 is a sectional view of the solid-state imaging device, and FIG. 8A is a plan view of the resin sheet IR cut filter in FIG. 8B is a cross-sectional view taken along the line BB of the resin sheet IR cut fill shown in FIG. 8A, and FIG. 9 is an enlarged cross-sectional view showing the adhesion portion A of the resin sheet IR cut filter shown in FIG. The basic configuration and assembly method of the solid-state imaging device of the third embodiment shown in FIGS. 7 to 9 are the same as those of the solid-state imaging device 10 of the first embodiment shown in FIGS. Are given the same numbers, and redundant description is omitted.

    In FIG. 7, reference numeral 30 denotes a solid-state image pickup device. The solid-state image pickup device 30 is different from the solid-state image pickup device 10 shown in FIG. 1, whereas the IR cut filter 4 of the solid-state image pickup device 10 is formed of a glass substrate. Is that the resin sheet IR cut filter 8 is used. A concave portion 8 c for preventing the adhesive from flowing out is provided in the peripheral portion of the resin sheet IR cut filter 8. That is, as shown in FIGS. 8A and 8B, the recess 8c of the resin sheet IR cut filter 8 is a filter region (indicated by a one-dot chain line) regulated by the imaging window 3a of the housing 3. It is formed in a ring shape so as to surround the periphery. The resin sheet IR cut filter 8 uses a resin sheet having a thickness of 0.1 mm. As an example of a method for forming the recess 8c, the resin sheet IR cut filter 8 is formed by heat molding using the characteristics of a resin sheet having good moldability. It can be formed into an arbitrary shape.

  As shown in the enlarged cross-sectional view of FIG. 9, the bonding portion A of the resin sheet IR cut filter 8 in FIG. 7, the bonding method of the resin sheet IR cut filter 8 to the filter holding portion 3 b of the housing 3 by the adhesive 7 is described above. 1 is applied, the applied adhesive 7 firmly bonds the outer peripheral surface 8a and the outer peripheral end surface 8b of the resin sheet IR cut filter 8, and the excess adhesive 7 is a resin. The sheet IR cut filter 8 is absorbed in the concave portion 8c and can be prevented from flowing out.

  Next, a fourth embodiment of the present invention will be described with reference to the drawings. 10 to 12 show a solid-state imaging device according to a fourth embodiment of the present invention, FIG. 10 is a cross-sectional view of the solid-state imaging device, and FIG. 11A is a plan view of the resin sheet IR cut filter in FIG. 11 (b) is a cross-sectional view taken along the line BB of the resin sheet IR cut filter shown in FIG. 11 (a), and FIG. 12 is an enlarged cross-sectional view showing an adhesive portion A of the resin sheet IR cut filter shown in FIG. The basic configuration and assembly method of the solid-state imaging device of the fourth embodiment shown in FIGS. 10 to 12 are the same as those of the solid-state imaging device 30 of the third embodiment shown in FIGS. Are given the same numbers, and redundant description is omitted.

  10, reference numeral 40 denotes a solid-state image pickup device. Unlike the solid-state image pickup device 30 shown in FIG. 7, the resin sheet IR cut filter 8 of the solid-state image pickup device 30 has a recess 8c for preventing the adhesive from flowing out. In contrast, the resin sheet IR cut filter 8 of the solid-state imaging device 40 is provided with an opening 8d for preventing the adhesive from flowing out. That is, as shown in FIGS. 11A and 11B, the opening 8d of the resin sheet IR cut filter 8 is a filter region (indicated by a one-dot chain line) regulated by the imaging window 3a of the housing 3. A plurality are arranged side by side so as to surround the periphery.

As shown in the enlarged cross-sectional view of FIG. 12, the bonding portion A of the resin sheet IR cut filter 8 in FIG. 10, the bonding method of the resin sheet IR cut filter 8 to the filter holding portion 3 b of the housing 3 by the adhesive 7 is as described above. 9 is performed in the same manner as the solid-state imaging device 30 of FIG. 9, and the applied adhesive 7 firmly adheres the outer peripheral surface 8a and the outer peripheral end surface 8b of the resin sheet IR cut filter 8 and the extra adhesive 7 is a resin. The sheet IR cut filter 8 can absorb the opening 8d and prevent the outflow. Further, the excess adhesive 7 filled in the opening 8d forms a large-diameter portion 7a outside the opening 8d on the lower surface side of the resin sheet IR cut filter 8. The thin sheet-like resin sheet IR cut filter 8 can be firmly held on the filter holding portion 3b of the housing 3 by the large diameter portion 7a of the adhesive 7 formed outside the opening 8d.
Further, as shown in FIG. 11 (a), by forming a large number of openings 8d so as to surround the periphery of the filter region, the number of the large diameter portions 7a can be increased to hold the resin sheet IR cut filter 8. It is stronger.

  Next, a fifth embodiment of the present invention will be described with reference to the drawings. FIG. 13 shows an IR cut filter according to a fifth embodiment of the present invention. FIG. 13 (a) is a plan view of the IR cut filter, and FIG. 13 (b) is a sectional view taken along line BB of FIG. 13 (a). It is. The IR cut filter 4 in FIG. 13 has the same basic configuration as the IR cut filter 4 shown in FIG. 2, but is characterized by a method of forming the recess 4c for preventing the adhesive from flowing out. That is, two grooves are formed in the L1 and L2 directions by half dicing around the filter region (indicated by a one-dot chain line) of the IR cut filter 4 made of a glass substrate. A recess 4c is formed. According to the said processing method, the recessed part 4c can be easily formed with respect to a glass substrate.

  The adhesion structure of the IR cut filter with respect to the housing of the solid-state imaging device according to the present invention is not limited to the IR cut filter, and is naturally applicable to any filter adhesion structure.

It is sectional drawing of the solid-state imaging device in 1st Embodiment of this invention. 2A is a plan view of the IR cut filter in FIG. 1, and FIG. 2B is a cross-sectional view taken along the line BB of the IR cut filter shown in FIG. It is an expanded sectional view which shows the adhesion part A of the IR cut filter in FIG. It is sectional drawing of the solid-state imaging device in 2nd Embodiment of this invention. 5A is a plan view of the IR cut filter shown in FIG. 4, and FIG. 5B is a cross-sectional view taken along the line BB of the IR cut filter shown in FIG. It is an expanded sectional view which shows the adhesion part A of the IR cut filter in FIG. It is sectional drawing of the solid-state imaging device in 3rd Embodiment of this invention. Fig.8 (a) is a top view of the resin sheet IR cut filter in FIG. 7, FIG.8 (b) is BB sectional drawing of the resin sheet IR cut filter shown to Fig.8 (a). It is an expanded sectional view which shows the adhesion part A of the resin sheet IR cut filter in FIG. It is sectional drawing of the solid-state imaging device in 4th Embodiment of this invention. Fig.11 (a) is a top view of the resin sheet IR cut filter in FIG. 10, FIG.11 (b) is BB sectional drawing of the resin sheet IR cut filter shown to Fig.11 (a). It is an expanded sectional view which shows the adhesion part A of the resin sheet IR cut filter in FIG. FIG. 13A shows an IR cut filter according to a fifth embodiment of the present invention, FIG. 13A is a plan view of the IR cut filter, and FIG. 13B is a BB of the IR cut filter shown in FIG. It is sectional drawing. It is sectional drawing of the solid-state imaging device in a prior art example. It is an expanded sectional view which shows IR cut filter adhesion part A of FIG. It is a top view of the resin sheet IR cut filter in a prior art example. It is sectional drawing of the resin sheet IR cut filter of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Circuit board 2 Image pick-up element 3 Housing | casing 3a Image pick-up window part 3b Filter holding | maintenance part 3c, 4c, 8c Recessed part 3d, 4d, 8d Opening 4 IR cut filter 5 Holder 6 Lens 7 Adhesive 7a Large diameter part 8 Resin sheet IR cut filter 10, 20, 30, 40, 60 Solid-state imaging device

Claims (8)

  A solid circuit board having a circuit board on which an image sensor is mounted and a housing that covers the circuit board, and a filter holding portion, an IR cut filter bonded to the filter holding portion, and a lens inside the housing. In the imaging device, a solid-state imaging device, wherein a recess or an opening for preventing the adhesive from flowing out is formed in the IR cut filter.   The solid-state imaging device according to claim 1, wherein the concave portion or the opening is formed so as to surround a filter region in the IR cut filter.   The solid-state imaging device according to claim 2, wherein the recess is formed in a ring shape around a filter region in the IR cut filter.   The solid-state imaging device according to claim 2, wherein a plurality of the openings are arranged side by side around a filter region in the IR cut filter.   The solid-state imaging device according to claim 4, wherein an adhesive filled in the opening of the IR cut filter bonded to the filter holding part forms a large-diameter portion outside the opening.   The solid-state imaging device according to claim 1, wherein the IR cut filter is formed of a resin sheet.   The solid-state imaging device according to claim 6, wherein the recess is formed by thermoforming. The solid-state imaging device according to claim 2, wherein the IR cut filter is made of glass, and the concave portion is formed by half dicing.

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