Radiation detector and method for manufacturing the same

Abstract

To improve the productivity of a radiation detector.SOLUTION: A radiation detector 1 comprises: a photoelectric conversion element array 7; a scintillator layer 8 for converting radiation into light; a rein frame 9 formed on the photoelectric conversion element array 7; and a protective film 13 covering the scintillator layer 8. A groove 30 continuous to an outer edge 13a of the protective film 13 is formed in the resin frame 9, the groove 30 including an overlapping region 31 that includes a first groove end 32 and a second groove end 33 that partly overlap in a direction that crosses the extension direction of the groove 30.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a radiation detector and a method for manufacturing a radiation detector. [Background technology]

[0002] Patent Documents 1, 2, and 3 disclose radiation detectors. The radiation detectors disclosed in these documents have a scintillator layer that converts radiation into light, and a photodetector panel that detects the light. The photodetector panel has a light receiving section in which a plurality of light receiving elements are arranged, and a plurality of bonding pads that are provided around the light receiving section and electrically connected to the light receiving section. A resin frame that surrounds the light receiving section is formed between the light receiving section and the bonding pads. The scintillator layer is covered with a moisture-resistant protective film. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2015-96823 A [Patent Document 2] JP 2016-205916 A [Patent Document 3] U.S. Patent Publication No. 2012 / 0288688 Summary of the Invention [Problem to be solved by the invention]

[0004] In the methods of manufacturing a radiation detector disclosed in Patent Documents 1 and 2, a scintillator layer is formed on a light detection panel, and then a resin frame is formed. Next, a protective film is formed. The protective film is formed on the scintillator layer and on the bonding pads, and it is sufficient that the protective film covers the scintillator layer. Therefore, a part of the protective film that covers the bonding pads is removed. Specifically, in order to cut the protective film, the protective film is cut by irradiating it with laser light on the resin frame.

[0005] When the protective film is irradiated with laser light, the laser light needs to have energy equal to or greater than a threshold value in order to reliably cut the protective film. On the other hand, if the energy of the laser light is too strong, the laser light may cut the protective film and the resin frame, causing damage to the light detection panel. Furthermore, even if the laser light does not reach the light detection panel, if the groove formed in the resin frame becomes deep, this may cause unintended defects. Moreover, since the heights of the protective film and the resin frame are not necessarily constant, the above-mentioned defects may occur even if the energy of the laser light is kept constant.

[0006] In other words, even if the laser light irradiation conditions are kept constant, the radiation detectors manufactured will not satisfy the predetermined performance. Therefore, in this field, there has been a demand for a technique that can improve productivity in the manufacture of radiation detectors by reducing the occurrence of defective products.

[0007] SUMMARY OF THE PRESENT DISCLOSURE In view of the above, an object of the present invention is to provide a radiation detector and a method for manufacturing a radiation detector that are capable of improving productivity. [Means for solving the problem]

[0008] A radiation detector according to one embodiment of the present invention includes a photodetection panel having a light receiving section including a plurality of photoelectric conversion elements arranged one-dimensionally or two-dimensionally, and a plurality of bonding pads electrically connected to the photoelectric conversion elements and arranged outside the light receiving section, a scintillator layer laminated on the photodetection panel so as to cover the light receiving section and converts radiation into light, a resin frame formed on the photodetection panel so as to pass between the scintillator layer and the bonding pads and surround the scintillator layer while being spaced from the scintillator layer and the bonding pads when viewed from the lamination direction of the scintillator layer, and a scintillator protective film covering the scintillator layer and having an outer edge located on the resin frame. A groove is formed in the resin frame, which is continuous with the outer edge of the scintillator protective film, and the groove has an overlapping region including a first groove end and a second groove end that partially overlap in a direction intersecting the extension direction of the groove.

[0009] The groove of the resin frame of the radiation detector is continuous with the outer edge of the scintillator protective film, and is formed with the formation of the outer edge of the scintillator protective film by irradiation with laser light. The groove being formed in the resin frame means that the scintillator protective film formed on the resin frame is reliably cut. The groove includes an overlapping region including the first groove end and the second groove end. Due to the partial overlap between the first groove end and the second groove end, the depth of the groove does not become too deep in the overlapping region. As a result, it is possible to prevent the laser light from penetrating not only the scintillator protective film but also the resin frame. In other words, the scintillator protective film is reliably cut, and the surface of the light detection panel on which the resin frame is provided is not damaged by the irradiation of the laser light. Therefore, the occurrence of defective products is suppressed, and productivity can be improved.

[0010] The radiation detector according to one embodiment may further include a coating resin that covers an outer edge of the scintillator protective film. With this configuration, peeling of the scintillator protective film can be suppressed.

[0011] In one embodiment of the radiation detector, the coating resin may further cover the resin frame, and the coating resin may have material properties that allow it to remain on the resin frame such that an edge of a contact surface between the coating resin and the resin frame is formed on the resin frame. With this configuration, the coating resin does not reach the surface of the light detection panel and the bonding pads located outside the resin frame. Therefore, the surface of the light detection panel and the bonding pads can be kept clean.

[0012] In one embodiment of the radiation detector, the center of the resin frame may be higher than both edge portions of the resin frame, and the groove may be positioned on the resin frame toward the bonding pad side. With this configuration, the coating resin can reliably cover the outer edge of the scintillator protective film.

[0013] In one aspect of the radiation detector, the resin frame may have a width of not less than 700 micrometers and not more than 1000 micrometers. With this configuration, the radiation detector can be made smaller.

[0014] In one aspect of the radiation detector, the resin frame may have a height of not less than 100 micrometers and not more than 300 micrometers. With this configuration, the radiation detector can be made compact.

[0015] In one embodiment of the radiation detector, the light detection panel may be rectangular in shape, the resin frame may have four sides surrounding the scintillator layer, and the overlapping region may be provided on any of the four sides. With this configuration, peeling of the scintillator protective film can be further suppressed.

[0016] A method for manufacturing a radiation detector according to another embodiment of the present invention includes the steps of preparing a light-receiving section including a plurality of photoelectric conversion elements arranged one-dimensionally or two-dimensionally, and a light-detecting panel having a plurality of bonding pads electrically connected to the photoelectric conversion elements and arranged outside the light-receiving section, laminating a scintillator layer that converts radiation into light on the light-detecting panel so as to cover the light-receiving section, arranging a panel protection section on the light-detecting panel so as to surround the scintillator layer when viewed from the lamination direction of the scintillator layer, and covering the entire surface of the light-detecting panel on the side where the scintillator layer is laminated and the surface of the panel protection section. The method includes the steps of forming a scintillator protective film, cutting the scintillator protective film by irradiating laser light along the panel protective portion so that the scintillator protective film is cut, and removing an outer portion of the scintillator protective film. In the step of cutting the scintillator protective film, the laser light is irradiated so that an outer edge of the scintillator protective film is formed due to the cutting of the scintillator protective film, and a groove that is continuous with the outer edge of the scintillator protective film is formed in the panel protective portion, and the groove has an overlapping region that includes a first groove end and a second groove end that partially overlap in a direction intersecting the extension direction of the groove.

[0017] In the above-mentioned method for manufacturing a radiation detector, in the step of cutting the scintillator protective film, an outer edge of the scintillator protective film is formed and a groove is formed in the panel protective part. The groove being formed in the panel protective part means that the scintillator protective film formed on the panel protective part is reliably cut. The groove includes an overlapping region including a first groove end and a second groove end. Due to the partial overlap between the first groove end and the second groove end, the depth of the groove does not become too deep in the overlapping region. As a result, it is possible to prevent the laser light from penetrating not only the scintillator protective film but also the panel protective part. In other words, the scintillator protective film is reliably cut, and the surface of the light detection panel on which the panel protective part is provided is not damaged by the irradiation of the laser light. Therefore, the occurrence of defective products is suppressed, and the productivity can be improved.

[0018] In another embodiment of the method for manufacturing a radiation detector, the light detection panel has a rectangular shape, the panel protection part has four sides surrounding the scintillator layer, and in the step of cutting the scintillator protection film, an overlapping region may be provided on any of the four sides. This step can further prevent peeling of the scintillator protection film.

[0019] In another embodiment of the method for manufacturing a radiation detector, the step of cutting the scintillator protective film may include the steps of setting at least one of the positions of four corners formed by the four sides as a reference position, and irradiating each of the four sides with laser light based on the reference position. This step makes it possible to precisely control the position to which the laser light is irradiated.

[0020] In another embodiment of the method for manufacturing a radiation detector, the panel protection part may be a resin frame, and in the step of arranging the panel protection part, the resin frame may be arranged on the light detection panel so as to be spaced apart from the scintillator layer and the bonding pad, pass between the scintillator layer and the bonding pad, and surround the scintillator layer. According to this step, a radiation detector having a resin frame can be manufactured.

[0021] In another embodiment of the method for manufacturing a radiation detector, in the step of arranging the panel protection part, the resin frame may be formed so that a center portion of the resin frame is higher than both edge portions of the resin frame, and in the step of cutting the scintillator protection film, the laser light may be irradiated to a position on the resin frame that is biased toward the bonding pad side. According to this step, the outer edge of the scintillator protection film can be reliably covered with the coating resin.

[0022] In another embodiment of the method for manufacturing a radiation detector, the panel protection part is a masking member, and in the step of arranging the panel protection part, the masking member may be arranged on the light detection panel so as to cover the bonding pad and the region between the scintillator layer and the bonding pad, and in the step of forming the scintillator protective film, the scintillator protective film may be formed on the entire surface of the light detection panel on the side on which the scintillator layer is laminated and on the surface of the masking member. This step makes it possible to manufacture a radiation detector without a resin frame. In other words, it becomes possible to reduce the distance between the scintillator layer and the bonding pad, thereby making it possible to further miniaturize the radiation detector.

[0023] In another embodiment of the method for manufacturing a radiation detector, the method may further include a step of removing the masking member after the step of removing the outer portion of the scintillator protective film. This step makes it possible to suitably manufacture a radiation detector that does not include a resin frame.

[0024] In another embodiment of the method for manufacturing a radiation detector, after the step of removing the outer portion of the scintillator protective film, a step of forming a coating resin that covers the outer edge of the scintillator protective film can be further included. This step can further suppress peeling of the outer edge of the scintillator protective film. Effect of the Invention

[0025] According to the present invention, a radiation detector and a method for manufacturing a radiation detector that can improve productivity are provided. [Brief description of the drawings]

[0026] [Figure 1] FIG. 1 is a plan view of the radiation detector according to the first embodiment. [Diagram 2] FIG. 2 is a cross-sectional view taken along line II-II in FIG. [Diagram 3] FIG. 3 is an enlarged plan view showing the vicinity of a corner of the radiation detector of FIG. [Figure 4] FIG. 4 is a plan view showing the resin frame of FIG. 1 and grooves provided in the resin frame. [Diagram 5] FIG. 5 is an enlarged plan view of the overlapping region of FIG. [Figure 6] FIG. 6 is a perspective view showing a cross section taken along line VI-VI in FIG. [Figure 7] Fig. 7(a) is a cross-sectional view showing a resin frame of a comparative example, and Fig. 7(b) is a cross-sectional view showing a resin frame of the embodiment. [Figure 8] Fig. 8(a) is a cross-sectional view showing a state before a scintillator layer is formed, and Fig. 8(b) is a cross-sectional view showing a state after a scintillator layer is formed. [Figure 9] Fig. 9(a) is a cross-sectional view showing a state after a resin frame has been formed, and Fig. 9(b) is a cross-sectional view showing a state after a first organic film has been formed. [Figure 10] Fig. 10(a) is a cross-sectional view showing a state after an inorganic film has been formed, and Fig. 10(b) is a cross-sectional view showing a state after a second organic film has been formed. [Figure 11] FIG. 11 is a cross-sectional view showing a processing process using a laser beam. [Figure 12] FIG. 12 is a diagram for specifically explaining the processing using laser light. [Figure 13] Fig. 13(a) is a diagram for explaining processing along the front irradiation line, and Fig. 13(b) is a diagram for explaining processing along the first irradiation line. [Figure 14] Fig. 14(a) is a diagram for explaining the processing along the second irradiation line, and Fig. 14(b) is a diagram for explaining the processing along the third irradiation line. [Figure 15] Fig. 15(a) is a diagram for explaining processing along the fourth irradiation line, and Fig. 15(b) is a diagram for explaining processing along the subsequent irradiation line. [Figure 16] FIG. 16 is a diagram for explaining the processing along the release line. [Figure 17] Fig. 17(a) is a cross-sectional view showing a state where a part of the protective film has been removed, and Fig. 17(b) is a cross-sectional view showing a state where a coating resin has been formed. [Figure 18] Fig. 18(a) is a cross-sectional view showing a resin frame of a comparative example, and Fig. 18(b) is a cross-sectional view showing a resin frame of the embodiment. [Figure 19] FIG. 19 is a plan view of the radiation detector according to the second embodiment. [Figure 20] FIG. 20 is a cross-sectional view taken along the line XX-XX in FIG. [Figure 21] FIG. 21 is a first perspective view of the radiation detector of FIG. [Figure 22] FIG. 22 is a second perspective view of the radiation detector of FIG. [Diagram 23] Fig. 23(a) is a cross-sectional view showing a state before a scintillator layer is formed, and Fig. 23(b) is a cross-sectional view showing a state after a scintillator layer is formed. [Figure 24] Fig. 24(a) is a cross-sectional view showing the state after the masking member is placed, and Fig. 24(b) is a cross-sectional view showing the state after the first organic film is formed. [Diagram 25] Fig. 25(a) is a cross-sectional view showing the state after the inorganic film has been formed, and Fig. 25(b) is a cross-sectional view showing the state after the second organic film has been formed. [Figure 26] FIG. 26 is a cross-sectional view showing a processing process using a laser beam. [Figure 27] FIG. 27 is a plan view showing the resin frame of FIG. 19 and grooves provided in the resin frame. [Figure 28]Fig. 28(a) is a cross-sectional view showing a process of removing the masking material, and Fig. 28(b) is a cross-sectional view showing the state after the masking material has been removed. [Figure 29] FIG. 29 is a cross-sectional view showing a radiation detector which is a modified example of the second embodiment. [Diagram 30] Fig. 30(a) is a graph showing a schematic diagram of the time history of the energy received by the irradiated object, and Fig. 30(b) is a graph showing a schematic diagram of the time history of the velocity of the laser optical head. [Diagram 31] FIG. 31 is a graph showing a schematic time history of the energy received by the irradiated object. [Diagram 32] Fig. 32(a) is a graph showing an example of the time history of the speed of a laser light head. Fig. 32(b) is a graph showing an example of the time history of the energy of a laser light emitted from the laser light head. Fig. 32(c) is a graph showing an example of the time history of the focal position of a laser light emitted from the laser light head. [Diagram 33] Fig. 33(a) is a graph showing an example of the time history of the speed of the laser optical head, and Fig. 33(b) is a diagram showing a schematic diagram of the positional relationship between the laser optical head, the protective film, and the resin frame. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0027] Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings. In the description of the drawings, the same elements are given the same reference numerals, and duplicated explanations will be omitted.

[0028] The configuration of a radiation detector 1 according to this embodiment will be described with reference to Figures 1 and 2. As shown in Figures 1 and 2, the radiation detector 1 includes a photoelectric conversion element array 7 (light detection panel), a scintillator layer 8, a resin frame 9, a protective film 13 (scintillator protective film), and a coating resin 14 (coating resin). The photoelectric conversion element array 7 includes a substrate 2, a light receiving section 3, signal lines 4, bonding pads 5, and a passivation film 6. The protective film 13 includes a first organic film 10, an inorganic film 11 (metal film), and a second organic film 12.

[0029] The light receiving section 3 includes a plurality of photoelectric conversion elements 3a arranged two-dimensionally in a rectangular region in the center of an insulating substrate 2 (e.g., a glass substrate). The photoelectric conversion elements 3a are composed of amorphous silicon photodiodes (PDs), thin film transistors (TFTs), etc. Each of the photoelectric conversion elements 3a in each row or column in the light receiving section 3 is electrically connected to a bonding pad 5 for extracting a signal to an external circuit (not shown) by a signal line 4 for signal readout.

[0030] A plurality of bonding pads 5 are arranged at predetermined intervals along two adjacent sides (the upper side and the right side in FIG. 1) of the outer edge of the substrate 2. The bonding pads 5 are electrically connected to the corresponding photoelectric conversion elements 3a via the signal lines 4. An insulating passivation film 6 is formed on the photoelectric conversion elements 3a and the signal lines 4. The passivation film 6 may be made of, for example, silicon nitride or silicon oxide. The bonding pads 5 are exposed for connection to an external circuit.

[0031] A columnar scintillator 8a that converts X-rays (radiation) into light is laminated on the photoelectric conversion element array 7 so as to cover the light receiving section 3. The scintillator layer 8 is formed of a plurality of scintillators 8a laminated in a substantially rectangular region (region surrounded by a dashed line in FIG. 1) including the light receiving section 3 in the photoelectric conversion element array 7. Various materials can be used for the scintillator 8a. For example, Tl-doped CsI, which has good luminous efficiency, can be used for the scintillator 8a.

[0032] The peripheral portion 8b of the scintillator layer 8 has a gradient shape in which the height gradually decreases toward the outside of the scintillator layer 8. That is, in the peripheral portion 8b, the scintillator 8a formed on the outside of the scintillator layer 8 has a lower height. Here, the peripheral portion 8b is a region (region outside the effective screen) below which the light receiving portion 3 is not formed. Alternatively, the peripheral portion 8b is a region that is less affected in X-ray image generation. Therefore, by providing the peripheral portion 8b with such a gradient shape, it is possible to limit the region on the scintillator layer 8 that is adversely affected by the laser light during manufacturing. Here, the gradient angle (angle θ) of the peripheral portion 8b is defined. The angle θ is the angle that a straight line connecting the height positions of the scintillators 8a formed in the peripheral portion 8b from the inside to the outside of the scintillator layer 8 makes with the upper surface of the substrate 2. This angle θ is included in the range of 20 degrees to 80 degrees.

[0033] The resin frame 9 is formed on the photoelectric conversion element array 7 so as to pass between the scintillator layer 8 and the bonding pads 5 and surround the scintillator layer 8 when viewed from the stacking direction A of the scintillator layer 8. The corners of the resin frame 9 are shaped like outwardly convex arcs (so-called R-shapes). The resin frame 9 is, for example, a silicone resin.

[0034] The resin frame 9 is formed so that the center is higher than both edge portions. The height d1 of the resin frame 9 is lower than the height d of the scintillator layer 8. This makes it possible to reduce the size of the resin frame 9 and suppress adverse effects of laser light on the scintillator layer 8 during manufacturing. Here, the height d1 of the resin frame 9 is the distance between the top surface position of the photoelectric conversion element array 7 and the apex position of the resin frame 9. The height d of the scintillator layer 8 is the maximum height of the scintillator 8a included in the scintillator layer 8.

[0035] From the viewpoint of miniaturizing the radiation detector 1, it is preferable that the resin frame 9 be as small as possible. More specifically, the height d1 of the resin frame 9 is 100 μm or more. Moreover, the height d1 of the resin frame 9 is 300 μm or less. Furthermore, the width d2 of the resin frame 9 is 700 μm or more. The width d2 of the resin frame 9 is 1000 μm or less. Here, the width d2 of the resin frame 9 is the width between the inner edge E1 of the resin frame 9 and the outer edge E2 of the resin frame 9. The inner edge E1 is the edge on the scintillator layer 8 side. The outer edge E2 is the edge on the bonding pad 5 side.

[0036] Moreover, the distance between the inner edge E1 of the resin frame 9 and the outer edge E3 of the scintillator layer 8 is a first distance D1. Moreover, the distance between the outer edge E2 of the resin frame 9 and the outer edge E4 of the photoelectric conversion element array 7 is a second distance D2. The first distance D1 is shorter than the second distance D2. From the viewpoint of suppressing adverse effects of the laser light on the bonding pad 5 during manufacturing and ensuring the effective area of ​​the scintillator layer 8, it is preferable that the ratio of the second distance D2 to the first distance D1 is 5 or more. More specifically, it is preferable that the first distance D1 is 1 mm or less. It is preferable that the second distance D2 is 5 mm or more. This is for the following reasons.

[0037] If there is no gap between the outer edge E3 of the scintillator layer 8 and the inner edge E1 of the resin frame 9, the effective area of ​​the scintillator layer 8 can be maximized. However, considering the adverse effects of laser light on the scintillator layer 8 during manufacturing and the possibility of a slight failure in the process of forming the resin frame 9 (for example, forming the resin frame 9 on the scintillator layer 8), it is preferable to ensure that the first distance D1 is in the range of 1 mm or less. Furthermore, by setting the second distance D2 to 5 mm or more, a sufficient distance can be ensured between the resin frame 9 and the bonding pad 5, taking into account the adverse effects of laser light on the bonding pad 5 during manufacturing.

[0038] The scintillator layer 8 is covered with a protective film 13. The protective film 13 has a first organic film 10, an inorganic film 11, and a second organic film 12. These films are laminated in this order from the scintillator layer 8 side. The first organic film 10, the inorganic film 11, and the second organic film 12 are all permeable to X-rays (radiation). The first organic film 10, the inorganic film 11, and the second organic film 12 block water vapor. Specifically, the first organic film 10 and the second organic film 12 can be made of polyparaxylylene resin, polyparachloroxylylene, or the like. The inorganic film 11 can be transparent, opaque, or reflective to light. The inorganic film 11 can be made of, for example, an oxide film of Si, Ti, Cr, or the like, or a metal film of gold, silver, aluminum (Al), or the like. For example, the inorganic film 11 using a metal film that reflects light can prevent leakage of fluorescence generated in the scintillator 8a. As a result, the detection sensitivity of the radiation detector 1 is improved. In this embodiment, an example will be described in which Al, which is easy to mold, is used as the inorganic film 11. Al itself is easily corroded in air. However, the inorganic film 11 is sandwiched between the first organic film 10 and the second organic film 12. Therefore, the inorganic film 11 using Al is protected from corrosion.

[0039] The protective film 13 is formed by, for example, a CVD method. Therefore, immediately after the protective film 13 is formed, the protective film 13 covers the entire surface of the photoelectric conversion element array 7. Therefore, in order to expose the bonding pads 5, the protective film 13 is cut at a position inside the bonding pads 5 of the photoelectric conversion element array 7. Then, the protective film 13 outside the cutting position is removed. As described later, the protective film 13 is cut (processed) by a laser beam near the outside from the center of the resin frame 9, and the outer edge 13a of the protective film 13 is fixed by the resin frame 9. This makes it possible to prevent the protective film 13 from peeling off from the outer edge 13a. Here, for example, a carbon dioxide laser (CO2 laser) and an ultrashort pulse (nanosecond or picosecond) semiconductor laser can be used to cut the protective film 13. By using a carbon dioxide laser, the protective film 13 can be cut in one scan (short time). As a result, productivity is improved. Note that adverse effects on the photoelectric conversion element array 7, the bonding pads 5, the scintillator layer 8, etc. are thermal damage, for example, when a carbon dioxide gas laser or an ultrashort pulse laser is used.

[0040] An outer edge 13a of the protective film 13 is located on the resin frame 9. The outer edge 13a is coated together with the resin frame 9 by a coating resin 14 arranged along the resin frame 9. The coating resin 14 may be a resin having good adhesion to the protective film 13 and the resin frame 9. For example, an acrylic adhesive or the like may be used for the coating resin 14. Note that the coating resin 14 may be a silicone resin similar to the resin frame 9. Alternatively, the resin frame 9 may be an acrylic resin similar to the coating resin 14.

[0041] Next, the corners of the resin frame 9 and the protective film 13 will be described with reference to Fig. 3. In Fig. 3, in order to make it easier to understand the state of the corners of the resin frame 9 and the protective film 13, part of the coating resin 14 is not shown.

[0042] Although the details will be described later, in the manufacturing process of the radiation detector 1, the protective film 13 on the resin frame 9 is irradiated with laser light, and the portion of the protective film 13 irradiated with the laser light is cut. Here, since the protective film 13 is very thin, a part of the resin frame 9 is also cut by the laser light of the carbon dioxide laser. As a result, a groove 30 (corresponding region) is formed near the center of the resin frame 9. The outer edge 13a of the protective film 13 and the outer edge 13a of the protective film 13 in the resin frame 9 are in a state processed by the laser light. The groove 30 is also in a state processed by the laser light. Here, the depth (height) d3 of the groove 30 is 1 / 3 or less of the height d1 of the resin frame 9. As a result, the adverse effect of the laser light on the photoelectric conversion element array 7 located below the resin frame 9 is suppressed.

[0043] As shown in FIG. 3, the shape of the outer edge 13a of the protective film 13 and the groove 30 processed by the laser light is a substantially rectangular ring shape having an outwardly convex arc-shaped corner (see region B shown in FIG. 3) when viewed from the stacking direction A of the scintillator layer 8. In addition, the outer edge 13a of the protective film 13 and the surface of the groove 30 are finely wavy when viewed from the stacking direction A. That is, the outer edge 13a of the protective film 13 and the surface of the groove 30 are different from a flat cut surface by a blade such as a cutter. The outer edge 13a of the protective film 13 and the surface of the groove 30 have a fine uneven shape. This increases the contact area between the outer edge 13a of the protective film 13 and the coating resin 14. Therefore, the adhesion between the outer edge 13a of the protective film 13 and the coating resin 14 can be made stronger. The contact area between the groove 30 and the coating resin 14 also increases. Therefore, the adhesion between the groove 30 and the coating resin 14 can also be made stronger.

[0044] Next, the groove 30 will be described in more detail with reference to FIG. 4, FIG. 5, FIG. 6, and FIG. 7. As shown in FIG. 4, the resin frame 9 surrounds the light receiving unit 3. The shape of the resin frame 9 is rectangular in plan view. Therefore, the resin frame 9 includes a first side portion 9a, a second side portion 9b, a third side portion 9c, and a fourth side portion 9d. The groove 30 is formed in the resin frame 9. In other words, the groove 30 extends along the extending direction of the resin frame 9. That is, the shape of the groove 30 is also rectangular in plan view. The groove 30 includes an overlapping region 31. In this embodiment, the overlapping region 31 is formed in the first side portion 9a. Note that the overlapping region 31 may be formed in any one of the second side portion 9b, the third side portion 9c, and the fourth side portion 9d. In other words, the overlapping region 31 is not formed in a corner portion.

[0045] Fig. 5 is an enlarged view of the vicinity of the overlap region 31 in Fig. 4. Fig. 6 is a perspective view showing a cross section taken along the line VI-VI in Fig. 5. In Fig. 6, the coating resin 14 is virtually shown by a two-dot chain line. The overlap region 31 includes two first groove ends 32 and a second groove end 33. The first groove end 32 is formed in the vicinity of the timing when the laser light irradiation is started. The second groove end 33 is formed in the vicinity of the timing when the laser light irradiation is stopped.

[0046] The first groove end 32 is formed on the inside of the second groove end 33. "Inside" means the side of the scintillator layer 8 with respect to the resin frame 9. "Outside" means the side of the bonding pad 5 with respect to the resin frame 9. That is, the second groove end 33 is formed on the outside of the first groove end 32. The first groove end 32 partially overlaps with the second groove end 33 in the width direction of the groove 30. Specifically, an outer part 32a of the first groove end 32 overlaps with an inner part 33a of the second groove end 33. Then, the width W31 of the overlapping part is larger than the width W32 of the first groove end 32. Similarly, the width W31 of the overlapping part is larger than the width W33 of the second groove end 33. On the other hand, the width W31 of the overlapping portion is smaller by the overlapping length than the sum of the width W32 of the first groove end 32 and the width W33 of the second groove end 33. In this overlapping portion, the first groove end 32 is connected to the second groove end 33.

[0047] The overlapping region 31 is biased toward the bonding pad 5 on the resin frame 9. For example, a distance W1 from an outer side of the second groove end 33 to an edge of the resin frame 9 on the bonding pad 5 side is shorter than a distance W2 from an inner side of the first groove end 32 to an edge of the resin frame 9 on the scintillator layer 8 side. In addition, an inner region 9A and an outer region 9B are defined in the resin frame 9 by dividing the resin frame 9 in half in the width direction. In this definition, the entire second groove end 33 is formed in the outer region 9B. A part of the first groove end 32 is formed in the outer region 9B, and another part is formed in the inner region 9A.

[0048] As shown in FIG. 7, in the overlapping region 31, two first groove ends 32 and two second groove ends 33 are arranged in the width direction of the resin frame 9. In the overlapping region 31, a part of the first groove end 32 overlaps a part of the second groove end 33 in the width direction. More specifically, the inner periphery side of the first groove end 32 located in the overlapping region 31 overlaps with the outer periphery side of the second groove end 33 located in the overlapping region 31. That is, in the overlapping region 31, the first groove end 32 is connected to the second groove end 33. The depth of the first groove end 32 is defined as the distance from the point where the center line CL intersects with the surface of the resin frame 9 to the deepest part of the first groove end 32. The depth of the second groove end 33 is defined in the same manner. In this way, it can be said that the depth of the first groove end 32 is approximately the same as the depth of the second groove end 33.

[0049] For example, when the first groove end 32 and the second groove end 33 completely overlap, the laser light forming the second groove end 33 is irradiated to the deepest part of the first groove end 32 (see FIG. 7(a)). As a result, the groove depth in the overlap region 31 becomes twice as deep as the depth in the first groove end 32, assuming that the laser light irradiation conditions are the same.

[0050] However, in this embodiment, the first groove end 32 and the second groove end 33 are shifted so as to run parallel to each other. Therefore, as shown in Fig. 7(b), the laser light forming the second groove end 33 is irradiated to the outside of the first groove end 32, that is, to the surface of the unprocessed resin frame 9. In this case, the depth of the groove in the overlap region 31 is not twice the depth of the groove formed by one irradiation, as in the case where the first groove end 32 and the second groove end 33 completely overlap each other.

[0051] Next, the operation of the radiation detector 1 according to this embodiment will be described. X-rays (radiation) incident from the incident surface side pass through the protective film 13 and reach the scintillator 8a. The X-rays are absorbed by the scintillator 8a. The scintillator 8a emits light proportional to the amount of absorbed X-rays. Of the emitted light, light traveling in the opposite direction to the incident direction of the X-rays is reflected by the inorganic film 11. For this reason, almost all of the light generated by the scintillator 8a is incident on the photoelectric conversion element 3a through the passivation film 6. Each photoelectric conversion element 3a generates an electric signal corresponding to the amount of incident light by photoelectric conversion. The electric signal is accumulated for a certain period of time. The amount of this light corresponds to the amount of incident X-rays. In other words, the electric signal accumulated in each photoelectric conversion element 3a corresponds to the amount of incident X-rays. Therefore, an image signal corresponding to an X-ray image is obtained by this electric signal. The image signals stored in the photoelectric conversion elements 3a are sequentially read out from the bonding pads 5 via the signal lines 4 and then transferred to the outside. The transferred image signals are processed by a predetermined processing circuit to display an X-ray image.

[0052] <Radiation detector manufacturing method> Next, a method for manufacturing the radiation detector 1 according to this embodiment will be described with reference to Figs. 8 to 18. First, as shown in Fig. 8(a), a photoelectric conversion element array 7 is prepared (step S1). Then, as shown in Fig. 8(b), a scintillator layer 8 is formed (laminated) (step S2). Specifically, in a region covering the light receiving section 3 on the photoelectric conversion element array 7, columnar crystals of CsI doped with Tl are grown by, for example, a vapor deposition method. The thickness of the CsI columnar crystals is, for example, about 600 µm.

[0053] Next, as shown in FIG. 9(a), a resin frame 9 is formed on the photoelectric conversion element array 7 (step S3). Specifically, when viewed from the stacking direction A of the scintillator layer 8, the resin frame 9 is formed so as to pass between the scintillator layer 8 and the bonding pad 5 and surround the scintillator layer 8. More specifically, the resin frame 9 is formed at a position where the first distance D1 is 1 mm or less and the second distance D2 is 5 mm or more. For example, an automatic XY coating device can be used to form the resin frame 9. Hereinafter, for convenience of explanation, the photoelectric conversion element array 7 on which the scintillator layer 8 and the resin frame 9 are formed will be simply referred to as a "substrate".

[0054] In step S3, in addition to the resin frame 9, a masking member as shown in the second embodiment (see FIG. 24(a)) may be placed. The masking member is placed in the area outside the resin frame 9 so as to cover the bonding pads 5. The masking member protects the surfaces of the bonding pads 5. When a masking member is placed, the masking member is removed together with the protective film 13 in step S6, which will be described later, for removing the outer portion of the protective film 13.

[0055] Next, as shown in FIG. 9(b), a first organic film 10 is formed (step S4a). CsI forming the scintillator layer 8 is highly hygroscopic. Therefore, if the scintillator layer 8 is left exposed, it will absorb water vapor in the air. As a result, the scintillator layer 8 will dissolve. Therefore, the entire surface of the substrate is covered with polyparaxylylene by, for example, a CVD method. The thickness of the polyparaxylylene may be 5 μm or more and 25 μm or less.

[0056] Next, as shown in FIG. 10(a), an inorganic film (metal film) 11 is formed (step S4b). Specifically, an Al film having a thickness of 0.2 μm is laminated by deposition on the surface of the first organic film 10 on the side of the incident surface on which radiation is incident. The incident surface on which radiation is incident is the surface on which the scintillator layer 8 of the radiation detector 1 is formed. Next, as shown in FIG. 10(b), a second organic film 12 is formed (step S4c). Specifically, the entire surface of the substrate on which the inorganic film 11 is formed is again covered with polyparaxylylene by CVD. The thickness of the polyparaxylylene may be 5 μm to 25 μm. The second organic film 12 prevents deterioration of the inorganic film 11 due to corrosion. Through the above processes (steps S4a, S4b, and S4c), a protective film 13 is formed. The portion of the protective film 13 outside the approximate center of the resin frame 9 is removed by a subsequent process. The portion of the protective film 13 outside the approximate center portion of the resin frame 9 is the portion covering the bonding pads 5. Therefore, the first organic film 10 and the second organic film 12 do not need to be formed on the side surface of the photoelectric conversion element array 7. In addition, the first organic film 10 and the second organic film 12 do not need to be formed on the surface of the photoelectric conversion element array 7 opposite to the side on which the scintillator layer 8 is laminated.

[0057] 11, laser light L is applied along the resin frame 9 to cut the protective film 13 (step S5). Specifically, a laser light head (not shown) that applies the laser light L is moved relative to a stage (not shown) on which the entire substrate having the protective film 13 formed on its surface is placed, so that the laser light L scans the resin frame 9 in a single stroke.

[0058] Hereinafter, step S5 of cutting protective film 13 will be described in further detail with reference to FIGS.

[0059] First, as shown in FIG. 12, a first reference line C1, a second reference line C2, a third reference line C3, and a fourth reference line C4 are defined. In order to define the first reference line C1, the second reference line C2, the third reference line C3, and the fourth reference line C4, several reference points are defined (step S5s). For example, an image is obtained by capturing an image of the resin frame 9 with a camera. For example, seven reference points are specified from the image. These reference points may overlap with the center line of the resin frame 9. The reference points may also be set at the corners.

[0060] Next, the laser light is irradiated (step S5r). This step S5r includes a step of defining a scanning line and a step of performing an operation along the scanning line. The scanning line includes several elements. Specifically, the scanning line includes a front irradiation line RS, a first irradiation line R1, a second irradiation line R2, a third irradiation line R3, a fourth irradiation line R4, a rear irradiation line RE, and a release line RL. The step of performing an operation along the scanning line also includes a plurality of elements according to these elements. In the following description, an operation in which the definition of the elements of the scanning line and the operation along the elements are repeated is exemplified. That is, the front irradiation line RS is defined, and an operation along the front irradiation line RS is immediately performed. Next, the first irradiation line R1 is defined, and an operation along the first irradiation line R1 is immediately performed. Similarly, the definition and operation are performed for the second irradiation line R2, the third irradiation line R3, the fourth irradiation line R4, the rear irradiation line RE, and the release line RL.

[0061] In addition, the definition of the scanning line may be performed in a lump, and then the operation along the scanning line may be performed in a lump. The definition of the scanning line and the operation along the scanning line may be performed in parallel. For example, the first scanning line may be defined while the operation along the front irradiation line is being performed.

[0062] First, the front irradiation line RS is defined (step S5a: see FIG. 13(a)). The front irradiation line RS is a section from the starting point PSs to the starting point P1s of the first irradiation line R1. The starting point PSs is spaced a predetermined distance from the first reference line C1 and a predetermined distance from the fourth reference line C4. As an example, the predetermined distances are each 70 μm. The front irradiation line RS is parallel to the first reference line C1 and spaced a predetermined distance (e.g., 70 μm) from the first reference line C1.

[0063] Next, an operation is performed along the pre-irradiation line RS (step S5b). First, the laser light head is moved to the starting point PSs. Next, the laser light head starts moving along the pre-irradiation line RS. The speed of the laser light head is, for example, 6000 mm / min. At this time, the laser light head does not emit laser light. The laser light head starts irradiating the laser light at least after the starting point PSs of the pre-irradiation line RS and up to the starting point P1s of the first irradiation line R1. For example, the laser light head may start irradiating the laser light from the starting point P1s of the first irradiation line R1.

[0064] Next, the first irradiation line R1 is defined (step S5c: see FIG. 13(b)). The first irradiation line R1 includes a first irradiation side R1a and a first irradiation corner R1b. The first irradiation side R1a is continuous with the front irradiation line RS. That is, the first irradiation side R1a is parallel to the first reference line C1 and is spaced from the first reference line C1 by a predetermined distance (e.g., 70 μm). The first irradiation corner R1b connects the first irradiation side R1a and a second irradiation side R2a, which will be described later. The first irradiation corner R1b corresponds to the hypotenuse of a right-angled isosceles triangle with a side length of 0.4 mm at the corner between the first irradiation side R1a and the second irradiation side R2a.

[0065] Next, an operation is performed along the first irradiation line R1 (step S5d). The speed of the laser light head is, for example, 6000 mm / min.

[0066] Next, the second irradiation line R2 is defined (step S5e: see FIG. 14(a)). The second irradiation line R2 includes a second irradiation side R2a and a second irradiation corner R2b. The second irradiation side R2a is continuous with the first irradiation corner R1b. The second irradiation side R2a is parallel to the second reference line C2 and is spaced from the second reference line C2 by a predetermined distance (e.g., 70 μm). The second irradiation corner R2b connects the second irradiation side R2a and a third irradiation side R3a, which will be described later. The second irradiation corner R2b corresponds to the hypotenuse of a right-angled isosceles triangle with a side length of 0.4 mm at the corner between the second irradiation side R2a and the third irradiation side R3a.

[0067] Next, an operation is performed along the second irradiation line R2 (step S5f). The speed of the laser light head is, for example, 6000 mm / min.

[0068] Next, the third irradiation line R3 is defined (step S5g: see FIG. 14(b)). The third irradiation line R3 includes a third irradiation side R3a and a third irradiation corner R3b. The third irradiation side R3a is continuous with the second irradiation corner R2b. The third irradiation side R3a is parallel to the third reference line C3 and is spaced from the third reference line C3 by a predetermined distance (e.g., 70 μm). The third irradiation corner R3b connects the third irradiation side R3a and a fourth irradiation side R4a, which will be described later. The third irradiation corner R3b corresponds to the hypotenuse of a right-angled isosceles triangle with a side length of 0.4 mm at the corner between the third irradiation side R3a and the fourth irradiation side R4a.

[0069] Next, an operation along the third irradiation line R3 is performed (step S5h). The speed of the laser light head is, for example, 6000 mm / min.

[0070] Next, the fourth irradiation line R4 is defined (step S5i: see FIG. 15(a)). The fourth irradiation line R4 includes a fourth irradiation side R4a and a fourth irradiation corner R4b. The fourth irradiation side R4a is continuous with the third irradiation corner R3b. The fourth irradiation side R4a is parallel to the fourth reference line C4 and is spaced from the fourth reference line C4 by a predetermined distance (for example, 70 μm). The fourth irradiation corner R4b connects the fourth irradiation side R4a with the rear irradiation line RE described later. The fourth irradiation corner R4b corresponds to the hypotenuse of a right-angled isosceles triangle with a side length of 0.4 mm at the corner between the fourth irradiation side R4a and the rear irradiation line RE. Here, the fourth irradiation corner R4b intersects with the front irradiation line RS. The end point of the fourth irradiation corner R4b is set at a position spaced a predetermined distance (for example, 100 μm) outward from the front irradiation line RS.

[0071] Next, an operation is performed along the fourth irradiation line R4 (step S5j). The speed of the laser light head is, for example, 6000 mm / min.

[0072] Next, the rear irradiation line RE is defined (step S5k: see FIG. 15(b)). The rear irradiation line RE is parallel to the front irradiation line RS and the first irradiation side R1a. In the direction parallel to the first reference line C1, the rear irradiation line RE overlaps with the front irradiation line RS. Therefore, the rear irradiation line RE extends parallel to the front irradiation line RS along the first reference line C1.

[0073] Next, an operation is performed along the post-irradiation line RE (step S5m). The speed of the laser light head is, for example, 6000 mm / min.

[0074] Then, the release line RL is defined (step S5n: see FIG. 16). The release line RL is parallel to the first illuminated side R1a. The end point of the release line RL is set on the second reference line C2. That is, the release line RL includes a portion that overlaps with the first illuminated side R1a and a portion that overlaps with the first illuminated corner R1b along the first reference line C1.

[0075] Next, an operation is performed along the release line RL (step S5p). The speed of the laser light head is, for example, 15000 mm / min. That is, the speed of the laser light head on the release line RL is faster than the speed of the laser light head on the first, second, third and fourth irradiation lines R1, R2, R3 and R4. This operation shortens the irradiation time of the laser light per unit length. That is, the irradiation energy given to the resin frame 9 gradually decreases. Furthermore, in the operation along the release line RL, the distance from the resin frame 9 to the laser light head is gradually increased. This operation moves the focal position of the laser light upward. That is, the irradiation energy given to the resin frame 9 gradually decreases. These operations allow the depth of the groove to be gradually shallowed.

[0076] By carrying out the above step S5, the protective film 13 is cut.

[0077] Next, as shown in FIG. 17(a), the bonding pad 5 is exposed by removing the portion of the protective film 13 outside the cut portion caused by the laser light L (step S6). The portion outside the cut portion includes the portion opposite the incident surface. Next, as shown in FIG. 17(b), an uncured resin material is coated along the resin frame 9 (step S7). The uncured resin material is provided so as to cover the outer edge 13a of the protective film 13 and the resin frame 9. The uncured resin material is, for example, an ultraviolet-curable acrylic resin. Then, the uncured resin material is irradiated with ultraviolet light. As a result, the resin material is cured, and a coating resin 14 is formed.

[0078] The resin material is supplied from the syringe needle to the top of the resin frame 9. In other words, the resin material is supplied to the highest position of the resin frame 9. That is, the syringe needle is positioned such that the center line of the syringe needle overlaps with the center line of the resin frame 9.

[0079] The resin material supplied onto the resin frame 9 flows along the surface of the resin frame 9 toward the substrate 2. At this time, the extent to which the resin material flows on the surface of the resin frame 9 is determined by the material properties of the resin material. Examples of such material properties include viscosity and thixotropy. A resin material with high viscosity is less likely to flow. Thixotropy is a property in which the viscosity changes over time, and can be said to be an indicator of how easily the shape can be maintained. When a material with high thixotropy continues to receive shear stress, the viscosity decreases and approaches a liquid. On the other hand, when the material remains stationary, the viscosity gradually increases and approaches a solid. The resin material used in this embodiment has both relatively high viscosity and thixotropy. Therefore, after being supplied to the surface of the resin frame 9, the resin material is relatively less likely to flow along the surface.

[0080] For example, in the resin frame 109 of the comparative example shown in FIG. 18(a), a groove 130 is formed in the center of the resin frame 109. Then, the uncured resin material 14S covers the overlapping portion H1 on the surface of the protective film 13. The end of the overlapping portion H1 includes the outer edge 13a of the protective film 13. The outer edge 13a is an uneven surface as described above. Therefore, the deformation of the resin material with high thixotropy is hindered by the unevenness, and it is difficult for the resin material to flow downward. As a result, it is sometimes difficult to sufficiently cover the outer edge 13a with the coating resin 14.

[0081] On the other hand, in the resin frame 9 of this embodiment shown in FIG. 18(b), the groove 30 is formed on the outer side (the bonding pad 5 side) of the resin frame 9. According to this configuration, the outer edge 13a of the protective film 13 is also formed on the outer side (the bonding pad 5 side). In other words, compared to the comparative example, the overlapping portion H2 of the protective film 13 formed on the resin frame 9 is increased. As a result, when the uncured resin material 14S is supplied onto the resin frame 9, the resin material 14S can cover a sufficient area including the outer edge 13a. Furthermore, since the scintillator layer 8 side of the resin material 14S is sufficiently separated from the outer edge 13a, it is less susceptible to the unevenness of the outer edge 13a. Therefore, the uncured resin material 14S can flow downward to further expand the overlapping area. In other words, since the position of the groove 30 is formed offset from the center of the resin frame 9, the outer edge 13a can be sufficiently covered with the coating resin 14.

[0082] Furthermore, the groove 30 of the embodiment has another advantageous effect in forming the coating resin 14. Refer to FIG. 18(a) again. In the resin frame 109 of the comparative example, the groove 130 is deep as a result of irradiating the same portion with the laser light twice. In other words, the ratio of the opening width to the depth of the groove 130 is large. That is, the groove 130 is a deep narrow groove. The resin material 14S having high viscosity and thixotropy is difficult to enter into such a groove 130. As a result, the resin material 14S may not be filled entirely in the groove 130, and a sealed cavity 130S may be formed at the bottom of the groove 130. If such a sealed cavity 130S exists, for example, when heat is applied to the substrate 2, the air inside expands. This expansion of the air may have an adverse effect on the protective film 13 and the scintillator layer 8.

[0083] On the other hand, the groove 30 of the embodiment shown in Fig. 18(b) has a smaller ratio of the opening width to the depth of the groove 30 than the comparative example. This is because multiple irradiation of the same location in the resin frame 9 with laser light is avoided. With such a groove 30, even a resin material 14S having high viscosity and thixotropy is satisfactorily filled into the entire groove 30. As a result, the formation of a cavity 130S is prevented, and adverse effects on the protective film 13 and the scintillator layer 8 that may occur during heat treatment can be eliminated.

[0084] Furthermore, the protective film 13 adheres closely to the photoelectric conversion element array 7 via the resin frame 9 even without providing the coating resin 14. However, by forming the coating resin 14, the protective film 13 including the first organic film 10 is sandwiched and fixed between the resin frame 9 and the coating resin 14. As a result, the adhesion of the protective film 13 to the photoelectric conversion element array 7 is further improved. Therefore, the scintillator 8a is sealed by the protective film 13. As a result, it is possible to reliably prevent moisture from entering the scintillator 8a, and therefore it is possible to prevent a decrease in the resolution of the elements due to moisture deterioration of the scintillator 8a.

[0085] <Action and effect> The radiation detector 1 includes a photoelectric conversion element array 7 having a light receiving section 3 including a plurality of photoelectric conversion elements 3a arranged one-dimensionally or two-dimensionally, and a plurality of bonding pads 5 electrically connected to the photoelectric conversion elements 3a and arranged outside the light receiving section 3, a scintillator layer 8 that is stacked on the photoelectric conversion element array 7 so as to cover the light receiving section 3 and converts radiation into light, a resin frame 9 formed on the photoelectric conversion element array 7 so as to pass between the scintillator layer 8 and the bonding pads 5 and surround the scintillator layer 8, spaced apart from the scintillator layer 8 and the bonding pads 5, when viewed from the stacking direction A of the scintillator layer 8, and a protective film 13 that covers the scintillator layer 8 and has an outer edge 13a located on the resin frame 9. A groove 30 that is continuous with the outer edge 13a of the protective film 13 is formed in the resin frame 9, and the groove 30 has an overlapping region 31 including a first groove end 32 and a second groove end 33 that partially overlap in a direction intersecting the extension direction of the groove 30.

[0086] The groove 30 in the resin frame 9 of the radiation detector 1 is continuous with the outer edge 13a of the protective film 13, and is formed when the outer edge 13a of the protective film 13 is formed by irradiating the laser light. The groove 30 being formed in the resin frame 9 means that the protective film 13 formed on the resin frame 9 is reliably cut. The groove 30 includes an overlapping region 31 including a first groove end 32 and a second groove end 33. Due to the partial overlap between the first groove end 32 and the second groove end 33, the depth of the groove 30 does not become too deep in the overlapping region 31. As a result, it is possible to prevent the laser light from penetrating not only the protective film 13 but also the resin frame 9. In other words, the protective film 13 is reliably cut, and the surface of the photoelectric conversion element array 7 on which the resin frame 9 is provided is not damaged by the irradiation of the laser light. Therefore, the occurrence of defective products is suppressed, and productivity can be improved.

[0087] Moreover, the first groove end 32 and the second groove end 33 partially overlap in a direction intersecting the extension direction of the groove 30. That is, the first groove end 32 and the second groove end 33 communicate with each other at the partially overlapping portion. Therefore, the protective film 13 can be reliably separated into the scintillator layer 8 side and the bonding pad 5 side on the resin frame 9. As a result, it is possible to remove the protective film 13 on the bonding side without damaging the photoelectric conversion element array 7.

[0088] The radiation detector 1 further includes a coating resin 14 that covers the outer edge 13a of the protective film 13. With this configuration, the occurrence of peeling of the protective film 13 can be suppressed.

[0089] The coating resin 14 further covers the resin frame 9. The coating resin 14 has viscosity and thixotropy that enable it to remain on the resin frame 9 so that an edge 14e of the contact surface between the coating resin 14 and the resin frame 9 is formed on the resin frame 9. With this configuration, the coating resin 14 does not reach the surface of the photoelectric conversion element array 7 and the bonding pads 5 located outside the resin frame 9. Therefore, the surface of the photoelectric conversion element array 7 and the bonding pads 5 can be kept clean.

[0090] The center of resin frame 9 is higher than both edge portions of resin frame 9. The position of groove 30 is biased toward bonding pad 5 on resin frame 9. With this configuration, coating resin 14 can reliably cover outer edge 13a of protective film 13.

[0091] The width of the resin frame 9 is not less than 700 micrometers and not more than 1000 micrometers. With this configuration, the radiation detector 1 can be made compact.

[0092] The height of the resin frame 9 is not less than 100 micrometers and not more than 300 micrometers. With this configuration, the radiation detector 1 can be made compact.

[0093] The photoelectric conversion element array 7 has a rectangular shape. The resin frame 9 has a first side 9a, a second side 9b, a third side 9c, and a fourth side 9d that surround the scintillator layer 8. The overlapping region 31 is provided on the first side 9a. With this configuration, peeling of the protective film 13 can be further suppressed.

[0094] The method for manufacturing the radiation detector 1 includes the steps of preparing a light receiving section 3 including a plurality of photoelectric conversion elements 3a arranged one-dimensionally or two-dimensionally, and a photoelectric conversion element array 7 having a plurality of bonding pads 5 electrically connected to the photoelectric conversion elements 3a and arranged on the outside of the light receiving section 3, step S2 of stacking a scintillator layer 8 that converts radiation into light on the photoelectric conversion element array 7 so as to cover the light receiving section 3, step S3 of arranging a resin frame 9 on the photoelectric conversion element array 7 so as to surround the scintillator layer 8 when viewed from the stacking direction of the scintillator layer 8, steps S4a, S4b, and S4c of forming a protective film 13 so as to cover the entire surface of the photoelectric conversion element array 7 on the side where the scintillator layer 8 is stacked and the surface of the resin frame 9, step S5 of cutting the protective film 13 by irradiating laser light along the resin frame 9, and step S6 of removing the outer portion of the protective film 13. In process S5 of cutting the protective film 13, an outer edge 13a of the protective film 13 is formed due to the cutting of the protective film 13, and a groove 30 continuous with the outer edge 13a of the protective film 13 is formed in the resin frame 9, and laser light is irradiated so that the groove 30 has an overlap region 31 including a first groove end 32 and a second groove end 33 that partially overlap in a direction intersecting the extension direction of the groove 30.

[0095] In the manufacturing method of the radiation detector 1, in the step S5 of cutting the protective film 13, the outer edge 13a of the protective film 13 is formed and the groove 30 of the resin frame 9 is formed. The groove 30 being formed in the resin frame 9 means that the protective film 13 formed on the resin frame 9 is reliably cut. The groove 30 includes an overlapping region 31 including a first groove end 32 and a second groove end 33. Due to the partial overlap between the first groove end 32 and the second groove end 33, the depth of the groove 30 is not too deep in the overlapping region 31. As a result, it is possible to prevent the laser light from penetrating not only the protective film 13 but also the resin frame 9. In other words, the protective film 13 is reliably cut, and the surface of the photoelectric conversion element array 7 on which the resin frame 9 is provided is not damaged by the irradiation of the laser light. Therefore, the occurrence of defective products is suppressed, and the productivity can be improved.

[0096] In the method for manufacturing the radiation detector 1, the photoelectric conversion element array 7 has a rectangular shape. The resin frame 9 has a first side 9a, a second side 9b, a third side 9c, and a fourth side 9d that surround the scintillator layer 8. In step S5 of cutting the protective film 13, an overlapping region 31 is provided on the first side 9a. This step S5 can further prevent the protective film 13 from peeling off.

[0097] In the method for manufacturing the radiation detector 1, the step S5 of cutting the protective film 13 includes a step S5s of setting at least one of the positions of the four corners of the first side portion 9a as a reference position, and a step S5r of irradiating each of the first side portions 9a with laser light based on the reference position. These steps S5s and S5r enable precise control of the positions to which the laser light is irradiated.

[0098] In the method of manufacturing the radiation detector 1, the panel protection part is the resin frame 9. In step S3 of arranging the resin frame 9, the resin frame 9 is arranged on the photoelectric conversion element array 7 so as to be spaced apart from the scintillator layer 8 and the bonding pads 5, pass between the scintillator layer 8 and the bonding pads 5, and surround the scintillator layer 8. According to this step S3, the radiation detector 1 having the resin frame 9 can be manufactured.

[0099] In the method for manufacturing the radiation detector 1, in step S3 of arranging the resin frame 9, the resin frame 9 is formed so that the center of the resin frame 9 is higher than both edge portions of the resin frame 9. In step S5 of cutting the protective film 13, a laser beam is irradiated onto a position on the resin frame 9 that is biased toward the bonding pad 5. According to these steps S3 and S5, the outer edge 13a of the protective film 13 can be reliably covered with the coating resin 14.

[0100] The first embodiment of the present invention has been described above in detail. However, the present invention is not limited to the first embodiment. Various modifications of the present invention are possible within the scope of the present invention. For example, in the above description, the protective film 13 has a structure in which the inorganic film 11 is sandwiched between the first organic film 10 and the second organic film 12 made of polyparaxylylene. That is, the material of the first organic film 10 is the same as the material of the second organic film 12. For example, the material of the first organic film 10 may be different from the material of the second organic film 12. In addition, in the case where a material resistant to corrosion is used as the inorganic film 11, the protective film 13 may omit the second organic film 12. In addition, the light receiving section 3 of the radiation detector 1 described above has a plurality of photoelectric conversion elements 3a arranged two-dimensionally. The light receiving section 3 may have a plurality of photoelectric conversion elements 3a arranged one-dimensionally. In addition, the bonding pads 5 may be formed on three sides of the rectangular radiation detector 1 instead of two sides. In the above embodiment, the laser processing is performed by moving the laser light head. For example, the stage on which the radiation detector 1 is placed may be moved when irradiating the laser light.

[0101] <Second embodiment> Next, a radiation detector 1A according to the second embodiment and a manufacturing method for the radiation detector 1A will be described. The radiation detector 1 according to the first embodiment uses a resin frame 9 as a panel protection section. Specifically, during the manufacture of the radiation detector 1, the resin frame 9 is used as a member that protects the photoelectric conversion element array 7 from laser light when the protective film 13 is cut. The radiation detector 1 includes the resin frame 9 as a component.

[0102] The radiation detector 1A of the second embodiment uses a masking member M1 (see FIG. 25, etc.) as a member for protecting the photoelectric conversion element array 7 from laser light when cutting the protective film 13. This masking member M1 is removed after step S15 of cutting the protective film 20. In other words, the radiation detector 1A does not include the masking member M1 as a component.

[0103] 19 and 20, the radiation detector 1A includes a photoelectric conversion element array 7, a scintillator layer 8, and a protective film 20. The photoelectric conversion element array 7 and the scintillator layer 8 are similar to those in the first embodiment, and therefore detailed description thereof will be omitted. The protective film 20 will be described in detail below.

[0104] The protective film 20 has a main body portion 21 and an outer edge portion 22. The main body portion 21 covers the scintillator layer 8. The first organic film 10 in the main body portion 21 is provided on the scintillator layer 8. The first organic film 10 fills the spaces between the multiple scintillators 8a having a columnar structure. The outer edge portion 22 is provided on the outside of the main body portion 21. The outer edge portion 22 is continuous with the main body portion 21.

[0105] The outer edge portion 22 has an adhesive portion 23 and an extension portion 24. The adhesive portion 23 is in close contact with the photoelectric conversion element array 7 in a region K between the scintillator layer 8 and the bonding pad 5. For example, a part of the first organic film 10 on the side of the scintillator layer 8 in the adhesive portion 23 has an adhesive surface with the photoelectric conversion element array 7. As a result, the adhesive portion 23 is in close contact with the photoelectric conversion element array 7. By increasing the adhesive surface, the adhesiveness between the adhesive portion 23 and the photoelectric conversion element array 7 is improved. In other words, increasing the adhesive surface is equivalent to increasing the length g1+g2 of the adhesive portion.

[0106] The adhesive portion 23 has a first portion 23a and a second portion 23b. The first portion 23a is a portion located on the main body portion 21 side. The first portion 23a has a first organic film 10, an inorganic film 11, and a second organic film 12. That is, the first portion 23a has a three-layer structure. The second portion 23b is located on the opposite side of the main body portion 21 with the first portion 23a in between. The second portion 23b has a first organic film 10 and a second organic film 12. That is, the second portion 23b has a two-layer structure. Therefore, the position of the outer edge 11a of the inorganic film 11 is on the inside of the outer edge 20a of the protective film 20. In other words, the inside of the outer edge 20a of the protective film 20 is the scintillator layer 8 side. In the first portion 23a, the inorganic film 11 is sandwiched between the outer edge portion 10b of the first organic film 10 and the outer edge portion 12b of the second organic film 12. The second portion 23b is located outside the outer edge portion 11b of the inorganic film 11. In other words, the second portion 23b is located closer to the bonding pad 5 than the outer edge portion 11b of the inorganic film 11. The outer edge portion 10b of the first organic film 10 is bonded to the outer edge portion 12b of the second organic film 12 in the second portion 23b. When the first organic film 10 and the second organic film 12 are made of the same material, the first organic film 10 and the second organic film 12 may be integrated. In the adhesion portion 23, the outer edge portion 10b of the first organic film 10 and the outer edge portion 12b of the second organic film 12 cooperate to surround the outer edge portion 11b of the inorganic film 11.

[0107] The extension portion 24 has a two-layer structure consisting of the first organic film 10 and the second organic film 12. The extension portion 24 extends in a self-supporting state from the contact portion 23 to the opposite side of the photoelectric conversion element array 7. The extension portion 24 is located on the outermost edge 20a side of the protective film 20. Therefore, the outer edge 10a of the first organic film 10 and the outer edge 12a of the second organic film 12 form the outer edge 20a of the protective film 20. The extension portion 24 has a rising portion 24a and a piece portion 24b. The rising portion 24a extends in the normal direction of the surface of the photoelectric conversion element array 7 from a portion of the contact portion 23 opposite to the main body portion 21 as a base end. Here, the "self-supporting state" refers to a state in which the rising portion 24a stands upright without being held or supported by any member (e.g., resin, etc.). The base end portion of the rising portion 24a is connected to the contact portion 23. The remaining portion of the rising portion 24a other than the base end portion is not in contact with any element of the radiation detector 1A.

[0108] The rising portion 24a extends in a self-supporting state in the normal direction of the surface of the photoelectric conversion element array 7. In other words, the rising portion 24a stands upright from the photoelectric conversion element array 7. However, the extending direction of the rising portion 24a is not limited to this. The rising portion 24a may extend in a self-supporting state in a direction intersecting with the direction parallel to the surface of the photoelectric conversion element array 7. For example, the rising portion 24a may be inclined toward the bonding pad 5 side based on the state in which it stands upright from the photoelectric conversion element array 7. The rising portion 24a may be inclined toward the scintillator layer 8 side based on the state in which it stands upright from the photoelectric conversion element array 7. The shape of the rising portion 24a is not limited to a flat surface. The shape of the rising portion 24a may be, for example, a curved surface.

[0109] The piece 24b protrudes from the upper portion of the rising portion 24a toward the bonding pad 5. The protruding direction of the piece 24b is parallel to the surface of the photoelectric conversion element array 7. However, the protruding direction of the piece 24b is not limited to a direction parallel to the surface of the photoelectric conversion element array 7. The protruding direction of the piece 24b may be different from the extending direction of the rising portion 24a. For example, the piece 24b may be inclined so as to gradually approach the photoelectric conversion element array 7 based on a state in which it is parallel to the surface of the photoelectric conversion element array 7. The piece 24b may be inclined so as to gradually move away from the photoelectric conversion element array 7. In addition, the shape of the piece 24b is not limited to a flat surface. The shape of the piece 24b may be, for example, a curved surface.

[0110] In FIG. 20, length g1 and length g2 indicate the length of the adhesion portion 23. Specifically, length g1 indicates the length of the first portion 23a of the adhesion portion 23. Length g2 indicates the length of the second portion 23b of the adhesion portion 23. The total length of length g1 and length g2 is, for example, about 1000 μm. Alternatively, the total length of length g1 and length g2 is, for example, 1000 μm or less. Length g3 is the height of the rising portion 24a. In other words, length g3 is the height of the extension portion 24. Length g3 is, for example, 80 μm or more and 250 μm or less. Length g4 is the length of the piece portion 24b of the extension portion 24. Length g4 is, for example, about 300 μm. Alternatively, length g4 is, for example, 300 μm or less. Length g5 is the distance from the boundary between the adhesion portion 23 and the extension portion 24 to the bonding pad 5. The length g5 is longer than the length g4. For example, the length g5 is longer than the length g4 by, for example, several tens of μm to several hundreds of μm. With this configuration, the extension 24 does not interfere with the bonding pad 5.

[0111] Here, the external shape of the radiation detector 1A will be described. FIG. 21 is a perspective view showing a corner portion of the radiation detector 1A, and FIG. 22 is a perspective view showing a corner portion of the radiation detector 1A viewed from an angle different from that of FIG. 21. FIG. 22 shows a cross section of the scintillator layer 8 covered with the protective film 20 so that the scintillator layer 8 can be seen. FIG. 22 shows a plurality of scintillators 8a having a columnar structure by broken lines. As can be seen from FIG. 21 and FIG. 22, the outer edge portion 22 of the protective film 20 has an adhesion portion 23 and an extension portion 24. The rising portion 24a is inclined toward the bonding pad 5, and the piece portion 24b may also be inclined toward the bonding pad 5. The connection portion between the rising portion 24a and the piece portion 24b may be smoothly bent instead of being bent at a right angle.

[0112] <Actions and effects of radiation detectors> The effects of the radiation detector 1A will be described. In the radiation detector 1A, the outer edge portion 22 of the protective film 20 covering the scintillator layer 8 has a contact portion 23 that is in close contact with the photoelectric conversion element array 7. This can prevent moisture from passing between the protective film 20 and the photoelectric conversion element array 7 and entering toward the scintillator layer 8. Furthermore, the outer edge portion 22 of the protective film 20 has an extension portion 24. The extension portion 24 extends in a self-supporting state from the contact portion 23 to the opposite side of the photoelectric conversion element array 7. If the outer edge portion 22 of the protective film 20 does not have the extension portion 24, the outer edge 20a of the protective film 20 is included in the contact portion 23. In that case, it is particularly difficult to ensure the adhesion between the part of the contact portion 23 where the outer edge 20a of the protective film 20 is located and the photoelectric conversion element array 7. As a result, moisture is more likely to enter the scintillator layer 8 from the interface between the contact portion 23 and the photoelectric conversion element array 7.

[0113] In contrast, the outer edge 22 of the protective film 20 in the radiation detector 1A has an extension 24. The outer edge 20a of the protective film 20 is not included in the contact portion 23. That is, the adhesion between the contact portion 23 and the photoelectric conversion element array 7 can be sufficiently ensured. As a result, the moisture resistance of the scintillator layer 8 can be improved compared to the case where the extension 24 is not present. Therefore, even if the outer edge of the protective film 20 is not held by a resin member (resin frame 9) as in the first embodiment, the moisture resistance of the scintillator layer 8 can be maintained. Furthermore, since there is no need to provide a resin member to support the outer edge of the protective film 20, the region K between the scintillator layer 8 and the bonding pad 5 can be narrowed. For example, when the width of the resin frame 9 is about 900 μm, the region K can be reduced by a length equivalent to this width. Therefore, the radiation detector 1A can ensure the moisture resistance of the scintillator layer 8 and suppress the expansion of the region K between the scintillator layer 8 and the bonding pad 5. That is, the region K can be reduced. As a result, it is possible to shorten the signal line 4 that electrically connects the light receiving portion 3 and the bonding pad 5. This improves the transmission speed of the electrical signal. In addition, because the signal line 4 is short, it is also possible to suppress an increase in noise.

[0114] The protective film 20 has an inorganic film 11, a first organic film 10, and a second organic film 12. The first organic film 10 is disposed on the scintillator layer 8 side with respect to the inorganic film 11. The second organic film 12 is disposed on the opposite side of the inorganic film 11 to the scintillator layer 8. Since the protective film 20 includes the inorganic film 11 in this manner, leakage of light generated in the scintillator layer 8 to the outside (parts other than the light receiving section 3) can be prevented. As a result, the sensitivity of the radiation detector 1A is improved. In addition, the first organic film 10 and the second organic film 12 are provided on both sides of the inorganic film 11. With this configuration, the first organic film 10 and the second organic film 12 can also protect the inorganic film 11.

[0115] The outer edge 11a of the inorganic film 11 is located inside the outer edge 20a of the protective film 20. The outer edge 10a of the first organic film 10 and the outer edge 12a of the second organic film 12 form the outer edge 20a of the protective film 20. The outer edge 10b of the first organic film 10 is joined to the outer edge 12b of the second organic film 12 outside the outer edge 11a of the inorganic film 11. The outer edge 10b of the first organic film 10 and the outer edge 12b of the second organic film 12 cover the outer edge 11b of the inorganic film 11. For example, even if the adhesion between the inorganic film 11 and the first organic film 10 or the adhesion between the inorganic film 11 and the second organic film 12 is poor, the outer edge 11b of the inorganic film 11 is sealed by the outer edge 10b of the first organic film 10 and the outer edge 12b of the second organic film 12. Therefore, the adhesion of the second organic film 12 to the first organic film 10 can be ensured.

[0116] The inorganic film 11 is a metal film made of aluminum or silver, and therefore the inorganic film 11 can have good light reflectivity.

[0117] The height of the extension 24 is not less than 80 μm and not more than 250 μm. Therefore, the moisture resistance of the scintillator layer 8 can be ensured more reliably.

[0118] The extension portion 24 has a rising portion 24a and a piece portion 24b. The piece portion 24b protrudes from the upper portion of the rising portion 24a toward the bonding pad 5. In this manner, the extension portion 24 has not only the rising portion 24a but also the piece portion 24b. Therefore, the outer edge 20a of the protective film 20 can be sufficiently far from the contact portion 23. As a result, the adhesion of the photoelectric conversion element array 7 to the contact portion 23 can be more reliably ensured. Even in this case, the length of the piece portion 24b is, for example, about 300 μm. Alternatively, the length of the piece portion 24b is, for example, 300 μm or less. Therefore, the area K between the scintillator layer 8 and the bonding pad 5 can be reduced.

[0119] For example, when a conductive member such as a wire is bonded to the bonding pad 5 in a wiring process, there is a possibility that foreign matter or the like may fly from the bonding portion toward the scintillator layer 8. Even in this case, the extension portion 24 functions as a protective wall that protects the scintillator layer 8 from the foreign matter or the like. This makes it possible to prevent contamination of the scintillator layer 8 during bonding.

[0120] Some photoelectric conversion element arrays 7 are expensive. When the radiation detector 1A does not meet the quality standards as a result of inspection in the manufacturing process, it is possible to reuse the photoelectric conversion element array 7. In that case, the scintillator layer 8 provided on the photoelectric conversion element array 7 is removed, and a new scintillator layer 8 is provided on the photoelectric conversion element array 7. To do this, the protective film 20 must be removed. According to the radiation detector 1A of this embodiment, the outer edge portion 22 of the protective film 20 has an extension portion 24. For example, when peeling the protective film 20 from the photoelectric conversion element array 7, the extension portion 24 can be used as a starting point for peeling, such as by gripping and pulling up the extension portion 24. Therefore, the extension portion 24 allows the protective film 20 to be removed relatively easily.

[0121] <Manufacturing method of radiation detector> Next, each step of the manufacturing method of the radiation detector 1A will be described with reference to Fig. 23 to Fig. 28. First, as shown in Fig. 23(a), a photoelectric conversion element array 7 is prepared (step S11). Next, as shown in Fig. 23(b), a scintillator layer 8 is provided on the photoelectric conversion element array 7 so as to cover the light receiving section 3 (step S12).

[0122] Next, as shown in FIG. 24(a), a masking material M1 is provided on the photoelectric conversion element array 7 so as to cover the bonding pads 5 (step S13). An example of the masking material M1 is a UV-curable masking tape. Hereinafter, the UV-curable masking tape is simply referred to as a "UV tape". A plurality of bonding pads 5 are arranged along the outer edge of the substrate 2. First, the longitudinal direction of the UV tape is aligned with the arrangement direction of the bonding pads 5. Next, the adhesive surface of the UV tape is attached to the photoelectric conversion element array 7 so that the UV tape covers the bonding pads 5. The thickness of the UV tape may be, for example, about 110 μm. The thickness of the UV tape may be 110 μm or less. To adjust the thickness of the masking material M1, a plurality of UV tapes may be overlapped.

[0123] A protective film 20 is provided on the photoelectric conversion element array 7 so as to cover the scintillator layer 8, the region K, and the masking member M1 (step S14). Specifically, first, as shown in FIG. 24(b), a first organic film 10 is formed (step S14a). For example, the entire surface of the substrate 2 is covered with polyparaxylylene or the like by a CVD method. Next, as shown in FIG. 25(a), an inorganic film 11 is formed on the first organic film 10 (step S14b). For example, an aluminum film is laminated on the inorganic film 11 by a vapor deposition method. Here, the bonding pads 5 may not be covered with the inorganic film 11. In that case, it is preferable to mask the bonding pads 5 with a masking member M2 and then vapor-deposit the aluminum film. For example, a UV tape may be used as the masking member M2. Then, as shown in FIG. 25(b), a second organic film 12 is formed (step S14c). For example, the entire surface of the substrate 2 is covered with polyparaxylylene or the like again by a CVD method.

[0124] 26, the protective film 20 on the masking member M1 is cut by irradiating it with laser light L (step S15). For example, the laser light L is scanned along the edge of the masking member M1 on the scintillator layer 8 side by moving a laser light head (not shown) that irradiates the laser light L relative to a stage (not shown) on which the substrate 2 is placed.

[0125] 27, the masking member M1 has a first side M1a, a second side M1b, a third side M1c, and a fourth side M1d. Laser light L is then applied to the first side M1a of the masking member M1 so that a groove 30A having an overlapping region 31A is formed. The specific process may be the same as process S7 of the first embodiment.

[0126] The masking member M1 is removed (step S16). Specifically, the adhesive strength of the adhesive surface of the masking member M1, which is a UV tape, is reduced, and then the masking member M1 is removed. First, as shown in FIG. 28(a), ultraviolet rays are irradiated toward the masking member M1 (step S16a). The ultraviolet rays penetrate the protective film 20 and reach the masking member M1. The masking member M1 loses the adhesive strength of the adhesive surface by being irradiated with ultraviolet rays. Then, as shown in FIG. 28(b), the masking member M1 is removed (step S16b). The portion of the cut protective film 20 that covered the masking member M1 is removed together with the masking member M1. As a result, the bonding pad 5 is exposed.

[0127] <Action and effect> In the method for manufacturing the radiation detector 1A, the panel protection part is a masking member M1. In step S13 of arranging the masking member M1, the masking member M1 is arranged on the photoelectric conversion element array 7 so as to cover the bonding pads 5 and the region K between the scintillator layer 8 and the bonding pads 5. In step S14 of forming the protective film 20, the protective film 20 is formed on the entire surface of the photoelectric conversion element array 7 on the side where the scintillator layer 8 is laminated and on the surface of the masking member M1. According to this step S14, it is possible to manufacture the radiation detector 1A without the resin frame 9. In other words, it is possible to reduce the distance between the scintillator layer 8 and the bonding pads 5, and therefore the radiation detector 1A can be further miniaturized.

[0128] The method for manufacturing the radiation detector 1A further includes a step S16b of removing the masking member M1 after the step S16a of removing the outer portion of the protective film 20. According to these steps 16a and 16b, the radiation detector 1A not including the resin frame 9 can be suitably manufactured.

[0129] 29, the method for manufacturing radiation detector 1A may further include, after step S16a of removing the outer portion of protective film 20, a step of forming coating resin 14A to cover outer edge 20a of protective film 20. This step can further prevent outer edge 20a of protective film 20 from peeling off.

[0130] According to the above-described manufacturing method of the radiation detector 1A, the bonding pad 5 is covered with the masking member M1, and the protective film 20 is provided so as to cover the scintillator layer 8, the region between the scintillator layer 8 and the bonding pad 5, and the masking member M1. As a result, the protective film 20 has a contact portion 23 that is in close contact with the photoelectric conversion element array 7 in the region K between the scintillator layer 8 and the bonding pad 5. Furthermore, a step is generated between the end face of the masking member M1 and the photoelectric conversion element array 7 due to the thickness of the masking member M1. The protective film 20 is formed along the step. As a result, the protective film 20 has an extension portion 24 that extends from the contact portion 23 to the opposite side of the photoelectric conversion element array 7. Furthermore, the laser light L is irradiated along the edge of the masking member M1 on the scintillator layer 8 side. As a result, the protective film 20 is cut on the masking member M1. Then, the masking member M1 is removed. As a result, the bonding pad 5 is exposed. Furthermore, the extension portion 24 is independent without contacting the masking member M1. The extension portion 24 has a rising portion 24a and a piece portion 24b. The rising portion 24a is formed along a step caused by the edge of the masking member M1. The piece portion 24b is formed between the rising portion 24a and the edge of the masking member M1 that has been irradiated with the laser.

[0131] The radiation detector 1A has a contact portion 23 and an extension portion 24. The contact portion 23 is in close contact with the photoelectric conversion element array 7 in a region K between the scintillator layer 8 and the bonding pad 5. The extension portion 24 extends in a free-standing state from the contact portion 23 to the opposite side of the photoelectric conversion element array 7. Furthermore, the extension portion 24 includes a rising portion 24a and a piece portion 24b. With these structures, as described above, the moisture resistance of the scintillator layer 8 can be maintained. Furthermore, the region K between the scintillator layer 8 and the bonding pad 5 can be narrowed.

[0132] Here, there is a possibility that the bonding pad 5 may be damaged by irradiation with the laser light L. However, in the above-described method for manufacturing the radiation detector 1A, when the protective film 20 is cut, the bonding pad 5 is covered with the masking member M1. At this time, the masking member M1 serves as an absorption layer that absorbs the laser light L. Therefore, it is possible to prevent the bonding pad 5 from being damaged by irradiation with the laser light L.

[0133] In the above-described method for manufacturing the radiation detector 1A, the protective film 20 is cut by irradiation with laser light L (step S15). This step S15 makes it possible to accurately shape the adhesion portions 23 and the extension portions 24 at the outer edge portion 22 of the protective film 20. Even when the bonding pads 5 are arranged at predetermined intervals along not only one side of the outer edge of the substrate 2 but also multiple sides (e.g., two to four sides), it is sufficient to scan the laser light L along each side. Therefore, the adhesion portions 23 and the extension portions 24 can be easily shaped at the outer edge portion 22.

[0134] Although the second embodiment of the present invention has been described above, the present invention is not limited to the above embodiment. For example, the outer edge 11a of the inorganic film 11 may constitute the outer edge 20a of the protective film 20 together with the outer edge 10a of the first organic film 10 and the outer edge 12a of the second organic film 12.

[0135] The inorganic film 11 may be a resin film containing a white pigment. Examples of the white pigment include alumina, titanium oxide, zirconium oxide, and yttrium oxide. When the inorganic film 11 is a resin film containing a white pigment, after the second organic film 12 is formed, a metal film (e.g., aluminum) and a third protective film (made of the same material as the first and second organic films) are further laminated in this order, so that even a resin reflective film with poor moisture resistance can have moisture resistance equivalent to that of a metal reflective film and a light output equal to or greater than that of a metal reflective film. In this way, an inorganic film 11 with light reflectivity can be realized.

[0136] <Third embodiment> In the first embodiment, the formation of excessively deep grooves in the resin frame 9 by the laser light is suppressed. Similarly, in the second embodiment, the formation of excessively deep grooves in the masking member M1 by the laser light is suppressed. All of these excessively deep grooves are caused by the irradiation of excessive energy to the resin frame 9 and the masking member M1. One of the causes of the irradiation of this excessive energy is that the same position of the irradiated object, such as the resin frame 9 and the masking member M1, is irradiated with laser light multiple times. Therefore, in the first and second embodiments, a method of shifting the scan line is presented so that the same position is not irradiated with laser light multiple times.

[0137] A method different from those of the first and second embodiments will be described below. In the following description, an example will be described in which a method different from those of the first and second embodiments is applied to the manufacture of the radiation detector 1 of the first embodiment. Note that the method of the third embodiment can also be applied to the manufacture of the radiation detector 1A of the second embodiment.

[0138] In the irradiation of the laser light for cutting the protective film 13 (step S5), the irradiation of excessive energy may occur due to factors other than the cause of the irradiation target being irradiated with the laser light multiple times at the same position.

[0139] Figures 30(a) and 30(b) show the concept of controlling laser light. Figure 30(a) shows the time history of the energy received by the irradiated object. Figure 30(b) shows the time history of the velocity of the laser light head.

[0140] Here, the cutting threshold is defined. The cutting threshold is a value at which the irradiated object is cut when the irradiated object is irradiated with energy equal to or greater than this value. In this specification, "cutting" refers to the formation of a void that penetrates from the surface irradiated with the laser light to the back surface of the irradiated object. Therefore, if the void does not penetrate from the surface irradiated with the laser light to the back surface and has a bottom, it is not called "cutting".

[0141] The cutting threshold is determined according to the type of material, the thickness of the target, and the like. Taking the radiation detector 1 of the first embodiment as an example, as shown in FIG. 30(a), a cutting threshold Q1 for the protective film 13 and a cutting threshold Q2 for the resin frame 9 are set. The cutting threshold Q2 for the resin frame 9 is greater than the cutting threshold Q1 for the protective film 13. In step S5 of cutting the protective film 13, the protective film 13 is cut, and the resin frame 9 is not cut. Then, in FIG. 30(a), the energy (Qs) of the laser light to be irradiated may be between the cutting threshold Q2 for the resin frame 9 and the cutting threshold Q1 for the protective film 13.

[0142] When starting to irradiate the laser light, the time it takes for the energy of the laser light on the surface of the irradiated object to rise from zero (non-irradiation) to a predetermined energy (t1 in Figure 30(a)) is much shorter than the time it takes for the moving speed of the laser light head to reach a predetermined speed from zero (t1 to t3 in Figure 30(b)).

[0143] Then, the energy (Q3 to Qs) of the laser light that the irradiated object receives per unit time (length) during the acceleration period (t1 to t3) from when the moving speed of the laser light head reaches a predetermined speed from zero is different from the energy (Qs) of the laser light that the irradiated object receives per unit time (length) during the steady period (t3 to t4) during which the laser light head moves at a predetermined speed. Specifically, the moving speed (0 to Vs) of the laser light head during the acceleration period (t1 to t3) is slower than the moving speed (Vs) of the laser light head during the steady period (t3 to t4). Therefore, the energy (Q3 to Qs) of the laser light that the irradiated object receives during the acceleration period (t1 to t3) is greater than the energy (Qs) of the laser light that the irradiated object receives during the steady period (t3 to t4). Therefore, if the speed of the laser light head is too slow compared to the energy of the laser light during this acceleration period (t1 to t3), excessive energy may be irradiated to the irradiated object. If this energy exceeds the energy (Q2) at which the resin frame 9 breaks, the photoelectric conversion element array 7 present below the resin frame 9 may be damaged.

[0144] Such a phenomenon may also occur when the irradiation of the laser light is stopped. Therefore, the irradiation mode of the laser light is controlled so that the irradiated object does not receive excessive energy when the irradiation of the laser light is started and when the irradiation of the laser light is stopped.

[0145] For example, the history of the energy (hereinafter referred to as "unit energy") per unit length (time) received by the irradiated object from the start of irradiation with laser light to the end of irradiation is set as shown in Fig. 31. The energy history includes a period ta in which the unit energy is maintained, a period ts in which the unit energy is increased, and a period te in which the unit energy is decreased.

[0146] The period ta during which the unit energy is maintained is a period during which the planned groove 30 is formed. In the first embodiment, the period ta corresponds to a period during which the first irradiation line R1, the second irradiation line R2, the third irradiation line R3, and the fourth irradiation line R4 shown in Fig. 12 are formed. Therefore, the steady value Qs, which is the energy during this period ta, is greater than the cut threshold Q1 of the protective film 13 and less than the cut threshold Q2 of the resin frame 9.

[0147] The period ts during which the unit energy is increased corresponds to the period of the front irradiation line RS. This period ts includes a section ts1 during which the unit energy is increased from a value (Q0) smaller than the cut threshold Q1 to the cut threshold Q1 of the protective film 13, and a section ts2 during which the unit energy is increased from the cut threshold Q1 of the protective film 13 to a steady value Qs. The groove 30 formed during the period ts during which the unit energy is increased has a depth that gradually deepens along the scanning direction of the laser light. For example, the section ts2 may correspond to the formation of the first groove end 32 shown in FIG. 5.

[0148] The period te during which the unit energy is reduced corresponds to the period of the post-irradiation line RE. This period te includes a section te2 during which the unit energy is reduced from the steady value Qs to the cut threshold Q1 of the protective film 13, and a section te1 during which the unit energy is reduced from the cut threshold Q1 of the protective film 13 to a value (Q0) smaller than the cut threshold Q1. The groove formed during the period te during which the unit energy is reduced has a depth that gradually becomes shallower along the scanning direction of the laser light. For example, the section te2 may correspond to the formation of the second groove end 33 shown in FIG. 5.

[0149] The history of unit energy shown in Fig. 31 can be realized by one control variable selected from several control variables. Also, the history of unit energy can be realized by combining a plurality of control variables.

[0150] For example, the control variables include the moving speed of the laser light head, the irradiation energy of the laser light, and the focal position of the laser light.

[0151] Fig. 32(a) shows an example of the history of the moving speed of the laser light head to realize the history of the unit energy in Fig. 31. In period ts, the speed decelerates (V0→Vs) over time. In period ta, the speed (Vs) is maintained. In period te, the speed increases (Vs→V0) over time.

[0152] Fig. 32(b) is an example of the history of the irradiation energy of the laser light to realize the history of the unit energy in Fig. 31. In the period ts, the energy is increased over time (Q0→Qs). In the period ta, the energy (Qs) is maintained. In the period te, the energy is decreased over time (Qs→Q0).

[0153] Fig. 32(c) is an example of the history of the focal position of the laser light to realize the history of the unit energy in Fig. 31. In the period ts, the focal position is moved closer to the surface of the irradiated object over time (P0→Ps). In the period ta, the focal position is maintained on the surface of the irradiated object (Ps). In the period te, the focal position is moved away from the surface of the irradiated object over time (Ps→P0).

[0154] According to the above-mentioned aspect of controlling the laser light, it is possible to more reliably prevent the laser light from penetrating not only the scintillator protective film but also the resin frame. In other words, the scintillator protective film is reliably cut, and the surface of the light detection panel provided with the resin frame is not damaged by the irradiation of the laser light. Therefore, the occurrence of defective products is suppressed, and productivity can be improved.

[0155] <Fourth embodiment> The problem described in the third embodiment can be solved by a different control mode from that described in the third embodiment. The problem described at the beginning of the third embodiment is based on the premise that the timing of starting the irradiation of the laser light and the timing of starting the movement of the laser light head are simultaneous. For example, by shifting the timing of starting the irradiation of the laser light and the timing of starting the movement of the laser light head, it is possible to prevent the irradiation of an excessive amount of energy to the irradiated object.

[0156] For example, when starting irradiation of laser light, the operation is as follows. First, the movement of the laser light head is started (t0 in FIG. 33(a)). At this time, irradiation of laser light is not started. As time passes (t0→t1), the speed of the laser light head increases. Then, when the speed of the laser light head reaches a predetermined value (Va), irradiation of laser light is started. This predetermined value may be the steady speed (Vs), or may be a value greater than the speed threshold value (V1) shown in FIG. 30(b) and less than the steady speed (Vs). In other words, the timing (ts) at which irradiation of laser light starts is set after the timing (t0) at which the movement of the laser light head starts.

[0157] Moreover, when emitting the laser light, the timing to stop the emission of the laser light is set before the timing to stop the movement of the laser light head. For example, the emission of the laser light may be stopped when the speed of the laser light head is at a steady speed (Vs). In the period in which the speed of the laser light head is decelerated, the emission of the laser light may be stopped during the period in which the speed is capable of emitting a unit energy below the cutting threshold value Q1 of the resin frame 9. Also, as described in the third embodiment, when the speed of the laser light head increases, the energy per unit length decreases. Therefore, the emission of the laser light may be stopped while the speed of the laser light head is increased.

[0158] According to the above-mentioned aspect of controlling the laser light, it is possible to more reliably prevent the laser light from penetrating not only the scintillator protective film but also the resin frame. In other words, the scintillator protective film is reliably cut, and the surface of the light detection panel provided with the resin frame is not damaged by the irradiation of the laser light. Therefore, the occurrence of defective products is suppressed, and productivity can be improved.

[0159] In the step S5 of cutting the protective film 13, the method shown in the first embodiment may be combined with only the method shown in the third embodiment. Also, the method shown in the first embodiment may be combined with only the method shown in the fourth embodiment. Furthermore, the method shown in the first embodiment may be combined with the method shown in the fourth embodiment in addition to the method shown in the third embodiment. [Explanation of symbols]

[0160] DESCRIPTION OF SYMBOLS 1,1A...radiation detector, 2...substrate, 3...light receiving portion, 3a...photoelectric conversion element, 4...signal line, 5...bonding pad, 6...passivation film, 7...photoelectric conversion element array, 8...scintillator layer, 8a...scintillator, 8b...periphery, 9...resin frame, 10...first organic film, 11...inorganic film (metal film), 12...second organic film, 13...protective film, 13a...outer edge of protective film 13, 14...coating resin, 30...groove, D1...first distance, D2...second distance, d,d1,d3...height, d2...width, E1...inner edge of resin frame 9, E2...outer edge of resin frame 9, E3...outer edge of scintillator layer 8, E4...outer edge of photoelectric conversion element array 7, M1...masking member.

Claims

1. a light detection panel having a light receiving section including a plurality of photoelectric conversion elements arranged one-dimensionally or two-dimensionally, and a plurality of bonding pads electrically connected to the photoelectric conversion elements and arranged outside the light receiving section; a scintillator layer that is laminated on the light detection panel so as to cover the light receiving portion and converts radiation into light; a resin frame formed on the light detection panel so as to be spaced apart from the scintillator layer and the bonding pad, pass between the scintillator layer and the bonding pad, and surround the scintillator layer when viewed from a stacking direction of the scintillator layer; and a scintillator protective film covering the scintillator layer and having an outer edge positioned on the resin frame; a groove is formed in the resin frame, the groove being continuous with an outer edge of the scintillator protective film; the groove has an overlap region including a first groove end portion and a second groove end portion that partially overlap in a direction intersecting an extension direction of the groove, A radiation detector, wherein an outer part of the first groove end located on the scintillator layer side in the overlap region overlaps with an inner part of the second groove end located on the bonding pad side.

2. The radiation detector according to claim 1 , further comprising a coating resin that covers the outer edge of the scintillator protection film.

3. The coating resin further covers the resin frame, The radiation detector according to claim 2 , wherein the coating resin has material properties that enable the coating resin to remain on the resin frame such that an edge of a contact surface between the coating resin and the resin frame is formed on the resin frame.

4. A central portion of the resin frame is higher than both edge portions of the resin frame, 4. The radiation detector according to claim 2, wherein the groove is positioned on the resin frame toward the bonding pad.

5. 5. The radiation detector according to claim 1, wherein the resin frame has a width of not less than 700 micrometers and not more than 1000 micrometers.

6. The radiation detector according to claim 1 , wherein the resin frame has a height of not less than 100 micrometers and not more than 300 micrometers.

7. The light detection panel has a rectangular shape, the resin frame has four sides surrounding the scintillator layer, The radiation detector according to claim 1 , wherein the overlapping region is provided on any one of the four sides.

8. a step of preparing a light detection panel having a light receiving section including a plurality of photoelectric conversion elements arranged one-dimensionally or two-dimensionally, and a plurality of bonding pads electrically connected to the photoelectric conversion elements and arranged outside the light receiving section, and laminating a scintillator layer that converts radiation into light on the light detection panel so as to cover the light receiving section; disposing a panel protection part on the light detection panel so as to surround the scintillator layer when viewed from a stacking direction of the scintillator layer; forming a film to be a scintillator protective film so as to cover a surface of the scintillator layer, the entire surface of the light detection panel on which the scintillator layer is laminated, and a surface of the panel protective portion; cutting the film that will become the scintillator protective film by irradiating a laser beam along the panel protective portion; and removing an outer portion of the film that will become the scintillator protective film, a first groove end portion located on the bonding pad side, the first groove end portion being formed on the bonding pad side, the second groove end portion being formed on the scintillator layer ...

9. The light detection panel has a rectangular shape, the panel protection portion has four sides surrounding the scintillator layer, The method for manufacturing a radiation detector according to claim 8 , wherein in the step of cutting the film that becomes the scintillator protective film, the overlapping region is provided on any one of the four sides.

10. The step of cutting the film to be the scintillator protective film includes: setting at least one of the positions of four corners defined by the four sides as a reference position; The method for manufacturing a radiation detector according to claim 9 , further comprising: irradiating each of the four side portions with the laser light based on the reference position.

11. The panel protection portion is a resin frame, 11. The method for manufacturing a radiation detector according to claim 8, wherein in the step of arranging the panel protection part, the resin frame is arranged on the light detection panel so as to be spaced apart from the scintillator layer and the bonding pad, pass between the scintillator layer and the bonding pad, and surround the scintillator layer.

12. In the step of disposing the panel protection portion, the resin frame is formed so that a central portion of the resin frame is higher than both edge portions of the resin frame, The method for manufacturing a radiation detector according to claim 11 , wherein in the step of cutting the film that becomes the scintillator protective film, the laser light is irradiated onto a position on the resin frame that is biased toward the bonding pad.

13. the panel protection portion is a masking member, In the step of disposing the panel protection portion, the masking member is disposed on the light detection panel so as to cover an outer region between the scintillator layer and the bonding pads and the bonding pads; 11. The method for manufacturing a radiation detector according to claim 8, wherein in the step of forming a film that will become the scintillator protective film, the film that will become the scintillator protective film is formed on a surface of the scintillator layer, the entire surface of the light detection panel on which the scintillator layer is laminated, and a surface of the masking member.

14. The method for manufacturing a radiation detector according to claim 13 , further comprising the step of removing the masking member after the step of removing an outer portion of the film that will become the scintillator protective film.

15. 15. The method for manufacturing a radiation detector according to claim 13, further comprising the step of forming a coating resin that covers the outer edge of the scintillator protective film after the step of removing an outer portion of the film that will become the scintillator protective film.

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