Photodetector

Abstract

To provide a photodetector capable of achieving stable bonding between a wiring substrate and a light receiving element while preventing protrusion of a film-like adhesive member.SOLUTION: A photodetector includes: a wiring substrate 2; a light receiving element 3; at least one connection member 6a, 6b; and a film-like adhesive member 4. A mounting region 5 has a pair of first sides 51a and 51b and a pair of second sides 52a and 52b. The film-like adhesive member 4 is disposed in the mounting region 5. The film-like adhesive member 4 includes a body portion 40 and at least one protruding portion 43,44. The body portion 40 includes a pair of first edges 41a and 41b extending so as to cut out the mounting region 5 in each of the first sides 51a and 51b, and a pair of second edges 42a and 42b extending so as to cut out the mounting region 5 in each of the second sides 52a and 52b. At least one protrusion 43, 44 extends from at least one edge of the edges 41a, 41b, 42a, and 42b.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a light detection device. [Background technology]

[0002] There is known a photodetector that includes a wiring board, a light receiving element mounted on the wiring board, and a connecting member that electrically connects the wiring board and the light receiving element (see, for example, Patent Document 1). For example, in a radiation detection unit used in a CT scanner or the like, a plurality of such photodetectors may be arranged with reduced spacing between them. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-000291 Summary of the Invention [Problem to be solved by the invention]

[0004] In the photodetector described above, a film-like adhesive member may be disposed between the wiring substrate and the light-receiving element. In such a case, if the film-like adhesive member is disposed over the entire area between the wiring substrate and the light-receiving element during manufacturing in order to achieve stable bonding between the wiring substrate and the light-receiving element, the film-like adhesive member may protrude from the area between the wiring substrate and the light-receiving element, making it difficult to arrange multiple photodetectors with reduced spacing between them.

[0005] An object of the present invention is to provide a photodetector that can achieve stable bonding between a wiring board and a light-receiving element while preventing the film-like adhesive member from protruding. [Means for solving the problem]

[0006] The photodetector of the present invention includes: [1] a wiring board; a light-receiving element mounted on the wiring board; a connecting member electrically connecting the wiring board and the light-receiving element; and a film-like adhesive member bonding the wiring board and the light-receiving element, wherein a mounting region where the wiring board and the light-receiving element overlap when viewed from a first direction in which the wiring board and the light-receiving element are aligned has a pair of first sides facing each other in a second direction perpendicular to the first direction and a pair of second sides facing each other in a third direction perpendicular to the first direction and the second direction, and the film-like adhesive member The component is arranged in the mounting area when viewed from the first direction, and the film-like adhesive member includes a main body portion having a pair of first edges extending on each of the pair of first sides so as to cut out the mounting area toward the center of the mounting area, and a pair of second edges extending on each of the pair of second sides so as to cut out the mounting area toward the center of the mounting area, and at least one protrusion extending from at least one edge of each of the pair of first edges and the pair of second edges to the side opposite the center of the mounting area.

[0007] In the photodetector device described in [1] above, the film-shaped adhesive member disposed in the mounting area includes a main body portion that is notched along each side of the mounting area. This makes it difficult for the film-shaped adhesive member to protrude from the mounting area when the wiring board and the light-receiving element are bonded. Furthermore, the main body portion of the film-shaped adhesive member extends to each corner of the mounting area, and the film-shaped adhesive member disposed in the mounting area includes at least one protrusion extending from at least one edge of the main body portion. This makes it easier to maintain a constant distance between the wiring board and the light-receiving element when the wiring board and the light-receiving element are bonded together, resulting in a strong bond between the wiring board and the light-receiving element. Therefore, the photodetector device described in [1] above can achieve stable bonding between the wiring board and the light-receiving element while preventing the film-shaped adhesive member from protruding.

[0008] The photodetector of the present invention may be [2] "the photodetector according to the above [1], wherein at least one protrusion extends from each of the pair of first edges and each of the pair of second edges to the side opposite to the center of the mounting area." The photodetector of [2] can more reliably achieve stable bonding between the wiring board and the light-receiving element.

[0009] The photodetector of the present invention may be [3] "the photodetector according to the above [1] or [2], wherein each of the pair of first edges and each of the pair of second edges extend along a curve concave toward the center of the mounting area." When the wiring board and the light-receiving element are joined, the film-shaped adhesive member is likely to protrude from the center of each side of the mounting area, but the photodetector of [3] can more reliably prevent the film-shaped adhesive member from protruding from the center of each side of the mounting area.

[0010] The photodetector of the present invention may be [4] "the photodetector according to any one of the above [1] to [3], wherein the film-shaped adhesive member includes, as the at least one protrusion, a plurality of protrusions extending from each of the pair of first edges and each of the pair of second edges to the side opposite to the center of the mounting area." The photodetector of [4] can more reliably prevent the film-shaped adhesive member from protruding, while more reliably realizing stable bonding between the wiring board and the light-receiving element.

[0011] The photodetector of the present invention may be [5] "the photodetector according to the above [4], wherein the plurality of protrusions include a first protrusion and a second protrusion having a width greater than that of the first protrusion." According to the photodetector of [5], when the wiring board and the light-receiving element are joined, damage to each protrusion is suppressed when the separator is peeled off from the film-like adhesive member, thereby realizing stable joining between the wiring board and the light-receiving element. Furthermore, suppressing damage to each protrusion improves yield.

[0012] The photodetector of the present invention may be the photodetector described in [6] or [5] above, wherein the plurality of protrusions include a plurality of third protrusions extending from the center of each of the pair of first edges and the pair of second edges toward the opposite side of the center of the mounting area, and a plurality of fourth protrusions extending from both sides of the center of each of the pair of first edges and the pair of second edges toward the opposite side of the center of the mounting area, and each of the third protrusions has a length longer than each of the fourth protrusions. When bonding a wiring board and a light-receiving element, the film-shaped adhesive member is likely to protrude from the center of each side of the mounting area. However, according to the photodetector described in [6], the retraction amount of each edge of the main body portion is increased at the center of each side of the mounting area, thereby more reliably preventing the film-shaped adhesive member from protruding from the center of each side of the mounting area. Furthermore, when bonding a wiring board and a light-receiving element, damage to each protrusion is suppressed when the separator is peeled off from the film-shaped adhesive member, thereby achieving stable bonding between the wiring board and the light-receiving element. Furthermore, by suppressing the occurrence of defects in the protrusions, the yield is improved.

[0013] The photodetector of the present invention may be [7] "the photodetector according to any one of the above [1] to [6], wherein the connecting members are each a plurality of connecting members arranged two-dimensionally." According to the photodetector of [7], even when an area sensor is used as the photodetector, for example, it is possible to prevent the film-like adhesive member from protruding and achieve stable bonding between the wiring board and the photodetector.

[0014] The photodetector of the present invention may be [8] "the photodetector according to the above [7], in which the main body and the at least one protrusion overlap with the plurality of connecting members when viewed from the first direction." According to the photodetector of [8], each connecting member is reinforced by a film-like adhesive member, so that the electrical connection between the wiring board and the light-receiving element by each connecting member can be maintained in a reliable state.

[0015] The photodetector of the present invention may be [9] "the photodetector according to any one of [1] to [8] above, in which the outer edge of the film-shaped adhesive member is located inside the outer edge of the light-receiving element when viewed from the first direction." According to the photodetector of [9], it is possible to more reliably prevent the film-shaped adhesive member from protruding.

[0016] The photodetector of the present invention may be

[10] "the photodetector according to any one of [1] to [9] above, in which the distance between the pair of second sides is greater than the distance between the pair of first sides." According to the photodetector of

[10] , even when a rectangular plate-shaped sensor with its longitudinal direction aligned in the third direction is used as the photodetector, it is possible to prevent the film-like adhesive member from protruding and achieve stable bonding between the wiring board and the photodetector.

[0017] The photodetector of the present invention may be

[11] "the photodetector according to the above

[10] , wherein the main body portion has at least one slit extending from each of the pair of second edges toward the center of the mounting area." According to the photodetector of

[11] , the slits can be sufficiently long at the pair of second edges that are spaced apart more than the pair of first edges, thereby more reliably preventing the film-shaped adhesive member from protruding from each second side of the mounting area. Furthermore, while ensuring a sufficient slit length, damage to the main body portion is suppressed when the separator is peeled off from the film-shaped adhesive member during bonding between the wiring board and the photodetector. Therefore, stable bonding between the wiring board and the photodetector can be achieved.

[0018] The photodetector of the present invention may be

[12] "the photodetector according to any one of the above [1] to

[11] , wherein the film-like adhesive member is an anisotropic conductive film." According to the photodetector of

[12] , the electrical connection between the wiring board and the light-receiving element by the connecting member can be maintained in a reliable state.

[0019] The photodetector of the present invention may be

[13] "the photodetector according to any one of the above [1] to

[12] , further comprising a protective member extending along the outer edge of the region between the wiring board and the photodetector." The photodetector of

[13] can prevent damage such as chipping from occurring in the photodetector. [Effects of the Invention]

[0020] According to the present invention, it is possible to provide a photodetector that can prevent the film-like adhesive member from protruding and achieve stable bonding between the wiring board and the light-receiving element. [Brief explanation of the drawings]

[0021] [Figure 1] 1 is a cross-sectional view of a radiation detector including a photodetector according to an embodiment. [Figure 2] 2 is a bottom view of a portion of the light receiving element shown in FIG. 1. FIG. [Figure 3] FIG. 2 is a plan view of the photodetector shown in FIG. [Figure 4] FIG. 10 is a plan view of a film-shaped adhesive member according to a modified example. DETAILED DESCRIPTION OF THE INVENTION

[0022] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In each drawing, the same or corresponding parts are designated by the same reference numerals, and duplicated explanations will be omitted. [Radiation detector configuration]

[0023] 1, radiation detector 10 includes photodetector 1, scintillator layer 11, a plurality of integrated circuit devices 12, a flexible printed circuit board 13, and a heat sink 14. In radiation detector 10, when radiation (e.g., gamma rays, X-rays, etc.) is incident on scintillator layer 11, scintillation light is generated in scintillator layer 11, and the scintillation light is detected by photodetector 1. Radiation detector 10 is used as a radiation imaging device, for example, in a medical radiation image diagnostic device, a non-destructive testing device, etc.

[0024] The light-detecting device 1 includes a wiring board 2, a light-receiving element 3, a film-like adhesive member 4, a plurality of first connecting members 6a, a plurality of second connecting members 6b (see FIGS. 2 and 3), and a protective member 7. The wiring board 2 has a front surface 2a and a back surface 2b. The light-receiving element 3 has a front surface 3a and a back surface 3b. The light-receiving element 3 is mounted on the front surface 2a of the wiring board 2 with the back surface 3b of the light-receiving element 3 facing the front surface 2a of the wiring board 2. The light-receiving element 3 is a back-illuminated area sensor having a plurality of photodiodes (photoelectric conversion regions) arranged two-dimensionally. Hereinafter, a first direction in which the wiring board and the light-receiving elements are aligned will be referred to as the Z-direction, a second direction perpendicular to the first direction will be referred to as the X-direction, and a third direction perpendicular to the first and second directions will be referred to as the Y-direction.

[0025] The multiple connection members 6a and 6b electrically connect the wiring board 2 and the light-receiving element 3. Specifically, the multiple connection members 6a and 6b electrically and physically connect the multiple pads provided on the wiring board 2 and the multiple electrodes provided on the light-receiving element 3. In this embodiment, each of the connection members 6a and 6b is a bump electrode. The film-shaped adhesive member 4 joins the wiring board 2 and the light-receiving element 3. In this embodiment, the film-shaped adhesive member 4 is an anisotropic conductive film (ACF). The thickness of the film-shaped adhesive member 4 is, for example, 0.03 to 0.08 mm. The protective member 7 extends along the outer edge of the region between the wiring board 2 and the light-receiving element 3. In this embodiment, the protective member 7 surrounds the outer edge of the region between the wiring board 2 and the light-receiving element 3 in a frame shape. The protective member 7 is formed of, for example, an underfill resin agent.

[0026] The scintillator layer 11 is disposed on the surface 3a of the light receiving element 3. When viewed from the Z direction, the scintillator layer 11 is optically separated into photodiodes included in the light receiving element 3. The material of the scintillator layer 11 is, for example, LYSO when gamma rays are to be detected, and is, for example, CsI, GOS when X-rays are to be detected.

[0027] A plurality of integrated circuit devices 12 are mounted on the rear surface 2b of the wiring board 2. Each integrated circuit device 12 is electrically and physically connected to the wiring board 2 by a plurality of bump electrodes 12a. The flexible printed circuit board 13 is electrically and physically connected to the wiring board 2 by a plurality of bump electrodes 13a. In the radiation detector 10, the operation of the light receiving element 3 is controlled by the plurality of integrated circuit devices 12, and the flexible printed circuit board 13 inputs and outputs electrical signals from and to the outside. A heat sink 14 is attached to the rear surface 2b of the wiring board 2 in contact with the plurality of integrated circuit devices 12. The heat sink 14 cools each integrated circuit device 12. [Photodetector configuration]

[0028] 2, the light receiving element 3 includes an n-type semiconductor substrate 30 made of silicon. The thickness of the n-type semiconductor substrate 30 is, for example, 30 to 300 μm. The impurity concentration of the n-type semiconductor substrate 30 is, for example, 1×10 12 ~1×10 15 / cm 3 is.

[0029] A plurality of p-type regions 31 are formed in a portion of the n-type semiconductor substrate 30 along the rear surface 3b. The plurality of p-type regions 31 are arranged two-dimensionally with the X and Y directions being the column and row directions. The plurality of p-type regions 31 form a plurality of pn junction regions with the n-type semiconductor substrate 30. In the light receiving element 3, the plurality of pn junction regions function as a plurality of photodiodes. The width of each p-type region 31 in the Z direction is, for example, 0.05 to 20 μm. The impurity concentration of each p-type region 31 is, for example, 1×10 13 ~1×10 20 / cm 3 is.

[0030] A plurality of high-concentration n-type regions 32 are formed in a portion of the n-type semiconductor substrate 30 along the back surface 3b. When viewed from the Z direction, each high-concentration n-type region 32 extends in a frame shape so as to surround each p-type region 31. The multiple high-concentration n-type regions 32 electrically isolate the multiple photodiodes from each other, thereby suppressing the occurrence of crosstalk between adjacent photodiodes. The width of each high-concentration n-type region 32 in the Z direction is, for example, 0.1 to several tens of μm. The impurity concentration of each high-concentration n-type region 32 is, for example, 1×10 13 ~1×10 20 / cm 3 is.

[0031] A p-type region 33 is formed in a portion of the n-type semiconductor substrate 30 along the back surface 3b. When viewed from the Z direction, the p-type region 33 extends in a lattice pattern so as to pass between adjacent high-concentration n-type regions 32. The p-type region 33 forms a pn junction region with the n-type semiconductor substrate 30. The width of the p-type region 33 in the Z direction is, for example, 0.05 to 20 μm. The impurity concentration of the p-type region 33 is, for example, 1×10 13 ~1×10 20 / cm 3 is.

[0032] A plurality of first connection members 6a are formed on the back surface 3b of the light-receiving element 3. Each first connection member 6a is formed on an anode electrode (not shown) electrically connected to each p-type region 31. Each anode electrode is formed on the back surface of the n-type semiconductor substrate 30 and is located on each p-type region 31. When light is incident on each photodiode from the front surface 3a side, carriers are generated in each photodiode, and a photocurrent generated by the generation of the carriers is output to the wiring board 2 via each first connection member 6a.

[0033] A plurality of second connection members 6b are formed on the back surface 3b of the light-receiving element 3. Each second connection member 6b is formed on a cathode electrode (not shown) electrically connected to the plurality of high-concentration n-type regions 32 and p-type regions 33. The cathode electrode is formed on the back surface of the n-type semiconductor substrate 30 and extends in a lattice pattern so as to cover the plurality of high-concentration n-type regions 32 and p-type regions 33. The plurality of second connection members 6b are formed on a plurality of intersections of the cathode electrode extending in a lattice pattern. However, the plurality of second connection members 6b are not formed on all intersections, but are formed on a plurality of intersections at intervals of a predetermined number of intersections in both the X and Y directions (see FIG. 3). Each second connection member 6b is electrically connected to a ground potential via the wiring substrate 2. [Configuration of film adhesive material]

[0034] As shown in FIG. 3, the film-shaped adhesive member 4 is disposed within the mounting area 5 when viewed from the Z direction. The mounting area 5 is an area where the wiring board 2 and the light-receiving element 3 overlap when viewed from the Z direction. In this embodiment, the mounting area 5 is an area where the back surface 3b of the light-receiving element 3 (specifically, the back surface of the n-type semiconductor substrate 30) and the front surface 2a of the wiring board 2 (i.e., the mounting surface of the wiring board 2) overlap when viewed from the Z direction. In this embodiment, the outer edge of the film-shaped adhesive member 4 is located inside the outer edge of the light-receiving element 3 when viewed from the Z direction. The mounting area 5 has a pair of first sides 51a, 51b and a pair of second sides 52a, 52b. The pair of first sides 51a, 51b face each other in the X direction. The pair of second sides 52a, 52b face each other in the Y direction. The distance between the pair of second sides 52a, 52b is greater than the distance between the pair of first sides 51a, 51b. The length of each of the first sides 51a, 51b is, for example, 30 to 50 mm. The length of each of the second sides 52a, 52b is, for example, 15 to 25 mm. In this embodiment, the mounting area 5 has a rectangular shape with the pair of first sides 51a, 51b as long sides and the pair of second sides 52a, 52b as short sides. In this embodiment, the wiring board 2 and the light receiving element 3 also have substantially the same rectangular shape as the mounting area 5 when viewed from the Z direction. In FIG. 3, the light receiving element 3 is indicated by a two-dot chain line, and the protective member 7 is not shown.

[0035] The film-like adhesive member 4 includes a main body 40. The main body 40 has a pair of first edges 41a, 41b and a pair of second edges 42a, 42b. The first edge 41a extends along a first side 51a so as to cut out the mounting area 5 toward the center 50 of the mounting area 5. That is, the first edge 41a is located inside the first side 51a. The first edge 41b extends along the first side 51b so as to cut out the mounting area 5 toward the center 50 of the mounting area 5. That is, the first edge 41b is located inside the first side 51b. The second edge 42a extends along the second side 52a so as to cut out the mounting area 5 toward the center 50 of the mounting area 5. That is, the second edge 42a is located inside the second side 52a. The second edge 42b extends along the second side 52b so as to cut out the mounting area 5 toward the center 50 of the mounting area 5. That is, the second edge 42b is located inside the second side 52b. In this embodiment, the edges 41a, 41b, 42a, and 42b extend along a curve (for example, a smooth, rounded curve) that is concave toward the center 50 of the mounting area 5. The main body 40 extends to each of the four corners 53 of the mounting area 5. In other words, the main body 40 is not cut out at each of the four corners 53 of the mounting area 5.

[0036] The film-like adhesive member 4 further includes a plurality of first protrusions (protrusions) 43 and a plurality of second protrusions (protrusions) 44. The plurality of protrusions 43, 44 are integrally formed with the main body 40. The second protrusions 44 have a width greater than that of the first protrusions 43. The width of the first protrusions 43 is the width of the first protrusions 43 in a direction perpendicular to the direction in which the first protrusions 43 extend when viewed from the Z direction. The width of the second protrusions 44 is the width of the second protrusions 44 in a direction perpendicular to the direction in which the second protrusions 44 extend when viewed from the Z direction. The width of the first protrusions 43 is, for example, 0.5 to 2 mm. The width of the second protrusions 44 is, for example, 1.5 to 6 mm. A slit opening to the side opposite the main body 40 is formed at the tip end (the end opposite the main body 40) of each second protrusion 44. It is not necessary for the slits opening on the side opposite to the main body 40 to be formed at the tip of each second protrusion 44.

[0037] A plurality of protrusions 43, 44 extend from a first edge 41a of the main body 40 in the X direction to the opposite side of the center 50 of the mounting area 5. A plurality of protrusions 43, 44 extend from a first edge 41b of the main body 40 in the X direction to the opposite side of the center 50 of the mounting area 5. On each of the first edges 41a, 41b, the plurality of protrusions 43, 44 are aligned in the Y direction at predetermined intervals such that multiple (e.g., two) first protrusions 43 are positioned between adjacent second protrusions 44. The predetermined interval is, for example, 0.5 to 2 mm.

[0038] The length of each of the protrusions 43, 44 extending from the first edge 41a (the length of each of the protrusions 43, 44 in the X direction) increases as it approaches the center of the first edge 41a. The length of each of the protrusions 43, 44 may increase continuously by one or may increase stepwise by multiple as it approaches the center of the first edge 41a. The length of each of the protrusions 43, 44 extending from the first edge 41b (the length of each of the protrusions 43, 44 in the X direction) increases as it approaches the center of the first edge 41b. The length of each of the protrusions 43, 44 may increase continuously by one or may increase stepwise by multiple as it approaches the center of the first edge 41b. In this way, each of the multiple protrusions (third protrusions) 43, 44 extending on the opposite side of the center 50 of the mounting area 5 at the center of each first edge 41a, 41b has a length longer than the length of each of the multiple protrusions (fourth protrusions) 43, 44 extending on the opposite side of the center 50 of the mounting area 5 on both sides of the center of each first edge 41a, 41b.

[0039] A plurality of protrusions 43, 44 extend from the second edge 42a of the main body 40 in the Y direction toward the opposite side of the center 50 of the mounting area 5. A plurality of protrusions 43, 44 extend from the second edge 42b of the main body 40 in the Y direction toward the opposite side of the center 50 of the mounting area 5. On each of the second edges 42a, 42b, the plurality of protrusions 43, 44 are arranged in the X direction at predetermined intervals such that a plurality of (e.g., two) first protrusions 43 are located between adjacent second protrusions 44. The predetermined interval is, for example, 0.5 to 2 mm.

[0040] The length of each of the protrusions 43, 44 extending from the second edge 42a (the length of each of the protrusions 43, 44 in the Y direction) increases as the protrusions approach the center of the second edge 42a. The length of each of the protrusions 43, 44 may increase continuously by one or may increase stepwise by multiple steps as the protrusions approach the center of the second edge 42a. The length of each of the protrusions 43, 44 extending from the second edge 42b (the length of each of the protrusions 43, 44 in the Y direction) increases as the protrusions approach the center of the second edge 42b. The length of each of the protrusions 43, 44 may increase continuously by one or may increase stepwise by multiple steps as the protrusions approach the center of the second edge 42b. In this way, each of the multiple protrusions (third protrusions) 43, 44 extending on the opposite side of the center 50 of the mounting area 5 at the center of each second edge 42a, 42b has a length longer than the length of each of the multiple protrusions (fourth protrusions) 43, 44 extending on the opposite side of the center 50 of the mounting area 5 on both sides of the center of each second edge 42a, 42b.

[0041] A pair of slits 40a, 40b are formed in the main body 40. The slit 40a extends from the second edge 42a toward the center 50 of the mounting area 5. In this embodiment, the slit 40a extends from the center of the second edge 42a along the Y direction. As an example, the width of the slit 40a in the X direction is equal to the predetermined distance between the adjacent protrusions 43, 44 along the second edge 42a, and the length of the slit 40a in the Y direction is longer than the length of each of the protrusions 43, 44 extending from the second edge 42a. The slit 40b extends from the second edge 42b toward the center 50 of the mounting area 5. In this embodiment, the slit 40b extends from the center of the second edge 42b along the Y direction. As an example, the width of the slit 40b in the X direction is equal to the predetermined distance between adjacent protrusions 43, 44 along the second edge 42b, and the length of the slit 40b in the Y direction is longer than the length of each of the protrusions 43, 44 extending from the second edge 42b. In this embodiment, the film-like adhesive member 4 has a point-symmetric shape when viewed from the Z direction, with the center 50 of the mounting area 5 as the center of symmetry.

[0042] The main body 40 and the multiple protrusions 43, 44 overlap with the multiple connection members 6a, 6b when viewed from the Z direction. Each first connection member 6a overlaps with the main body 40, the first protrusion 43, or the second protrusion 44 when viewed from the Z direction. Each second connection member 6b overlaps with the main body 40 or the second protrusion 44 when viewed from the Z direction. As described above, the film-shaped adhesive member 4 is an anisotropic conductive film. The anisotropic conductive film includes an insulating resin layer that functions as an adhesive layer and multiple conductive particles dispersed within the insulating resin layer. Therefore, electrical continuity is achieved by the conductive particles contacting each other only in the portions of the film-shaped adhesive member 4 pressed by the connection members 6a, 6b. Therefore, the multiple connection members 6a, 6b are electrically isolated from each other. Note that in FIG. 3, each first connection member 6a is illustrated as a white circle, and each second connection member 6b is illustrated as a black circle. [Method of manufacturing the photodetector]

[0043] A method for manufacturing the above-mentioned photodetector 1 will be described. First, a wiring board 2, a light-receiving element 3 having a plurality of connection members 6a, 6b formed on its rear surface 3b, and a film-like adhesive member 4 having a separator attached to one surface are prepared. The plurality of connection members 6a, 6b are formed on a plurality of electrodes provided on the light-receiving element 3. Next, with the separator attached to one surface of the film-like adhesive member 4, the film-like adhesive member 4 is attached to the front surface 2a of the wiring board 2. Next, the separator is peeled off from the film-like adhesive member 4.

[0044] Next, the light-receiving element 3 is placed on the wiring board 2 via the film-like adhesive member 4 so that the multiple connection members 6a, 6b formed on the back surface 3b of the light-receiving element 3 are positioned on the multiple pads provided on the wiring board 2. Next, the light-receiving element 3 is pressed against the wiring board 2 at a predetermined heating temperature. As a result, the multiple pads provided on the wiring board 2 and the multiple electrodes provided on the light-receiving element 3 are electrically and physically connected by the multiple connection members 6a, 6b, and the wiring board 2 and the light-receiving element 3 are joined by the film-like adhesive member 4. Next, an underfill resin agent is applied along the outer edge of the area between the wiring board 2 and the light-receiving element 3, forming the protective member 7. In this manner, the light-detecting device 1 is obtained.

[0045] The multiple connecting members 6a, 6b may be formed on the front surface 2a of the wiring board 2 when the wiring board 2, the light-receiving element 3, and the film-like adhesive member 4 are prepared. Alternatively, when the wiring board 2, the light-receiving element 3, and the film-like adhesive member 4 are prepared, a portion of each connecting member 6a, 6b may be formed on the front surface 2a of the wiring board 2, and the remaining portion of each connecting member 6a, 6b may be formed on the back surface 3b of the light-receiving element 3. Furthermore, the film-like adhesive member 4 may be attached to the back surface 3b of the light-receiving element 3 with a separator attached to one surface of the film-like adhesive member 4. [Action and effect]

[0046] In the photodetector 1, the film-shaped adhesive member 4 arranged in the mounting area 5 includes a main body portion 40 having a shape cut out along each side 51a, 51b, 52a, and 52b of the mounting area 5. This makes it difficult for the film-shaped adhesive member 4 to protrude from the mounting area 5 when the wiring board 2 and the light-receiving element 3 are bonded together. In addition, the main body portion 40 of the film-shaped adhesive member 4 extends to each corner 53 of the mounting area 5, and further, the film-shaped adhesive member 4 arranged in the mounting area 5 includes a plurality of protrusions 43 and 44 extending from each edge 41a, 41b, 42a, and 42b of the main body portion 40. This makes it easier to maintain a constant distance between the wiring board 2 and the light-receiving element 3 when the wiring board 2 and the light-receiving element 3 are bonded together, resulting in a strong bond between the wiring board 2 and the light-receiving element 3. Even if one of the wiring board 2 and the light-receiving element 3 is tilted relative to the other during bonding, causing uneven pressure to be applied to the wiring board 2 and the light-receiving element 3, the wiring board 2 and the light-receiving element 3 are firmly bonded together. Therefore, the light-detecting device 1 can prevent the film-like adhesive member 4 from protruding and achieve stable bonding between the wiring board 2 and the light-receiving element 3.

[0047] In the photodetector 1, the edges 41a, 41b, 42a, and 42b of the main body 40 extend along curves that are concave toward the center 50 of the mounting area 5. When the wiring board 2 and the light-receiving element 3 are joined, the film-like adhesive member 4 is likely to protrude from the center of each of the sides 51a, 51b, 52a, and 52b of the mounting area 5, but the above configuration more reliably prevents the film-like adhesive member 4 from protruding from the center of each of the sides 51a, 51b, 52a, and 52b of the mounting area 5.

[0048] In the light-detecting device 1, the second protrusions 44 have a width greater than the width of the first protrusions 43 at each edge 41a, 41b, 42a, 42b of the main body 40. This prevents damage to the protrusions 43, 44 when the separator is peeled off from the film-like adhesive member 4 during bonding between the wiring board 2 and the light-receiving element 3, thereby realizing stable bonding between the wiring board 2 and the light-receiving element 3. Furthermore, preventing damage to the protrusions 43, 44 improves yield.

[0049] In the photodetector 1, each of the multiple protrusions 43, 44 extending on the opposite side of the center 50 of the mounting area 5 at the center of each edge 41a, 41b, 42a, 42b of the main body 40 has a length longer than the length of each of the multiple protrusions 43, 44 extending on the opposite side of the center 50 of the mounting area 5 on both sides of the center of each edge 41a, 41b, 42a, 42b of the main body 40. When bonding the wiring board 2 and the light-receiving element 3, the film-like adhesive member 4 is likely to protrude from the center of each side 51a, 51b, 52a, and 52b of the mounting area 5. However, with the above configuration, the edges 41a, 41b, 42a, and 42b of the main body 40 are retracted more greatly at the center of each side 51a, 51b, 52a, and 52b of the mounting area 5, thereby more reliably preventing the film-like adhesive member 4 from protruding from the center of each side 51a, 51b, 52a, and 52b of the mounting area 5. Furthermore, when bonding the wiring board 2 and the light-receiving element 3, damage to the protrusions 43 and 44 is suppressed when the separator is peeled off from the film-like adhesive member 4, thereby achieving stable bonding between the wiring board 2 and the light-receiving element 3. Furthermore, suppressing damage to the protrusions 43 and 44 improves yield.

[0050] In the light-detecting device 1, a plurality of connecting members 6a and 6b are arranged two-dimensionally. That is, even when an area sensor is used as the light-receiving element 3, it is possible to prevent the film-like adhesive member 4 from protruding and achieve stable bonding between the wiring board 2 and the light-receiving element 3.

[0051] In the light-detecting device 1, the main body 40 and the multiple protrusions 43, 44 overlap with the multiple connection members 6a, 6b when viewed from the Z direction. This allows the connection members 6a, 6b to be reinforced by the film-like adhesive member 4, so that the electrical connection between the wiring board 2 and the light-receiving element 3 by the connection members 6a, 6b can be maintained in a reliable state.

[0052] In the photodetector 1, when viewed from the Z direction, the outer edge of the film-shaped adhesive member 4 is located inside the outer edge of the light-receiving element 3. This makes it possible to more reliably prevent the film-shaped adhesive member 4 from protruding.

[0053] In the light-detecting device 1, the distance between the pair of second sides 52a, 52b is greater than the distance between the pair of first sides 51a, 51b. As a result, even when a rectangular plate-shaped sensor with its longitudinal direction aligned in the Y direction is used as the light-receiving element 3, it is possible to prevent the film-like adhesive member 4 from protruding and achieve stable bonding between the wiring board 2 and the light-receiving element 3.

[0054] In the photodetector 1, at a pair of second edges 42a, 42b that are spaced apart more than the space between the pair of first edges 41a, 41b, slits 40a, 40b are formed in the main body 40 so as to extend from the second edges 42a, 42b toward the center 50 of the mounting area 5. This ensures a sufficient length for each slit 40a, 40b, more reliably preventing the film-like adhesive member 4 from protruding from each second edge 52a, 52b of the mounting area 5. Furthermore, while ensuring a sufficient length for each slit 40a, 40b, damage to the main body 40 is suppressed when the separator is peeled off from the film-like adhesive member 4 during bonding between the wiring board 2 and the light-receiving element 3. This allows for stable bonding between the wiring board 2 and the light-receiving element 3.

[0055] In the photodetector 1, the film-like adhesive member 4 is an anisotropic conductive film, which makes it possible to maintain a reliable electrical connection between the wiring board 2 and the light-receiving element 3 via the connection members 6a and 6b.

[0056] In the light-detecting device 1, the protective member 7 extends along the outer edge of the region between the wiring board 2 and the light-receiving element 3. This makes it possible to prevent damage to the light-receiving element 3, such as chipping. [Variations]

[0057] The present invention is not limited to the above-described embodiment. For example, the film-shaped adhesive member 4 may include at least one protrusion (e.g., the first protrusion 43 or the second protrusion 44) extending from at least one of the edges 41a, 41b, 42a, and 42b of the main body 40 toward the opposite side of the center 50 of the mounting area 5. Even in this case, compared to when the film-shaped adhesive member 4 does not include at least one protrusion, for the same reasons as in the above-described embodiment, it is possible to achieve stable bonding between the wiring board 2 and the light-receiving element 3 while preventing the film-shaped adhesive member 4 from protruding. As an example, at least one protrusion may extend from each edge 41a, 41b, 42a, and 42b of the main body 40 toward the opposite side of the center 50 of the mounting area 5.

[0058] In the film-shaped adhesive member 4, the edges 41a, 41b, 42a, and 42b of the main body 40 do not have to extend along a curved line recessed toward the center 50 of the mounting area 5, but rather along a folded line recessed toward the center 50 of the mounting area 5. Furthermore, in the film-shaped adhesive member 4, the main body 40 may be formed with a plurality of slits 40a extending from the second edge 42a toward the center 50 of the mounting area 5. Similarly, in the film-shaped adhesive member 4, the main body 40 may be formed with a plurality of slits 40b extending from the second edge 42b toward the center 50 of the mounting area 5. Alternatively, in the film-shaped adhesive member 4, neither the slits 40a nor the slits 40b may be formed in the main body 40. Furthermore, the film-shaped adhesive member 4 may be an insulating film (NCF: Non-Conductive Film). In this case, it is possible to prevent the film-shaped adhesive member 4 from protruding and achieve stable bonding between the wiring board 2 and the light-receiving element 3.

[0059] In the above-described embodiment, the film-shaped adhesive member 4 is disposed within the mounting area 5 when viewed from the Z direction, and the outer edge of the film-shaped adhesive member 4 is located inside the outer edge of the mounting area 5. However, part of the outer edge of the film-shaped adhesive member 4 may be in contact with the outer edge of the mounting area 5. Furthermore, part of the outer edge of the film-shaped adhesive member 4 may be located outside the outer edge of the mounting area 5. For example, if at least part of the outer edge of at least one of the wiring board 2 and the light-receiving element 3 is located outside the outer edge of the mounting area 5 when viewed from the Z direction, at least part of the outer edge of the film-shaped adhesive member 4 may be located outside the outer edge of the mounting area 5.

[0060] When viewed from the Z direction, the outer edge of the light-receiving element 3 may be located inside the outer edge of the wiring board 2, may be located outside the outer edge of the wiring board 2, or may coincide with the outer edge of the wiring board 2. Furthermore, when viewed from the Z direction, the outer edge of the back surface 3b of the light-receiving element 3 may be located inside the outer edge of the front surface 2a of the wiring board 2, may be located outside the outer edge of the front surface 2a of the wiring board 2, or may coincide with the outer edge of the front surface 2a of the wiring board 2.

[0061] In the above-described embodiment, the length of each of the protrusions 43, 44 increases as it approaches the center of each edge 41a, 41b, 42a, 42b of the main body 40. However, as long as each of the multiple protrusions 43, 44 extending on the opposite side of the center 50 of the mounting area 5 at the center of each edge 41a, 41b, 42a, 42b of the main body 40 has a length longer than each of the multiple protrusions 43, 44 extending on the opposite side of the center 50 of the mounting area 5 on both sides of the center of each edge 41a, 41b, 42a, 42b of the main body 40, for example, a protrusion having a short length may be present at the center of each edge 41a, 41b, 42a, 42b of the main body 40.

[0062] 4, the distance between the pair of second sides 52a, 52b may be equal to the distance between the pair of first sides 51a, 51b in the film-shaped adhesive member 4. In the example shown in FIG. 4, the mounting area 5 has a square shape.

[0063] The light receiving element 3 is not limited to a back-illuminated area sensor, but may be a sensor having a single photodiode. In this case, the number of each of the connecting members 6a, 6b may be one. Furthermore, each of the connecting members 6a, 6b is not limited to a bump electrode, but may be a metal layer or the like. [Explanation of symbols]

[0064] 1...photodetector, 2...wiring board, 3...light-receiving element, 4...film-like adhesive member, 5...mounting area, 6a...first connecting member (connecting member), 6b...second connecting member (connecting member), 40...main body, 40a, 40b...slit, 41a, 41b...first edge, 42a, 42b...second edge, 43...first protrusion (protrusion), 44...second protrusion (protrusion), 50...center, 51a, 51b...first side, 52a, 52b...second side.

Claims

1. A wiring board; a light receiving element mounted on the wiring board; a connecting member electrically connecting the wiring board and the light receiving element; a film-like adhesive member that bonds the wiring board and the light-receiving element, a mounting area where the wiring board and the light receiving element overlap when viewed from a first direction in which the wiring board and the light receiving element are aligned has a pair of first sides facing each other in a second direction perpendicular to the first direction, and a pair of second sides facing each other in a third direction perpendicular to the first direction and the second direction; the film-like adhesive member is disposed in the mounting area when viewed from the first direction, The film-like adhesive member is a main body portion having a pair of first edges extending along each of the pair of first sides so as to cut out the mounting area toward the center of the mounting area, and a pair of second edges extending along each of the pair of second sides so as to cut out the mounting area toward the center of the mounting area; and at least one protrusion extending from at least one edge of each of the pair of first edges and each of the pair of second edges to a side opposite to a center of the mounting area.

2. The light-detecting device according to claim 1 , wherein the at least one protrusion extends from each of the pair of first edges and each of the pair of second edges to a side opposite to a center of the mounting area.

3. The photodetector device according to claim 1 , wherein each of the pair of first edges and each of the pair of second edges extend along a curved line recessed toward a center of the mounting area.

4. 3. The photodetector device according to claim 1, wherein the at least one protrusion of the film-like adhesive member includes a plurality of protrusions extending from each of the pair of first edges and each of the pair of second edges to a side opposite the center of the mounting area.

5. The plurality of protrusions are A first protrusion; The light detection device according to claim 4 , further comprising: a second protrusion having a width greater than a width of the first protrusion.

6. The plurality of protrusions are a plurality of third protrusions extending from the center of each of the pair of first edges and the pair of second edges to the opposite side from the center of the mounting area; a plurality of fourth protrusions extending on both sides of the center of each of the pair of first edges and each of the pair of second edges on the opposite side from the center of the mounting area, The light detection device according to claim 4 , wherein each of the third protrusions has a length longer than a length of each of the fourth protrusions.

7. The photodetector according to claim 1 , wherein the connection member is each of a plurality of connection members arranged two-dimensionally.

8. The light detection device according to claim 7 , wherein the main body and the at least one protrusion overlap with the plurality of connection members when viewed from the first direction.

9. 3. The light detecting device according to claim 1, wherein an outer edge of the film-shaped adhesive member is located inside an outer edge of the light receiving element when viewed from the first direction.

10. The light detection device according to claim 1 , wherein the distance between the pair of second sides is greater than the distance between the pair of first sides.

11. The light-detecting device according to claim 10 , wherein the main body portion has at least one slit formed therein, the slit extending from each of the pair of second edges toward a center of the mounting area.

12. 3. The photodetector according to claim 1, wherein the film-like adhesive member is an anisotropic conductive film.

13. The light-detecting device according to claim 1 , further comprising a protective member extending along an outer edge of an area between the wiring board and the light-receiving element.

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