Flat panel detector and manufacturing method thereof

Abstract

The invention belongs to the field of display, and particularly relates to a flat panel detector and a manufacturing method thereof.The flat panel detector comprises an array substrate and a diffusion substrate, the diffusion substrate is arranged on one side of the array substrate, the diffusion substrate and the array substrate are arranged in a spaced mode, and the orthographic projection of the diffusion substrate on the array substrate is located in the array substrate; the array substrate comprises a thin film transistor and a photodiode, the diffusion substrate comprises a first substrate body, a diffusion film and a scintillator, the scintillator is formed on the side, away from the array substrate, of the first substrate body, and the diffusion film is formed on the side, close to the array substrate, of the first substrate body and used for evenly dispersing visible light converted by the scintillator. Because the diffusion film can uniformly disperse the visible light converted by the scintillator, the area of the array substrate can be larger than the area of the scintillator, and the minimum detection unit number and spacing of the array substrate and the photosensitive area of the photodiode can be increased, that is, the resolution and resolution of the flat panel detector can be improved.

Description

Technical Field

[0001] The present application belongs to the field of display, and specifically relates to a flat panel detector and a manufacturing method thereof. Background Art

[0002] Flat X-ray Panel Detector (FPXD) based on Thin Film Transistor (TFT) technology is a crucial component in digital imaging technology. Due to its advantages such as fast imaging speed, good spatial and density resolution, high signal-to-noise ratio, and direct digital output, it has been widely used in industry, medicine, aviation and other fields.

[0003] The flat-panel detector includes an array substrate and a scintillator formed on one side of the array substrate. The array substrate includes a minimum detection unit consisting of a thin-film transistor and a photodiode. The photodiode can convert visible light into an electrical signal. When the thin-film transistor is turned on, the above electrical signal is output to the processor, which processes it to obtain image information.

[0004] The larger the photodiode's photosensitive area, the more sensitive it is. The flat-panel detector's sensitivity determines that the photodiode's photosensitive area cannot be too small. Given the limited size of a flat-panel detector, ensuring the photodiode's photosensitive area is difficult to improve, making it difficult to adapt to scenarios where the objects being detected are small and require higher resolution and higher resolution. Summary of the Invention

[0005] The purpose of this application is to provide a flat panel detector and a manufacturing method thereof, so as to improve the resolution and resolution of the flat panel detector.

[0006] To achieve the above-mentioned object, the present application provides a flat panel detector, comprising an array substrate, the flat panel detector further comprising a diffusion substrate, the diffusion substrate being disposed on one side of the array substrate, the diffusion substrate being spaced apart from the array substrate, the orthographic projection of the diffusion substrate on the array substrate being located within the array substrate, the diffusion substrate comprising:

[0007] a first substrate;

[0008] a scintillator, formed on a side of the first substrate away from the array substrate, and configured to convert X-rays into visible light;

[0009] A diffusion film is formed on a side of the first substrate close to the array substrate, and is used to uniformly disperse the visible light converted by the scintillator.

[0010] Optionally, the diffusion film includes a first lens film, and the first lens film is recessed inwardly on a side away from the first substrate to form a concave lens.

[0011] Optionally, the material for making the first lens film includes silicon oxide or silicon nitride.

[0012] Optionally, the flat panel detector further includes a compensation substrate, wherein the compensation substrate is formed on a side of the array substrate close to the diffusion substrate, the compensation substrate is spaced apart from the diffusion substrate, and an orthographic projection of the compensation substrate on the array substrate coincides with the array substrate;

[0013] The compensation substrate includes a second base substrate and a light-gathering film. The second base substrate is arranged on a side of the array substrate close to the diffusion substrate. The light-gathering film is formed on a side of the second base substrate close to the diffusion substrate. The light-gathering film is used to make the visible light irradiate the array substrate vertically.

[0014] Optionally, the diffusion film includes a first lens film, and the first lens film is concave inwardly on a side away from the first substrate to form a concave lens;

[0015] The light-concentrating film includes a second lens film, and the second lens film is convex outwardly away from the second base substrate to form a convex lens.

[0016] Optionally, the refractive index of the material used to make the second lens film is the same as the refractive index of the material used to make the first lens film.

[0017] Optionally, the array substrate includes a third base substrate, a detection function layer and a focusing film, the detection function layer and the focusing film are sequentially formed on one side of the third base substrate, the focusing film is spaced apart from the diffusion substrate, and the focusing film is used to make the visible light irradiate the detection function layer vertically.

[0018] The present application also provides a method for manufacturing a flat panel detector, which is used to manufacture the flat panel detector described above, and includes:

[0019] manufacturing an array substrate;

[0020] A scintillator and a diffusion film are formed on opposite sides of a first base substrate to prepare a diffusion substrate, wherein the diffusion film includes a first lens film, and the first lens film is concave inwardly on a side away from the first base substrate to form a concave lens;

[0021] Mounting the diffusion substrate on one side of the array substrate so that the diffusion film faces the array substrate and a gap is formed between the diffusion film and the array substrate;

[0022] The method of forming the first lens film includes:

[0023] forming a first transparent material layer and a first photoresist layer in sequence on one side of the first base substrate;

[0024] exposing the first photoresist layer using a mask with a gradient transmittance, and then developing and removing a portion of the first photoresist layer, so that a side of the first photoresist layer away from the first base substrate forms an inwardly concave curved surface;

[0025] The remaining first photoresist layer and a portion of the first transparent material layer are removed by etching to form the first lens film.

[0026] Optionally, the flat panel detector further includes a compensation substrate, the compensation substrate being formed on a side of the array substrate close to the diffusion substrate, the compensation substrate being spaced apart from the diffusion substrate, and an orthographic projection of the compensation substrate on the array substrate coinciding with the array substrate, the compensation substrate including a second base substrate and a light-concentrating film, the second base substrate being provided on a side of the array substrate close to the diffusion substrate, the light-concentrating film being formed on a side of the second base substrate close to the diffusion substrate, the light-concentrating film being used to allow the visible light to vertically irradiate the array substrate, the light-concentrating film including a second lens film, the second lens film being convex outward on a side away from the second base substrate to form a convex lens;

[0027] The method of forming the second lens film includes:

[0028] forming a second transparent material layer and a second photoresist layer in sequence on one side of the second base substrate;

[0029] exposing the second photoresist layer using a mask with a gradient transmittance, and then developing and removing a portion of the second photoresist layer to form an outwardly convex curved surface on a side of the second photoresist layer away from the second base substrate;

[0030] The remaining second photoresist layer and a portion of the second transparent material layer are removed by etching to form the second lens film.

[0031] Optionally, the first lens film and the second lens film are formed using the same photomask, and the first photoresist layer and the second photoresist layer: one is made of positive photoresist and the other is made of negative photoresist.

[0032] The flat panel detector and its manufacturing method disclosed in this application have the following beneficial effects:

[0033] In the present application, a flat-panel detector includes an array substrate and a diffusion substrate. The diffusion substrate is disposed on one side of the array substrate and spaced apart from the array substrate. The orthographic projection of the diffusion substrate on the array substrate is located within the array substrate. The array substrate includes thin-film transistors and photodiodes. The diffusion substrate includes a first base substrate, a diffusion film, and a scintillator. The scintillator is formed on a side of the first base substrate away from the array substrate, and the diffusion film is formed on a side of the first base substrate close to the array substrate, and is used to uniformly disperse the visible light converted by the scintillator. Because the diffusion film can uniformly disperse the visible light converted by the scintillator, the area of ​​the array substrate can be larger than that of the scintillator. The minimum number of detection units and the spacing between them, as well as the photosensitive area of ​​the photodiodes, can be increased. That is, the resolution and resolution of the flat-panel detector can be improved.

[0034] Other features and advantages of the present application will become apparent from the following detailed description, or may be learned in part by practice of the present application.

[0035] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The accompanying drawings are incorporated into and constitute a part of the specification, illustrate embodiments consistent with the present application, and together with the specification, are used to explain the principles of the present application. Obviously, the drawings described below are only some embodiments of the present application, and those skilled in the art can derive other drawings based on these drawings without inventive effort.

[0037] Figure 1 It is a structural diagram of the flat panel detector in Example 1 of the present application.

[0038] Figure 2 Schematic diagram of the structure of the flat-panel detector in Example 2 of the present application.

[0039] Figure 3 Schematic diagram of the structure of the array substrate in Example 2 of the present application.

[0040] Figure 4 A schematic flow chart of a method for manufacturing a flat panel detector in the third embodiment of the present application.

[0041] Figure 5 Schematic diagram of exposing the first photoresist layer in Example 3 of the present application.

[0042] Figure 6 Schematic diagram of developing the first photoresist layer in Example 3 of the present application.

[0043] Figure 7 Schematic diagram of forming the first lens film in Example 3 of the present application.

[0044] Figure 8 Schematic diagram of exposing the second photoresist layer in Example 3 of the present application.

[0045] Figure 9 Schematic diagram of developing the second photoresist layer in Example 3 of the present application.

[0046] Figure 10 Schematic diagram of forming the second lens film in Example 3 of the present application.

[0047] Description of reference numerals:

[0048] 100, diffusion substrate; 110, first base substrate; 120, scintillator; 130, diffusion film; 131, first transparent material layer; 140, first photoresist layer;

[0049] 200, compensation substrate; 210, second base substrate; 220, focusing film; 221, second transparent material layer; 230, second photoresist layer;

[0050] 300, array substrate; 310, third base substrate; 320, first metal layer; 330, active layer; 340, second metal layer; 341, drain electrode; 342, source electrode; 350, third metal layer; 360, photoelectric conversion layer; 370, transparent conductive layer; 380, fourth metal layer; 381, bias electrode; 382, ​​light shielding portion; 391, gate insulating layer; 392, first passivation layer; 393, second passivation layer; 394, first planarization layer; 395, third passivation layer; 396, second planarization layer;

[0051] 400. Photomask. DETAILED DESCRIPTION

[0052] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided so that this application will be thorough and complete and will fully convey the concepts of the example embodiments to those skilled in the art.

[0053] In addition, described feature, structure or characteristic can be combined in one or more embodiments in any suitable manner.In the following description, many specific details are provided so as to provide a full understanding of the embodiments of the present application. However, it will be appreciated by those skilled in the art that the technical scheme of the present application can be put into practice without one or more of the specific details, or other methods, components, devices, steps etc. can be adopted. In other cases, known methods, devices, implementations or operations are not shown or described in detail to avoid blurring the various aspects of the application.

[0054] The present application is further described below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the technical features involved in the various embodiments of the present application described below can be combined with each other as long as they do not conflict with each other. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be understood as limiting the present application.

[0055] Example 1

[0056] See also Figure 1 As shown, in this embodiment, the flat panel detector includes an array substrate 300 and a diffuser substrate 100. The diffuser substrate 100 is disposed on one side of the array substrate 300 and spaced apart from the array substrate 300. The spacing between the diffuser substrate 100 and the array substrate 300 can be maintained by a frame, or by using transparent spacers. The orthographic projection of the diffuser substrate 100 on the array substrate 300 is located within the array substrate 300. In other words, the outer dimensions of the array substrate 300 are larger than those of the diffuser substrate 100.

[0057] The array substrate 300 includes a minimum detection unit consisting of a thin film transistor and a photodiode. The photodiode can convert visible light into an electrical signal. When the thin film transistor is turned on, the electrical signal is output to the processor and processed by the processor to obtain image information.

[0058] The diffusion substrate 100 includes a first base substrate 110, a diffusion film 130, and a scintillator 120. The first base substrate 110 can be a transparent substrate such as a glass substrate or a polyimide substrate. The scintillator 120 is formed on the side of the first base substrate 110 away from the array substrate 300 and is used to convert X-rays into visible light. The diffusion film 130 is formed on the side of the first base substrate 110 close to the array substrate 300 and is used to evenly disperse the visible light converted by the scintillator 120. Figure 1 As shown, Figure 1 The middle arrow represents the light.

[0059] The larger the photodiode's photosensitive area, the more sensitive it is. The flat-panel detector's sensitivity determines that the photodiode's photosensitive area cannot be too small. Given the limited size of a flat-panel detector, ensuring the photodiode's photosensitive area is difficult to improve, making it difficult to adapt to scenarios where the objects being detected are small and require higher resolution and higher resolution.

[0060] In this embodiment, the flat panel detector includes an array substrate 300 and a diffuser substrate 100. The diffuser substrate 100 is disposed on one side of the array substrate 300 and spaced apart from the array substrate 300. The orthographic projection of the diffuser substrate 100 on the array substrate 300 is located within the array substrate 300. The array substrate 300 includes a minimum detection unit consisting of a thin-film transistor and a photodiode. The diffuser substrate 100 includes a first base substrate 110, a diffuser film 130, and a scintillator 120. The scintillator 120 is formed on the side of the first base substrate 110 away from the array substrate 300 and is used to convert X-rays into visible light. The diffuser film 130 is formed on the side of the first base substrate 110 closer to the array substrate 300 and is used to evenly disperse the visible light converted by the scintillator 120. Because the diffuser film 130 evenly disperses the visible light converted by the scintillator 120, the area of ​​the array substrate 300 can be larger than that of the scintillator 120. This increases the number and spacing of the minimum detection units on the array substrate 300, as well as the photosensitive area of ​​the photodiodes. This improves the resolution and resolution of the flat panel detector.

[0061] In some embodiments, the diffusion film 130 includes a first lens film, which is recessed inwardly on a side away from the first substrate 110 to form a concave lens. The closer the first lens film is to the center, the deeper the recess. In other words, the entire first lens film is a concave lens.

[0062] The diffusion film 130 is a first lens film. The side of the first lens film away from the first base substrate 110 is concave inward to form a concave lens. The diffusion film 130 has a simpler structure and can reduce the manufacturing cost of the flat panel detector.

[0063] It should be noted that the first lens film is concave inward on the side away from the first base substrate 110 to form a concave lens, and the entire first lens film is a concave lens, but is not limited to this. The first lens film may also include a plurality of micro concave lens structures arranged in an array, depending on the specific situation.

[0064] In some embodiments, the first lens film is made of a material including silicon oxide or silicon nitride.

[0065] Inorganic materials such as silicon oxide and silicon nitride have high light transmittance, good stability and high refractive index. The first lens film is made of a material with a higher refractive index, which can increase the refraction angle of light, that is, enhance the divergence ability of the first lens film. At the same time, the curvature radius and thickness of the first lens film can be smaller.

[0066] It should be noted that the material for making the first lens film can be inorganic materials such as silicon oxide or silicon nitride, but is not limited to this. The material for making the first lens film can also be organic polymer materials such as polyimide, acrylic resin, epoxy resin, etc., depending on the specific situation.

[0067] Example 2

[0068] The difference between the second embodiment and the first embodiment is that the flat panel detector further includes a compensation substrate 200 .

[0069] See also Figure 2 As shown, the compensation substrate 200 is formed on the side of the array substrate 300 close to the diffusion substrate 100. The compensation substrate 200 contacts the array substrate 300 and is spaced apart from the diffusion substrate 100. The orthographic projection of the compensation substrate 200 on the array substrate 300 overlaps with the array substrate 300.

[0070] The compensation substrate 200 includes a second base substrate 210 and a light-gathering film 220. The second base substrate 210 is disposed on the side of the array substrate 300 close to the diffusion substrate 100. The light-gathering film 220 is formed on the side of the second base substrate 210 close to the diffusion substrate 100. The light-gathering film 220 is used to make the visible light irradiate the array substrate 300 vertically. Figure 2 As shown, Figure 2 The middle arrow represents the light.

[0071] Since the diffusion substrate 100 evenly disperses the visible light converted by the scintillator 120, the visible light will illuminate the array substrate 300 at an angle. The compensation substrate 200 is arranged on the side of the array substrate 300 close to the diffusion substrate 100. By compensating the light path through the compensation substrate 200, the visible light can be vertically illuminated to the array substrate 300, thereby improving the sensing sensitivity of the photodiode.

[0072] In some embodiments, the focusing film 220 includes a second lens film, which is convex outward on the side away from the second base substrate 210 to form a convex lens. The closer the second lens film is to the center, the greater the convex height. In other words, the entire second lens film is a convex lens.

[0073] The focusing film 220 is a second lens film. The second lens film bulges outwards on a side away from the second base substrate 210 to form a convex lens. The focusing film 220 has a simpler structure and can reduce the manufacturing cost of the flat panel detector.

[0074] It should be noted that the second lens film bulges outward on the side away from the second base substrate 210 to form a convex lens, and the entire second lens film is a convex lens, but is not limited to this. The second lens film may also include a plurality of micro convex lens structures arranged in an array, depending on the specific situation.

[0075] In some embodiments, the material of the second lens film is the same as the material of the first lens film, and the refractive index of the material of the second lens film is the same as the refractive index of the material of the first lens film.

[0076] The second lens film and the first lens film are made of a material with the same refractive index, which adjusts the optical path of the visible light and makes it easier for the visible light to vertically illuminate the array substrate 300.

[0077] See also Figure 3 As shown, the array substrate 300 includes a third base substrate 310 and a detection function layer, and the detection function layer includes a first metal layer 320, a gate insulation layer 391, an active layer 330, a second metal layer 340, a first passivation layer 392, a third metal layer 350, a photoelectric conversion layer 360, a transparent conductive layer 370, a second passivation layer 393, a first flat layer 394, a fourth metal layer 380, a third passivation layer 395 and a second flat layer 396.

[0078] A first metal layer 320 is formed on a side of the third substrate 310 and may include a gate. A gate insulating layer 391 is formed on a side of the first metal layer 320 away from the third substrate 310. An active layer 330 is formed on a side of the gate insulating layer 391 away from the third substrate 310. The orthographic projection of the active layer 330 on the third substrate 310 overlaps with or is centered with the gate. A second metal layer 340 is formed on a side of the active layer 330 away from the third substrate 310 and includes a drain electrode 341 and a source electrode 342 spaced apart. A first passivation layer 392 is formed on a side of the second metal layer 340 away from the third substrate 310. The gate, active layer 330, drain electrode 341, and source electrode 342 constitute a thin film transistor.

[0079] The third metal layer 350 is formed on the side of the first passivation layer 392 away from the third substrate 310. The third metal layer 350 is connected to the source electrode 342 through a via that penetrates the first passivation layer 392. The photoelectric conversion layer 360 can have a PN structure or a PIN structure. Specifically, the photoelectric conversion layer 360 with a PIN structure includes an N-type doped semiconductor layer (N), an undoped intrinsic semiconductor layer (I), and a P-type doped semiconductor layer (P) stacked in sequence; the photoelectric conversion layer 360 with a PN structure does not include the intrinsic semiconductor layer (I). The transparent conductive layer 370 is formed on the side of the photoelectric conversion layer 360 away from the third substrate 310. The third metal layer 350, the photoelectric conversion layer 360, and the transparent conductive layer 370 constitute a photodiode, with the third metal layer 350 serving as the lower electrode of the photodiode and the transparent conductive layer 370 serving as the upper electrode of the photodiode.

[0080] A second passivation layer 393 is formed on the side of the transparent conductive layer 370, the third metal layer 350, and the first passivation layer 392 away from the third substrate 310. A first planarization layer 394 is formed on the side of the second passivation layer 393 away from the third substrate 310. A fourth metal layer 380 is formed on the side of the first planarization layer 394 away from the third substrate 310. The fourth metal layer 380 includes a bias electrode 381 and a light shielding portion 382. The bias electrode 381 is connected to the transparent conductive layer 370 via a via extending through the first planarization layer 394 and the second passivation layer 393. The light shielding portion 382 is located above the thin-film transistor and can at least shield the active layer 330 between the drain electrode 341 and the source electrode 342. A third passivation layer 395 is formed on the side of the fourth metal layer 380 away from the third substrate 310. A second planarization layer 396 is formed on the side of the third passivation layer 395 away from the third substrate 310.

[0081] The array substrate 300 further includes a light-gathering film 220, which is formed on a side of the second planar layer 396 away from the third base substrate 310. The light-gathering film 220 is used to allow visible light to irradiate the array substrate 300 vertically.

[0082] It should be noted that the light-concentrating film 220 can be formed on the side of the second flat layer 396 away from the third base substrate 310 , but is not limited thereto. The second flat layer 396 can also be made into the light-concentrating film 220 , depending on the specific situation.

[0083] The light-concentrating film 220 is formed on the side of the detection function layer away from the third base substrate 310 , which reduces one base substrate and can reduce the manufacturing cost of the flat panel detector.

[0084] Example 3

[0085] This application also provides a method for manufacturing a flat panel detector, which is used to manufacture the flat panel detector disclosed in Example 1 or Example 2. Figures 4 to 7 As shown, the manufacturing method of the flat panel detector includes:

[0086] S100: manufacturing an array substrate 300;

[0087] S200: forming a scintillator 120 and a diffusion film 130 on opposite sides of a first base substrate 110 to obtain a diffusion substrate 100, wherein the diffusion film 130 includes a first lens film, and a side of the first lens film away from the first base substrate 110 is concave inward to form a concave lens;

[0088] S300 : Mounting the diffusion substrate 100 on one side of the array substrate 300 , with the diffusion film surface 130 facing the array substrate 300 , and forming a gap between the diffusion film 130 and the array substrate 300 .

[0089] Since the diffusion film 130 can evenly disperse the visible light converted by the scintillator 120, the area of ​​the array substrate 300 can be larger than the area of ​​the scintillator 120, and the minimum number and spacing of the detection units of the array substrate 300 and the photosensitive area of ​​the photodiode can be increased, that is, the resolution and resolution of the flat panel detector can be improved.

[0090] In some embodiments, a method of forming a first lens film includes:

[0091] A first transparent material layer 131 and a first photoresist layer 140 are sequentially formed on one side of the first base substrate 110;

[0092] The first photoresist layer 140 is exposed using a mask 400 with a gradient transmittance, and then a portion of the first photoresist layer 140 is removed by development, so that the first photoresist layer 140 forms an inwardly concave curved surface on the side away from the first base substrate 110;

[0093] The remaining first photoresist layer 140 and a portion of the first transparent material layer 131 are removed by etching to form a first lens film.

[0094] The first transparent material layer 131 can be made of inorganic materials such as silicon oxide and silicon nitride, and the first photoresist layer 140 can be made of positive photoresist. The transmittance of the center area of ​​the transmittance gradient mask 400 is the highest, and the transmittance of the area closer to the edge of the mask 400 is smaller. The first photoresist layer 140 can be exposed by a parallel light source, such as Figure 5 As shown, Figure 5 The middle arrow represents light. It should be noted that a point light source can also be used to expose the first photoresist layer 140. Since the first photoresist layer 140 is made of positive photoresist, the stronger the exposure energy to the positive photoresist, the greater the thickness of the film removed by development. Therefore, a concave curved surface is formed on the side of the first photoresist layer 140 away from the first base substrate 110. Then, by simultaneously etching the first photoresist layer 140 and the first transparent material layer 131, the first photoresist layer 140 can be completely removed and the first transparent material layer 131 can be partially removed. The concave curved surface on the first photoresist layer 140 is transferred to the first transparent material layer 131 to form a first lens film.

[0095] Inorganic materials such as silicon oxide and silicon nitride have high light transmittance, good stability and high refractive index. The first lens film is made of a material with a higher refractive index, which can increase the refraction angle of light, that is, enhance the divergence ability of the first lens film. At the same time, the curvature radius and thickness of the first lens film can be smaller.

[0096] It should be noted that the first photoresist layer 140 can be made of, but is not limited to, positive photoresist. The first photoresist layer 140 can also be made of negative photoresist, depending on the specific circumstances. When the first photoresist layer 140 is made of negative photoresist, the transmittance of the center region of the mask 400 with a gradient transmittance is the lowest, and the transmittance increases as the area closer to the edge of the mask 400. Because the first photoresist layer 140 is made of negative photoresist, the stronger the exposure energy to the negative photoresist, the smaller the thickness of the film removed by development. Therefore, a concave curved surface can also be formed on the side of the first photoresist layer 140 away from the first base substrate 110.

[0097] In some embodiments, the flat panel detector further includes a compensation substrate 200, the compensation substrate 200 includes a second base substrate 210 and a light-gathering film 220, and the light-gathering film 220 includes a second lens film. The method of forming the second lens film includes:

[0098] A second transparent material layer 221 and a second photoresist layer 230 are sequentially formed on one side of the second base substrate 210;

[0099] The second photoresist layer 230 is exposed using a mask 400 with a gradient transmittance, and then a portion of the second photoresist layer 230 is removed by development, so that the second photoresist layer 230 forms an outwardly convex curved surface on the side away from the second base substrate 210;

[0100] The remaining second photoresist layer 230 and a portion of the second transparent material layer 221 are removed by etching to form a second lens film.

[0101] The second transparent material layer 221 can be made of inorganic materials such as silicon oxide and silicon nitride, and the second photoresist layer 230 can be made of positive or negative photoresist. A parallel light source can be used to expose the second photoresist layer 230, but this is not limited to this. A point light source can also be used to expose the first photoresist layer 140, depending on the specific situation. The principles for making the second lens film are similar to those for making the first lens film, so the detailed production process will not be repeated here.

[0102] Inorganic materials such as silicon oxide and silicon nitride have high light transmittance, good stability and high refractive index. The second lens film is made of a material with a higher refractive index, which can increase the refraction angle of light, that is, enhance the focusing ability of the second lens film. At the same time, the curvature radius and thickness of the second lens film can be smaller.

[0103] In some embodiments, the first and second lens films are formed using the same photomask 400. The first and second photoresist layers 140 and 230 are formed using a positive photoresist, and the first and second photoresist layers 230 are formed using a negative photoresist. When the first and second lens films are formed using the same photomask 400, both the first and second photoresist layers 140 and 230 can be exposed using a point light source. When the second photoresist layer 230 is exposed, the distance between the photomask 400 and the second photoresist layer 230 is greater than the distance between the photomask 400 and the first photoresist layer 140 when the first photoresist layer 140 is exposed.

[0104] The same mask 400 is used to form the first lens film and the second lens film, which can reduce the manufacturing cost of the flat panel detector.

[0105] The terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature identified with "first," "second," etc., may explicitly or implicitly include one or more of such features. Throughout the description of this application, "plurality" means two or more, unless otherwise specifically defined.

[0106] In this application, unless otherwise specified or limited, terms such as "assembly" and "connection" should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection; direct connection, or indirect connection through an intermediate medium; internal communication between two components, or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0107] In the description of this specification, the reference terms "some embodiments", "exemplarily", etc. mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.

[0108] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application. Therefore, any changes or modifications made in accordance with the claims and description of the present application should fall within the scope of the patent application.

Claims

1. A flat panel detector, comprising an array substrate, characterized in that: The flat panel detector further includes a diffusion substrate, which is arranged on one side of the array substrate, is spaced apart from the array substrate, and has an orthographic projection of the diffusion substrate on the array substrate located within the array substrate. The diffusion substrate includes: a first substrate; a scintillator, formed on a side of the first substrate away from the array substrate, and configured to convert X-rays into visible light; A diffusion film is formed on a side of the first substrate close to the array substrate, and is used to uniformly disperse the visible light converted by the scintillator.

2. The flat panel detector according to claim 1, wherein: The diffusion film includes a first lens film, and the first lens film is concave inwardly at a side away from the first base substrate to form a concave lens.

3. The flat panel detector according to claim 2, wherein: The first lens film is made of a material including silicon oxide or silicon nitride.

4. The flat panel detector according to claim 1, wherein: The flat panel detector further includes a compensation substrate, which is formed on a side of the array substrate close to the diffusion substrate, the compensation substrate and the diffusion substrate are spaced apart, and an orthographic projection of the compensation substrate on the array substrate coincides with the array substrate; The compensation substrate includes a second base substrate and a light-gathering film. The second base substrate is arranged on a side of the array substrate close to the diffusion substrate. The light-gathering film is formed on a side of the second base substrate close to the diffusion substrate. The light-gathering film is used to make the visible light irradiate the array substrate vertically.

5. The flat panel detector according to claim 4, characterized in that: The diffusion film includes a first lens film, wherein the first lens film is concave inwardly on a side away from the first substrate to form a concave lens; The light-concentrating film includes a second lens film, and the second lens film is convex outwardly away from the second base substrate to form a convex lens.

6. The flat panel detector according to claim 5, characterized in that: The refractive index of the material of which the second lens film is made is the same as the refractive index of the material of which the first lens film is made.

7. The flat panel detector according to claim 1, wherein: The array substrate includes a third base substrate, a detection function layer and a focusing film. The detection function layer and the focusing film are sequentially formed on one side of the third base substrate. The focusing film is spaced apart from the diffusion substrate. The focusing film is used to allow the visible light to vertically irradiate the detection function layer.

8. A method for manufacturing a flat panel detector, characterized in that: The manufacturing method of the flat panel detector is used to manufacture the flat panel detector according to any one of claims 1 to 7, and the manufacturing method of the flat panel detector comprises: manufacturing an array substrate; A scintillator and a diffusion film are formed on opposite sides of a first base substrate to prepare a diffusion substrate, wherein the diffusion film includes a first lens film, and the first lens film is concave inwardly on a side away from the first base substrate to form a concave lens; Mounting the diffusion substrate on one side of the array substrate so that the diffusion film faces the array substrate and a gap is formed between the diffusion film and the array substrate; The method of forming the first lens film includes: forming a first transparent material layer and a first photoresist layer in sequence on one side of the first base substrate; exposing the first photoresist layer using a mask with a gradient transmittance, and then developing and removing a portion of the first photoresist layer, so that a side of the first photoresist layer away from the first base substrate forms an inwardly concave curved surface; The remaining first photoresist layer and a portion of the first transparent material layer are removed by etching to form the first lens film.

9. The method for manufacturing a flat panel detector according to claim 8, wherein: The flat panel detector further includes a compensation substrate, the compensation substrate being formed on a side of the array substrate close to the diffusion substrate, the compensation substrate being spaced apart from the diffusion substrate, and an orthographic projection of the compensation substrate on the array substrate coinciding with the array substrate, the compensation substrate including a second base substrate and a light-concentrating film, the second base substrate being provided on a side of the array substrate close to the diffusion substrate, the light-concentrating film being formed on a side of the second base substrate close to the diffusion substrate, the light-concentrating film being used to allow the visible light to vertically illuminate the array substrate, the light-concentrating film including a second lens film, the second lens film being convex outwardly on a side away from the second base substrate to form a convex lens; The method of forming the second lens film includes: forming a second transparent material layer and a second photoresist layer in sequence on one side of the second base substrate; exposing the second photoresist layer using a mask with a gradient transmittance, and then developing and removing a portion of the second photoresist layer to form an outwardly convex curved surface on a side of the second photoresist layer away from the second base substrate; The remaining second photoresist layer and a portion of the second transparent material layer are removed by etching to form the second lens film.

10. The method for manufacturing a flat panel detector according to claim 9, wherein: The first lens film and the second lens film are formed using the same photomask. The first photoresist layer and the second photoresist layer: one is made of positive photoresist and the other is made of negative photoresist.

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