Amorphous silicon photodiode module

Abstract

The present invention provides an amorphous silicon photodiode module, comprising: a TFT glass substrate, including a first surface and an opposite second surface; a first amorphous silicon photodiode, having a first transparent upper electrode and a first transparent lower electrode, wherein the first amorphous silicon photodiode is fixed to the first surface of the TFT glass substrate through the first transparent lower electrode, and is connected to a second amorphous silicon photodiode on the second surface of the TFT glass substrate through the first transparent lower electrode. When preparing an amorphous silicon photodiode based on a TFT glass substrate, the electrode adjacent to the TFT glass substrate is changed into a transparent electrode, and the front amorphous silicon photodiode cannot completely absorb the visible light generated by the scintillator, and the remaining light can penetrate the transparent electrode and reach the back of the TFT glass substrate, and can be absorbed by the amorphous silicon photodiode on the back to enhance the signal amplitude.

Description

Technical Field

[0001] The invention relates to the field of nuclear radiation detection and nuclear technology application, and in particular to an amorphous silicon photodiode module capable of enhancing signal amplitude. Background Art

[0002] The technology widely used in the field of radiation detection and imaging mainly generates visible light by irradiating the scintillator pixel array with radiation, converting it into an electrical signal through the photodiode (PD), and then collecting and transmitting data through the electronic system, and processing it by the image reconstruction algorithm to display the test image. These technologies are used in medical equipment, safety testing equipment, industrial non-destructive testing equipment, food and agricultural product safety sorting systems, and other radiation detection systems.

[0003] The structure of the imaging module is usually a cut and packaged scintillator pixel array, which is bonded and coupled with the photodiode pixel array, and the generated electrical signal is input into the subsequent electronic acquisition system. The photodiode is divided into traditional single-crystal silicon photodiodes and amorphous silicon photodiodes based on TFT glass. The former has a thick photosensitive layer that can completely absorb the visible light generated by the scintillating material and generate a large signal; while the amorphous silicon photodiode prepared on TFT glass can only reach a maximum thickness of 2μm, generally around 1.2μm, and has severe absorption attenuation for light longer than 700nm.

[0004] When applied to radiation imaging, such as TFT-based flat-panel detectors and detector modules with only amorphous silicon photodiode arrays, due to the limited light absorption capacity of amorphous photodiodes, the light signal of amorphous silicon is smaller than that of single-crystalline silicon for scintillator materials of the same thickness, which will seriously affect the clarity of the image.

[0005] Based on the above, it is necessary to provide an amorphous silicon photodiode module that can effectively solve the problem that the photosensitive layer thickness of the amorphous silicon photodiode based on TFT glass is limited, the excited photoelectric conversion signal is small, and the subsequent image quality is affected by the image. Summary of the invention

[0006] In view of the above-mentioned shortcomings of the prior art, the purpose of the present invention is to provide an amorphous silicon photodiode module to solve the problem that the photosensitive layer thickness of the amorphous silicon photodiode based on TFT glass in the prior art is limited, the excited photoelectric conversion signal is small, and the subsequent image quality is affected by the image.

[0007] To achieve the above-mentioned purpose and other related purposes, the present invention provides an amorphous silicon photodiode module, which includes: a TFT glass substrate, including a first surface and a second surface opposite to the first surface; a first amorphous silicon photodiode, having a first transparent upper electrode and a first transparent lower electrode, and the first amorphous silicon photodiode is fixed to the first surface of the TFT glass substrate through the first transparent lower electrode.

[0008] Preferably, the amorphous silicon photodiode module further includes a first scintillator layer, and the first scintillator layer is located on the first transparent upper electrode of the first amorphous silicon photodiode.

[0009] Preferably, the amorphous silicon photodiode module further includes a second scintillator layer, and the second scintillator layer is located on the second surface of the TFT glass substrate.

[0010] Preferably, the TFT glass substrate and the first amorphous silicon photodiode form a module unit, and the amorphous silicon photodiode module includes at least two stacked module units, and two adjacent module units are electrically connected.

[0011] Preferably, the stacking method includes: the TFT glass substrate of the upper module unit is connected to the first amorphous silicon photodiode of the lower module unit.

[0012] Preferably, the amorphous silicon photodiode module further includes a first scintillator layer, and the first scintillator layer is located on the first transparent upper electrode of the uppermost amorphous silicon photodiode.

[0013] Preferably, the stacking method includes: the TFT glass substrate of the upper module unit is connected to the TFT glass substrate of the lower module unit.

[0014] Preferably, the amorphous silicon photodiode module further includes a first scintillator layer and a second scintillator layer, and the first scintillator layer and the second scintillator layer are respectively located on surfaces of the first transparent upper electrodes of two oppositely spaced first amorphous silicon photodiodes.

[0015] Preferably, the first scintillator layer and the second scintillator layer include one selected from the group consisting of a GOS ceramic scintillator layer, a NaI scintillator layer, a CsI scintillator layer, a laBr3 scintillator layer and a CdWO4 scintillator layer.

[0016] Preferably, it also includes a second amorphous silicon photodiode, which has a second transparent upper electrode and a second lower electrode. The second amorphous silicon photodiode is fixed to the second surface of the TFT glass substrate through the second transparent upper electrode and is electrically connected to the first amorphous silicon photodiode. After the light is absorbed by the first amorphous silicon photodiode, the remaining light passes through the first transparent lower electrode of the first amorphous silicon photodiode and the TFT glass substrate and is absorbed by the second amorphous silicon photodiode to increase the signal amplitude of the amorphous silicon photodiode module.

[0017] Preferably, the second amorphous silicon photodiode is connected in series with the first amorphous silicon photodiode to reduce a large capacitance between the first amorphous silicon photodiode and the second amorphous silicon photodiode.

[0018] Preferably, the second amorphous silicon photodiode is connected in parallel with the first amorphous silicon photodiode to increase signal amplitude and reduce noise.

[0019] Preferably, the second lower electrode of the second amorphous silicon photodiode is a second non-transparent lower electrode.

[0020] Preferably, the amorphous silicon photodiode module further includes a first scintillator layer, and the first scintillator layer is located on the first transparent upper electrode of the uppermost amorphous silicon photodiode.

[0021] Preferably, the second lower electrode of the second amorphous silicon photodiode is a second transparent lower electrode, and the amorphous silicon photodiode module further includes a second scintillator layer, and the second scintillator layer is located on the surface of the second transparent lower electrode.

[0022] Preferably, the second lower electrode of the second amorphous silicon photodiode is a second transparent lower electrode, and the TFT glass substrate, the first amorphous silicon photodiode and the second amorphous silicon photodiode form a module unit, and the amorphous silicon photodiode module includes at least two stacked module units, wherein the second transparent lower electrode of the second amorphous silicon photodiode of the upper module unit is connected to the first transparent upper electrode of the first amorphous silicon photodiode of the lower module unit.

[0023] Preferably, the first transparent lower electrode comprises one of a fully transparent electrode, a combination of a fully transparent electrode and a grid-shaped metal electrode, and a combination of a fully transparent electrode and a dot-shaped metal electrode.

[0024] As described above, the amorphous silicon photodiode module of the present invention has the following beneficial effects:

[0025] When preparing an amorphous silicon photodiode based on TFT glass, the present invention changes the electrode adjacent to the TFT glass into a transparent electrode, and the front amorphous silicon photodiode cannot completely absorb the visible light generated by the scintillator, and the remaining light can penetrate the transparent electrode and reach the back of the glass, and be absorbed by the amorphous silicon photodiode on the back, so that the generated signal is enhanced. At the same time, the front and back amorphous silicon photodiodes can be connected in series through metal vias, so that the large capacitance brought by the thin amorphous silicon photodiode is reduced, or two amorphous silicon photodiodes are connected in parallel, thereby improving light absorption, amplifying the signal amplitude, reducing noise, and improving system performance.

[0026] The present invention can also directly prepare a new scintillator array on the glass back side of the amorphous silicon photodiode with a transparent electrode to absorb more radiation. The generated visible light can also enter the amorphous silicon photodiode on the front side through the transparent electrode to increase the signal amplitude.

[0027] The present invention can be applied to a dual-energy or single-energy detector module in a radiation imaging system, and can also be applied to a TFT type flat panel detector, thereby reducing costs while ensuring or improving system performance and expanding the application field. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 to Figure 4 It is a schematic structural diagram of the amorphous silicon photodiode module in Embodiment 1 of the present invention.

[0029] Figure 5 It is a schematic structural diagram of an amorphous silicon photodiode module in Embodiment 2 of the present invention.

[0030] Figure 6-7 It is a schematic structural diagram of the amorphous silicon photodiode module in Example 3 of the present invention.

[0031] Figure 8 to Figure 10 It is a schematic structural diagram of an amorphous silicon photodiode module in Embodiment 4 of the present invention.

[0032] Fig.11 It is a schematic structural diagram of an amorphous silicon photodiode module in Embodiment 5 of the present invention.

[0033] Fig.12 It is a schematic structural diagram of an amorphous silicon photodiode module in Embodiment 6 of the present invention.

[0034] Figure 13-14 Shown is a schematic structural diagram of an amorphous silicon photodiode module in Example 7 of the present invention.

[0035] Component number description

[0036] 101 TFT glass substrate

[0037] 102 The first amorphous silicon photodiode

[0038] 103 first transparent upper electrode

[0039] 104 first transparent lower electrode

[0040] 1041 Fully transparent electrode

[0041] 1042 Grid Metal Electrode

[0042] 1043 Point Metal Electrode

[0043] 105 First scintillator layer

[0044] 106 Second scintillator layer

[0045] 202 Second amorphous silicon photodiode

[0046] 203 second transparent upper electrode

[0047] 204 second transparent lower electrode

[0048] 207 second non-transparent lower electrode DETAILED DESCRIPTION

[0049] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0050] See also Figure 1 to Figure 14 It should be noted that the illustrations provided in this embodiment are only used to illustrate the basic concept of the present invention in a schematic manner, and the illustrations only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0051] Example 1

[0052] like Figure 1 to Figure 4As shown, this embodiment provides an amorphous silicon photodiode module, which includes: a TFT glass substrate 101, including a first surface and a second surface opposite to the first surface, the first surface of the TFT glass substrate 101 is suitable for preparing a thin film transistor (TFT); a first amorphous silicon photodiode 102, having a first transparent upper electrode 103 and a first transparent lower electrode 104, the first amorphous silicon photodiode 102 is fixed to the first surface of the TFT glass substrate 101 through the first transparent lower electrode 104.

[0053] like Figure 2 to Figure 4 As shown, the first transparent lower electrode 104 may be a fully transparent electrode 1041. Figure 2 As shown, the use of the fully transparent electrode 1041 can effectively increase the light transmission rate; the first transparent lower electrode 104 can also be a combination of the fully transparent electrode 1041 and the grid-shaped metal electrode 1042, such as Figure 3 As shown, the first transparent lower electrode 104 may also be a combination of a fully transparent electrode 1041 and a dot-shaped metal electrode 1043. Figure 4 As shown, the combination of the fully transparent electrode 1041 and the metal electrode can improve the mechanical strength of the electrode, reduce resistance, and reduce signal loss.

[0054] The first amorphous silicon photodiode 102 of the present embodiment adopts a transparent upper electrode and a transparent lower electrode, so that light can be incident on the first amorphous silicon photodiode 102 from both the upper and lower surfaces, which can effectively increase the signal amplitude.

[0055] Example 2

[0056] like Figure 5 As shown, this embodiment provides an amorphous silicon photodiode module, which includes: a TFT glass substrate 101, including a first surface and a second surface opposite to the first surface; a first amorphous silicon photodiode 102, having a first transparent upper electrode 103 and a first transparent lower electrode 104, and the first amorphous silicon photodiode 102 is fixed to the first surface of the TFT glass substrate 101 through the first transparent lower electrode 104.

[0057] The amorphous silicon photodiode module further includes a first scintillator layer 106 , which is located on the first transparent upper electrode 103 of the first amorphous silicon photodiode 102 . The amorphous silicon photodiode module further includes a second scintillator layer 106 , which is located on the second surface of the TFT glass substrate 101 .

[0058] The present invention directly prepares a new scintillator array on the back of the glass of the amorphous silicon photodiode with a transparent electrode, which can absorb more radiation, and the generated visible light can enter the amorphous silicon photodiode on the front through the transparent electrode, thereby increasing the signal amplitude. For example, the first scintillator layer 106 and the second scintillator layer 106 can be one of the groups consisting of a GOS ceramic scintillator layer, a NaI scintillator layer, a CsI scintillator layer, a laBr3 scintillator layer and a CdWO4 scintillator layer. In this embodiment, the first scintillator layer 106 and the second scintillator layer 106 can be a GOS ceramic scintillator layer. Due to the absorption of light by the GOS ceramic scintillator layer itself, the GOS thickness limit is less than 2 mm, and 1.5 mm is commonly used, otherwise the self-absorption problem of light is serious. In this embodiment, the GOS ceramic scintillator layer can be divided into two parts, each accounting for half of the original thickness, and respectively pasted on the front and back sides of the TFT glass substrate 101 of the amorphous silicon photodiode pixel with a transparent electrode, so that the amorphous silicon photodiode can absorb the light entering from both sides, improve the radiation detection efficiency, and increase the signal amplitude.

[0059] Example 3

[0060] like Figure 6-7 As shown, this embodiment provides an amorphous silicon photodiode module, the amorphous silicon photodiode module comprising: a TFT glass substrate 101, including a first surface and a second surface opposite to the first surface; a first amorphous silicon photodiode 102, having a first transparent upper electrode 103 and a first transparent lower electrode 104, the first amorphous silicon photodiode 102 being fixed on the first surface of the TFT glass substrate 101 through the first transparent lower electrode 104. The TFT glass substrate 101 and the first amorphous silicon photodiode 102 form a module unit, the amorphous silicon photodiode module comprises at least two stacked module units, and two adjacent module units are electrically connected through the conductive through-holes in the TFT glass substrate 101. The stacking method is as follows: the TFT glass substrate 101 of the upper module unit is connected to the first amorphous silicon photodiode 102 of the lower module unit.

[0061] Of course, the amorphous silicon photodiode module may also include a first scintillator layer 106, which is located on the first transparent upper electrode 103 of the first amorphous silicon photodiode 102 at the top layer. It may also include a second scintillator layer 106, which is located on the lower surface of the TFT glass substrate 101 at the bottom layer, such as Figure 7 described.

[0062] Example 4

[0063] like Figure 8 to Figure 10 As shown, this embodiment provides an amorphous silicon photodiode module, the amorphous silicon photodiode module comprising: a TFT glass substrate 101, comprising a first surface and a second surface opposite to the first surface; a first amorphous silicon photodiode 102, having a first transparent upper electrode 103 and a first transparent lower electrode 104, the first amorphous silicon photodiode 102 being fixed to the first surface of the TFT glass substrate 101 through the first transparent lower electrode 104. A module unit is formed by the TFT glass substrate 101 and the first amorphous silicon photodiode 102, the amorphous silicon photodiode module comprising at least two stacked module units, two adjacent module units being electrically connected through conductive through holes in the TFT glass substrate 101. The stacking method is as follows: the TFT glass substrate 101 of the upper module unit is connected to the TFT glass substrate 101 of the lower module unit, such as Figure 8 shown.

[0064] like Figure 9-10 As shown, the amorphous silicon photodiode module further includes a first scintillator layer 106, such as Fig. 9 As shown, or comprising a first scintillator layer 106 and a second scintillator layer 106 at the same time, the first scintillator layer 106 and the second scintillator layer 106 are respectively located on the surface of the first transparent upper electrode 103 of two first amorphous silicon photodiodes 102 which are separated from each other, as shown Fig.10 shown.

[0065] As an example, the first scintillator layer 106 and the second scintillator layer 106 may be one of the group consisting of a GOS ceramic scintillator layer, a NaI scintillator layer, a CsI scintillator layer, a laBr3 scintillator layer and a CdWO4 scintillator layer. In this embodiment, the first scintillator layer 106 and the second scintillator layer 106 may be a GOS ceramic scintillator layer. Due to the absorption of light by the GOS ceramic scintillator layer itself, the GOS thickness limit is below 2 mm, and 1.5 mm is commonly used, otherwise the self-absorption of light is serious. In this embodiment, the GOS ceramic scintillator layer can be divided into two parts, each accounting for half of the original thickness, and respectively pasted on the amorphous silicon photodiode with transparent electrodes on the front and back sides of the TFT glass substrate 101, so that the amorphous silicon photodiode can absorb light entering from both sides, improve the radiation detection efficiency, and increase the signal amplitude.

[0066] Example 5

[0067] like Fig.11As shown, this embodiment provides an amorphous silicon photodiode module, which includes: a TFT glass substrate 101, including a first surface and a second surface opposite to the first surface; a first amorphous silicon photodiode 102, having a first transparent upper electrode 103 and a first transparent lower electrode 104, and the first amorphous silicon photodiode 102 is fixed to the first surface of the TFT glass substrate 101 through the first transparent lower electrode 104.

[0068] The amorphous silicon photodiode module also includes a second amorphous silicon photodiode 202, which has a second transparent upper electrode 203 and a second lower electrode. The second amorphous silicon photodiode 202 is fixed to the second surface of the TFT glass substrate 101 through the second transparent upper electrode 203, and is electrically connected to the first amorphous silicon photodiode 102 through a conductive through hole in the TFT glass substrate 101. After the light is absorbed by the first amorphous silicon photodiode 102, the remaining light passes through the first transparent lower electrode 104 of the first amorphous silicon photodiode 102 and the TFT glass substrate 101 and is absorbed by the second amorphous silicon photodiode 202, so as to increase the signal amplitude of the amorphous silicon photodiode module.

[0069] As an example, the second amorphous silicon photodiode 202 is connected in series with the first amorphous silicon photodiode 102 through the conductive via to reduce the large capacitance between the first amorphous silicon photodiode 102 and the second amorphous silicon photodiode 202 .

[0070] In another embodiment, the second amorphous silicon photodiode 202 may also be connected in parallel with the first amorphous silicon photodiode 102 through the conductive via to increase the signal amplitude and reduce noise.

[0071] In this embodiment, the amorphous silicon photodiode module further includes a first scintillator layer 106, and the first scintillator layer 106 is located on the first transparent upper electrode 103 of the first amorphous silicon photodiode 102 at the top layer. In addition, the second lower electrode of the second amorphous silicon photodiode 202 is a second non-transparent lower electrode 207. Fig.11 shown.

[0072] When preparing an amorphous silicon photodiode based on TFT glass, the present invention changes the electrode adjacent to the TFT glass into a transparent electrode, and the front amorphous silicon photodiode cannot completely absorb the visible light generated by the scintillator, and the remaining light can penetrate the transparent electrode and reach the back of the glass to be absorbed by the amorphous silicon photodiode on the back, so that the generated signal is enhanced. At the same time, the front and back amorphous silicon photodiodes can be connected in series through metal vias, so that the large capacitance brought by the thin amorphous silicon photodiode is reduced, or two amorphous silicon photodiodes are connected in parallel, thereby improving light absorption, amplifying the signal amplitude, reducing noise, and improving system performance.

[0073] It should be noted that in other embodiments, the through hole may not be prepared in the TFT glass substrate 101, but the signal may be led out to connect the signals of the first amorphous silicon photodiode 102 and the second amorphous silicon photodiode 202 together before entering the front-end readout chip.

[0074] Example 6

[0075] like Fig.12 As shown, this embodiment provides an amorphous silicon photodiode module, which includes: a TFT glass substrate 101, including a first surface and a second surface opposite to the first surface; a first amorphous silicon photodiode 102, having a first transparent upper electrode 103 and a first transparent lower electrode 104, and the first amorphous silicon photodiode 102 is fixed to the first surface of the TFT glass substrate 101 through the first transparent lower electrode 104.

[0076] The amorphous silicon photodiode module also includes a second amorphous silicon photodiode 202, which has a second transparent upper electrode 203 and a second lower electrode. The second amorphous silicon photodiode 202 is fixed to the second surface of the TFT glass substrate 101 through the second transparent upper electrode 203, and is electrically connected to the first amorphous silicon photodiode 102 through a conductive through hole in the TFT glass substrate 101. After the light is absorbed by the first amorphous silicon photodiode 102, the remaining light passes through the first transparent lower electrode 104 of the first amorphous silicon photodiode 102 and the TFT glass substrate 101 and is absorbed by the second amorphous silicon photodiode 202, so as to increase the signal amplitude of the amorphous silicon photodiode module.

[0077] As an example, the second amorphous silicon photodiode 202 is connected in series with the first amorphous silicon photodiode 102 through the conductive via to reduce the large capacitance between the first amorphous silicon photodiode 102 and the second amorphous silicon photodiode 202 .

[0078] In another embodiment, the second amorphous silicon photodiode 202 may also be connected in parallel with the first amorphous silicon photodiode 102 through the conductive via to increase the signal amplitude and reduce noise.

[0079] In this embodiment, the second lower electrode of the second amorphous silicon photodiode 202 is a second transparent lower electrode 204, and the amorphous silicon photodiode module further includes a first scintillator layer 106 and a second scintillator layer 106, wherein the first scintillator layer 106 is located on the first transparent upper electrode 103 of the first amorphous silicon photodiode 102 at the uppermost layer, and the second scintillator layer 106 is located on the surface of the second transparent lower electrode 204. Fig.12 shown.

[0080] It should be noted that in other embodiments, the through hole may not be prepared in the TFT glass substrate 101, but the signal may be led out to connect the signals of the first amorphous silicon photodiode 102 and the second amorphous silicon photodiode 202 together before entering the front-end readout chip.

[0081] Example 7

[0082] like Figure 13-14 As shown, this embodiment provides an amorphous silicon photodiode module, which includes: a TFT glass substrate 101, including a first surface and a second surface opposite to the first surface; a first amorphous silicon photodiode 102, having a first transparent upper electrode 103 and a first transparent lower electrode 104, and the first amorphous silicon photodiode 102 is fixed to the first surface of the TFT glass substrate 101 through the first transparent lower electrode 104.

[0083] The amorphous silicon photodiode module also includes a second amorphous silicon photodiode 202, which has a second transparent upper electrode 203 and a second lower electrode. The second amorphous silicon photodiode 202 is fixed to the second surface of the TFT glass substrate 101 through the second transparent upper electrode 203, and is electrically connected to the first amorphous silicon photodiode 102 through a conductive through hole in the TFT glass substrate 101. After the light is absorbed by the first amorphous silicon photodiode 102, the remaining light passes through the first transparent lower electrode 104 of the first amorphous silicon photodiode 102 and the TFT glass substrate 101 and is absorbed by the second amorphous silicon photodiode 202, so as to increase the signal amplitude of the amorphous silicon photodiode module.

[0084] As an example, the second amorphous silicon photodiode 202 is connected in series with the first amorphous silicon photodiode 102 through the conductive via to reduce the large capacitance between the first amorphous silicon photodiode 102 and the second amorphous silicon photodiode 202 .

[0085] In another embodiment, the second amorphous silicon photodiode 202 may also be connected in parallel with the first amorphous silicon photodiode 102 through the conductive via to increase the signal amplitude and reduce noise.

[0086] In this embodiment, the second lower electrode of the second amorphous silicon photodiode 202 is a second transparent lower electrode 204, and the TFT glass substrate 101, the first amorphous silicon photodiode 102 and the second amorphous silicon photodiode 202 form a module unit, and the amorphous silicon photodiode module includes at least two stacked module units, wherein the second transparent lower electrode 204 of the second amorphous silicon photodiode 202 of the upper module unit is connected to the first transparent upper electrode 103 of the first amorphous silicon photodiode 102 of the lower module unit, such as Fig.13 shown.

[0087] In addition, the amorphous silicon photodiode module may further include a first scintillator layer 106 and a second scintillator layer 106, wherein the first scintillator layer 106 is located on the first transparent upper electrode 103 of the first amorphous silicon photodiode 102 at the uppermost layer, and the second scintillator layer 106 is located on the surface of the second transparent lower electrode 204 at the lowermost layer. Fig.14 shown.

[0088] It should be noted that in other embodiments, the through hole may not be prepared in the TFT glass substrate 101, but the signal may be led out to connect the signals of the first amorphous silicon photodiode 102 and the second amorphous silicon photodiode 202 together before entering the front-end readout chip.

[0089] As described above, the amorphous silicon photodiode module of the present invention has the following beneficial effects:

[0090] When preparing an amorphous silicon photodiode based on TFT glass, the present invention changes the electrode adjacent to the TFT glass into a transparent electrode, so that the front amorphous silicon photodiode cannot completely absorb the visible light generated by the scintillator, and the remaining light can penetrate the transparent electrode and reach the back of the glass, and be absorbed by the amorphous silicon photodiode on the back, so that the generated signal is enhanced. At the same time, the front and back amorphous silicon photodiodes can be connected in series through metal vias, so that the large capacitance brought by the thin amorphous silicon photodiode is reduced, or two amorphous silicon photodiodes are connected in parallel, thereby improving light absorption, amplifying the signal amplitude, reducing noise, and improving system performance.

[0091] The present invention can also directly prepare a new scintillator array on the glass back side of the amorphous silicon photodiode with a transparent electrode to absorb more radiation. The generated visible light can also enter the amorphous silicon photodiode on the front side through the transparent electrode to increase the signal amplitude.

[0092] The present invention can be applied to a dual-energy or single-energy detector module in a radiation imaging system, and can also be applied to a TFT type flat panel detector, thereby reducing costs while ensuring or improving system performance and expanding the application field.

[0093] Therefore, the present invention effectively overcomes various shortcomings in the prior art and has high industrial utilization value.

[0094] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. An amorphous silicon photodiode module, characterized in that: The amorphous silicon photodiode module comprises: A TFT glass substrate comprising a first surface and a second surface opposite to the first surface; a first amorphous silicon photodiode, having a first transparent upper electrode and a first transparent lower electrode, wherein the first amorphous silicon photodiode is fixed to the first surface of the TFT glass substrate through the first transparent lower electrode; a module unit is formed by the TFT glass substrate and the first amorphous silicon photodiode, wherein the amorphous silicon photodiode module comprises at least three stacked module units, and two adjacent module units are electrically connected through a conductive through hole; a first scintillator layer, the first scintillator layer being located on the first transparent upper electrode of the first amorphous silicon photodiode; a second amorphous silicon photodiode, having a second transparent upper electrode and a second lower electrode, wherein the second amorphous silicon photodiode is fixed on the second surface of the TFT glass substrate through the second transparent upper electrode and is electrically connected to the first amorphous silicon photodiode; after the light is absorbed by the first amorphous silicon photodiode, the remaining light passes through the first transparent lower electrode of the first amorphous silicon photodiode and the TFT glass substrate and is absorbed by the second amorphous silicon photodiode, so as to increase the signal amplitude of the amorphous silicon photodiode module; the second amorphous silicon photodiode is connected in series with the first amorphous silicon photodiode through a conductive through hole, so as to reduce the large capacitance of the first amorphous silicon photodiode and the second amorphous silicon photodiode, or the second amorphous silicon photodiode is connected in parallel with the first amorphous silicon photodiode through a conductive through hole, so as to increase the signal amplitude and reduce noise; The second lower electrode is a second transparent lower electrode, and the amorphous silicon photodiode module also includes a second scintillator layer, which is located on the second surface of the TFT glass substrate; the first scintillator layer and the second scintillator layer have the same thickness, and the first scintillator and the second scintillator include GOS ceramic scintillators, and the thickness limit of the GOS ceramic scintillator is below 2 mm.

2. The amorphous silicon photodiode module according to claim 1, characterized in that: The first transparent lower electrode includes one of a fully transparent electrode, a combination of a fully transparent electrode and a grid-shaped metal electrode, and a combination of a fully transparent electrode and a dot-shaped metal electrode.

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