WO2016166810A1

WO2016166810A1 - Imaging module

Info

Publication number: WO2016166810A1
Application number: PCT/JP2015/061429
Authority: WO
Inventors: 和也前江田
Original assignee: オリンパス株式会社
Priority date: 2015-04-14
Filing date: 2015-04-14
Publication date: 2016-10-20
Also published as: JPWO2016166810A1; JP6542876B2

Abstract

An imaging module 1 is equipped with an imaging element 10 in which a plurality of electrode pads 13 are arranged in a row on an inclined surface 10SS inclined at an acute first angle θ1 relative to a light receiving surface 10SA, a cover glass 30 which is adhered via an adhesive layer 20 in a manner covering the light receiving surface 10SA, each of the aforementioned plurality of electrode pads 13, and a wiring board 40 in which a plurality of junction electrodes 41 to which each of the pads are connected are arranged in a parallel row on a side section of a main surface 40SA and in which an electronic component 69 is mounted upon the aforementioned main surface 40SA, and is further equipped with a holding member 70 which comes into contact with an opposing surface 10SB of the aforementioned imaging element 10 and regulates the front end of the main surface 40SA of the wiring board 40 and the opposing surface 10SB of the imaging element 10 to the aforementioned first angle θ1.

Description

Imaging module

According to the present invention, an imaging element in which a plurality of electrode pads are arranged in a row on an inclined surface which is inclined at an acute angle with respect to a light receiving surface, and a plurality of electrode pads joined in each of the plurality of electrode pads The present invention relates to an imaging module including a wiring board in which first bonding electrodes are arranged in a row at an end.

Since the imaging module manufactured by the wafer level CSP technology is small, for example, it greatly contributes to the diameter reduction of the endoscope.

In the wafer level CSP type imaging module manufacturing method, first, a plurality of light receiving units and a plurality of external electrodes connected to the respective light receiving units are formed on the light receiving surface of the semiconductor wafer. A glass wafer is bonded to the light receiving surface of the semiconductor wafer to produce a bonded wafer. Through-wires are formed which reach from the light-receiving surface of the bonded wafer to the opposing surface.

The light receiving surface of the imaging device of the imaging module obtained by cutting the bonded wafer is covered with a cover glass. Since the light receiving unit is connected to the electrode on the opposite surface through the through wiring, it can transmit and receive an electrical signal.

In Japanese Patent Application Laid-Open No. 2014-75764, an imaging module 101 shown in FIG. 1 is disclosed. The imaging module 101 arranges a plurality of wires in one through trench 110T instead of the plurality of through wires.

The imaging module 101 includes an imaging element 110 to which a cover glass 130 is bonded by an adhesive layer 120, a wiring board 140, and a signal cable 150. In the imaging element 110, a plurality of electrode pads 113 connected to the external electrode 113L of the light receiving surface 110SA are arranged in a row on the inclined wall surface (inclined surface) 110SS of the through trench 110T. The inclined surface 110SS is inclined with respect to the light receiving surface 10SA of the imaging element 110 at a first inclination angle θ1 which is an acute angle.

Each of the plurality of electrode pads 113 is bonded to the plurality of bonding electrodes 141 arranged in a row at the end of the main surface 140SA of the wiring board 140 via the bumps 144. That is, in the wiring board 140, the main surface 140SA is inclined with respect to the facing surface 110SB of the imaging element 110. The signal cable 150 is joined to the other end of the wiring board 140.

Since the imaging module 101 is fixed between the imaging element 110 and the wiring board 140 only at the bonding portion of the bump 144, the mechanical strength is not high. For this reason, the imaging module 101 may be easily damaged when handled, and the yield may not be high.

Unexamined-Japanese-Patent No. 2014-075764

An object of the present invention is to provide an imaging module with high yield.

In the imaging module according to the embodiment of the present invention, the light receiving surface on which the light receiving portion is formed, the facing surface facing the light receiving surface, and the light receiving surface are inclined at a first acute angle. An imaging element having a sloped surface, and a plurality of electrode pads arranged in a row on the sloped surface, and a transparent member adhered through an adhesive layer to cover the light receiving surface of the imaging element Each of the plurality of electrode pads of the imaging device and the plurality of bonding electrodes to which each of the plurality of electrode pads of the imaging device are arranged are arranged in parallel in parallel to the side portion of the main surface. An imaging module including a wiring board having an electronic component mounted on the main surface, wherein the wiring board is in contact with the facing surface of the image pickup element, and a tip end of the main surface of the wiring board Defining the first angle with the opposite surface of the image sensor It is, further comprising a holding member.

According to the present invention, an imaging module with high yield can be provided.

It is a perspective view of the conventional imaging module. It is a sectional view of an imaging module of a 1st embodiment. It is a perspective view of an imaging module of a 1st embodiment. It is a perspective view of the holding member of the imaging module of 1st Embodiment. It is a perspective view of another holding member of an imaging module of a 1st embodiment. It is a perspective view of an imaging module of a 2nd embodiment. It is a perspective view of an imaging module of a modification of a 2nd embodiment. It is a perspective view for demonstrating the manufacturing method of the wiring board of the imaging module of 2nd Embodiment. It is sectional drawing for demonstrating the manufacturing method of the wiring board of the imaging module of 2nd Embodiment. It is sectional drawing of the imaging module of 3rd Embodiment. It is sectional drawing of the imaging module of 4th Embodiment. It is a perspective view of the holding member of the imaging module of 4th Embodiment.

First Embodiment
Hereinafter, an imaging module 1 according to a first embodiment of the present invention will be described with reference to the drawings. The drawings are schematic, and the relationship between the thickness and width of each member, the ratio of the thickness of each member, the number of electrode pads, the arrangement pits, etc. are different from the actual ones. In addition, parts having different dimensional relationships and proportions are included among the drawings. Furthermore, some configurations, for example, a silicon oxide layer on the surface of a silicon substrate, wiring, and the like are not shown.

As shown in FIGS. 2 and 3, the imaging module 1 includes an imaging element 10 made of a silicon substrate, a cover glass 30 which is a transparent member, a wiring board 40, and a signal cable 50.

The imaging device 10 has substantially the same configuration as the imaging device 110 of the conventional imaging module 101 described above. The entire light receiving surface 10SA of the imaging element 10 is covered with a cover glass 30 via an adhesive layer 20.

On the side of the facing surface 10SB of the image pickup device 10, there is a notch 10T whose wall surface is the inclined surface 10SS which is inclined at the first angle θ1 with respect to the light receiving surface 10SA. The first angle θ1 is an acute angle. As described later, the through trench formed by the etching process from the facing surface 10SB side of the bonded wafer becomes the notch 10T by cutting the bonded wafer.

The back surface of the external electrode 12 of the imaging element 10 is exposed at the bottom surface of the notch 10T. A plurality of electrode pads 13 electrically connected to each other through the external electrodes 12 and the solder bumps 44 are arranged in a row on the inclined surface 10SS. For this reason, the electrode pad 13 is electrically connected to the light receiving unit 11. The extended portion of the wiring 13 </ b> L may be the electrode pad 13.

On the other hand, a plurality of bonding electrodes 41 are arranged in a row at the end of the main surface 40SA of the flat flexible wiring board 40, and a bonding electrode 42 is arranged in a row at the other end. The bonding electrode 41 is bonded to the electrode pad 13 via the solder bump 44. On the other hand, the bonding electrode 42 is bonded to the conducting wire 51 of the signal cable 50. The bonding electrode 41 and the bonding electrode 42 are electrically connected via the electronic component 69 mounted on the main surface 40SA or a wire (not shown).

In addition, in order to improve joining reliability, the joining location of the 1st joining electrode 42 and the electrode pad 13 may be sealed by sealing resin. However, it may not be easy to ensure sufficient mechanical strength with a sealing resin that fixes only the bonding points.

On the other hand, in the imaging module 1, the distal end portion of the main surface 40SA of the wiring board 40 and the opposing surface 10SB of the imaging element 10 are defined at a first angle θ1 while in contact with the opposing surface 10SB of the imaging element 10 The holding member 70 is provided.

As shown in FIG. 4A, the holding member 70 has a rectangular central plate 70L, and angle defining portions 70W1 and 70W2 disposed upright on both sides of the central plate 70L. The angle defining units 70W1 and 70W2 are triangles in plan view in which an angle formed by the first side L1 and the second side L2 is a first angle θ1.

The holding member 70 has the two angle defining portions 70W1 and 70W2 at the ends of both long sides, but may have only one of them. Further, hereinafter, each of the two angle defining portions 70W1 and 70W2 is referred to as an angle defining portion 70W.

The central plate 70 </ b> L of the holding member 70 is bonded to the facing surface 10 </ b> SB of the imaging device 10. The first side L1 of the angle defining portion 70W abuts on the main surface 40SA of the wiring board 40 and is bonded with an adhesive (not shown).

The angle defining portion 70W is disposed on the outer peripheral portion of the central plate 70L. Therefore, even if the angle defining portion 70W is present, the electronic component 69 can be mounted on the main surface 40SA of the wiring board 40. That is, although the imaging module 1 includes the angle defining unit 70W as a holding member, the angle defining unit 70W and the electronic component 69 overlap when viewed from the side.

A resin member 65 is injected between the holding member 70 and the wiring board 40 and hardened. That is, the relative position of the wiring board 40 and the imaging device 10 is fixed by the resin member 65. The resin member 65 is, for example, a thermosetting epoxy resin which is liquid in an uncured state.

The surface of the electronic component 69 mounted on the wiring board 40 is covered with the resin member 65 and protected.

Unlike the angle defining portion of the holding member 70A of the imaging module 1A illustrated in FIG. 4B, the angle defining portion 70W illustrated in FIG. 4A is strictly trapezoidal. However, if the angle between the first side L1 and the second side L2 is the first angle θ1, the angle defining portion 70W may be substantially triangular.

The central plate 70L and the angle defining portion 70W may be manufactured as an integral body, or the angle defining portion 70W may be bonded to the central plate 70L. Further, the central plate 70L and the angle defining portion 70W of the holding member 70 made of metal, resin, or ceramic may be made of different materials.

If the length of the second side L2 is 20% or more of the length of the imaging device 10, the holding member 70 can stably define the relative angle between the imaging device 10 and the wiring board 40. Further, if the length of the second side L2 is 80% or less of the length of the imaging device 10, the signal cable 50 connected to the wiring board 40 can be placed in the projection plane of the imaging device 10 as described later. It can be arranged.

In the imaging module 1, the imaging element 10 and the wiring board 40 are held by the holding member 70 with the relative angle defined at the first angle θ1. For this reason, the imaging module 1 has high mechanical strength between the imaging element 10 and the wiring board 40, is less likely to be damaged by handling, and has a sufficiently high final yield.

In the imaging module 1, the wiring board 40 and the signal cable 50 located on the rear side (opposite side of the cover glass) of the imaging device 10 overlap the imaging device 10 when the imaging device 10 is viewed in plan from the thickness direction. That is, the whole is located in the projection plane of the imaging device 10. In particular, in the case where the wiring portion 40L of the wiring board 40 is flexible, even if the length of the wiring board 40 is long, the whole can be disposed within the projection plane of the imaging device 10 by being curved and deformed. The imaging module 1 has a small diameter because the wiring board 40 and the signal cable 50 do not protrude outside the outer shape of the imaging device 10.

Second Embodiment
Next, an imaging module 1B according to a modification of the second embodiment will be described. In addition, since the imaging module 1B is similar to the imaging module 1 and has the same effect, the same code | symbol is attached | subjected to the component of the same function, and description is abbreviate | omitted.

As shown in FIG. 5, in the imaging module 1B, the wiring board 40B has a function of a holding unit. That is, in the wiring board 40B, angle defining portions 40W1 and 40W2 upright with respect to the main surface 40SA are extended at the long side of the rectangular wiring portion 40L.

In the wiring board 40B, a wiring layer is disposed on a base at least the surface of which is nonconductive. The angle defining portion 40W is preferably made of the same material as that of the base, particularly, a high thermal conductivity material having a thermal conductivity of 10 W / (mK) or more.

For example, the substrate may be coated with a non-conductive material such as copper (398 W / (mK)) or aluminum (236 W / (mK)), alumina (20 W / (mK)), carbonized Ceramics such as silicon (200 W / (mK)), silicon nitride (27 W / (mK)) and aluminum nitride (170 W / (mK)) may be used.

The imaging module 1 </ b> B is easy to manufacture because the process of bonding the holding portion to the wiring board is unnecessary. Further, the imaging module 1B in which a part of the base made of the high thermal conductivity material is bonded to the imaging device 10 can efficiently transfer the heat generated by the imaging device 10, so it has high reliability.

Modification of Second Embodiment
Next, an imaging module 1C of a modification of the second embodiment will be described. In addition, since the imaging module 1C is similar to the imaging module 1B and has the same effect, the same code | symbol is attached | subjected to the component of the same function, and description is abbreviate | omitted.

As shown in FIG. 6A, in the wiring board 40C of the imaging module 1C, extending portions extending from the long side of the rectangular wiring portion 40L, which are erected with respect to the main surface 40SA, are holding members 40W1 and 40W2. It is. The holding member 40W is an angle defining member of a triangle in plan view, in which the angle formed by the first side L1 and the second side L2 is a first angle θ1.

The wiring board 40C is a flexible wiring board having, for example, a polyimide as a base. The base of the wiring portion 40L and the holding member 40W may be a non-flexible substrate made of glass epoxy resin or the like, but a portion to be bent for bending to be described later, that is, the wiring portion 40L and the holding member 40W Only the border area with must be flexible.

In order to accommodate the wiring board 40C in the projection plane of the imaging device 10, it is preferable that the wiring board 40C be a flexible substrate. Electronic components 69 such as chip capacitors and chip inductors are mounted on the main surface 40SA of the wiring portion 40L. Note that the electronic component may be mounted also on the main surface 40SB facing the main surface 40SA.

As shown in FIGS. 6B and 6C, the holding members 40W1 and 40W2 are bent so as to stand upright on the main surface 40SA of the wiring board 40C. When the flat wiring board 40 is bent, it becomes a three-dimensional solid. The width of the wiring board 40 may be equal to or less than the width of the imaging device 10, including the bent holding member 40W.

As shown in FIG. 6C, the holding members 40W1 and 40W2 are preferably fixed in an upright state by the curable resin 45. For example, an ultraviolet curable resin is used as the curable resin 45.

The imaging module 1C is three-dimensionally formed by bending the extended portion of the general flat wiring board 40C, and therefore is easier to manufacture than the imaging module 1B.

Third Embodiment
Next, an imaging module 1D according to a modification of the third embodiment will be described. In addition, since the imaging module 1B is similar to the imaging module 1 and has the same effect, the same code | symbol is attached | subjected to the component of the same function, and description is abbreviate | omitted.

As shown in FIG. 7, in the image pickup device 10D of the image pickup module 1D, as in the case of the image pickup device 110 of the conventional image pickup module 101 described above, through trenches 10TA having inclined surfaces 10SS and 10ST are formed. There is. That is, the cutting position of the bonded wafer is different from that of the imaging device 10. However, the basic configuration of the imaging device 10D is the same as that of the imaging device 10.

Further, in the wiring board 40D of the imaging module 1D, the bonding electrodes provided in a row on the end face are the flying leads 41A. The flying leads 41A (referred to as outer leads in the lead frame) are made of conductor wiring from which the insulating base of the wiring board 40A is selectively removed.

The flying leads 41A can be easily bent, and the solder bumps 44 can be directly heated without passing through the base of the wiring board 40D.

Therefore, the imaging module 1D is easier to manufacture than the imaging module 1 and the like.

Furthermore, in the imaging module 1D, the

electronic components

69A and 69B mounted on the main surface 40SA of the wiring board 40D form a first angle θ1 between the tip of the main surface 40SA of the wiring board 40D and the opposing surface 10SB of the imaging element 10D. Have the function of the holding member defined in That is, the

electronic components

69A and 69B are in contact with the facing surface 10SB of the imaging element 10D. In addition, at least one electronic component may be in contact with the facing surface 10SB, but when the plurality of

electronic components

69A and 69B are in contact, angle definition is easier.

In the

electronic components

69A and 69B, the main surface 40SA of the wiring board 40D and the opposing surface 10SB of the imaging device 10D have a first angle θ1 when the corners thereof abut on the opposing surface 10SB of the imaging device 10D. The placement position is determined in consideration of the height.

The imaging module 1D is easy to manufacture because it does not require a dedicated holding member for angle definition.

In the imaging module 1D, the resin member 65 is injected into the space between the imaging element 10D and the wiring board 40D and is cured. The electronic component 69C is also mounted on the main surface 40SB of the wiring board 40D.

Although the

electronic components

69A and 69B define angles, the imaging element 10D and the wiring board 40D are not fixed. The relative positions of the imaging element 10D and the wiring board 40D are fixed by the resin member 65.

The imaging module 1D fixed by the resin member 65 has a mechanical strength higher than that of the imaging module 1 and the like.

Fourth Embodiment
Next, an imaging module 1E according to a modification of the fourth embodiment will be described. In addition, since the imaging module 1E is similar to the imaging module 1 etc. and has the same effect, the same code | symbol is attached | subjected to the component of the same function, and description is abbreviate | omitted.

As shown in FIGS. 8 and 9, in the imaging module 1E, a block 70E having an inclined surface inclined at a first inclination angle θ1 with respect to the bottom surface corresponds to the main surface 40SA of the wiring board 40E and the imaging device 10D. It is a holding | maintenance part which is prescribed | regulated so that opposing surface 10SB may become 1st angle (theta) 1. FIG. The bottom surface 70SB of the block 70E is bonded to the wiring board 40E and the imaging device 10D by an adhesive (not shown).

The block 70E is preferably made of a high thermal conductivity material having a thermal conductivity of 10 W / (mK) or more in order to efficiently transfer the heat generated by the imaging device 10D.

In the block 70E, a concave portion 70H in accordance with the size of the electronic component 69A is formed on the inclined surface 70SA. Therefore, the electronic component 69A can be disposed on the main surface 40SA of the wiring board 40E.

Electronic parts

69B and 69C are also mounted on the main surface 40SB of the wiring board 40E.

That is, although the imaging module 1E includes the block 70E as a holding member, the holding member and the electronic component overlap when viewed from the side.

The present invention is not limited to the above-described embodiment, modifications, and the like, and various changes, modifications, combinations, and the like can be made without departing from the scope of the present invention.

1, 1A to 1E: imaging module 10: imaging element 20: adhesive layer 30: cover glass 40: wiring board 40L: wiring portion 40W: angle defining portion (holding member)
41: bonding electrode 41A: flying lead 42: bonding electrode 44: solder bump 45: hardening resin 65: resin member 69: electronic component 70: holding member 70E: block 70H: recess 70L: central plate 70W: angle defining portion

Claims

The light receiving surface includes a light receiving surface on which a light receiving portion is formed, an opposing surface facing the light receiving surface, and an inclined surface which is inclined at a first acute angle with respect to the light receiving surface. An imaging element in which a plurality of electrode pads are arranged in a row on the surface;
A transparent member adhered via an adhesive layer so as to cover the light receiving surface of the imaging device; and each of the plurality of electrode pads of the imaging device disposed on the opposite surface side of the imaging device; An imaging module comprising: a wiring board in which a plurality of bonding electrodes to which each is bonded are arranged in parallel in a side edge portion of a main surface, and an electronic component is surface-mounted on the main surface. ,
It further comprises a holding member in contact with the opposite surface of the image sensor, and defining the tip of the main surface of the wiring board and the opposite surface of the image sensor at the first angle. An imaging module characterized by
The imaging module according to claim 1, wherein the holding member and the electronic component overlap when viewed from the side.
The imaging module according to claim 2, wherein the holding member includes an angle defining portion of a triangle of the first angle formed by the first side and the second side.
The imaging module according to claim 3, wherein the holding member includes a rectangular central plate and the angle defining portion which is upright with respect to the central plate.
The imaging module according to claim 3, wherein the angle defining portion is an extended portion of the wiring board which is upright with respect to the main surface.
The imaging module according to claim 5, wherein the extending portion is made of a base material of the wiring board having a thermal conductivity of 10 W / (mK) or more.
The imaging module according to claim 5, wherein the extended portion is bent from the wiring board.
The imaging module according to claim 3, wherein the angle defining unit is the electronic component surface-mounted on the wiring board.
The angle defining portion is a block having an inclined surface which is inclined at the first inclination angle with respect to the bottom surface,
The imaging module according to claim 3, wherein the block includes a hole into which at least a part of the electronic component is inserted.
10. At least one part of the surface of the said electronic component is covered by the resin member arrange | positioned between the said image pick-up element and the said wiring board, The any one of the Claims 1-9 characterized by the above-mentioned. The imaging module described in.