JP2013156119A - Radiation imaging apparatus, manufacturing method thereof, and radiation imaging display system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a radiation imaging apparatus with reduced manufacturing costs.SOLUTION: A radiation imaging apparatus 1 comprises a sensor substrate 10 having: a plurality of photodiodes 111A as photoelectric conversion elements formed on a substrate 11; a thin-film transistor 111B as a driving element for the photodiodes 111A; and a wavelength conversion layer 20 which converts wavelengths of incident radiation into those in a sensitive region of the photoelectric conversion elements. The wavelength conversion layer 20 is directly formed within the sensor substrate 10, so that there is no need to additionally attach a substrate having a wavelength conversion layer, reducing manufacturing processes and thereby lowering manufacturing costs.

Description

  The present disclosure relates to a radiation imaging apparatus having a sensor substrate including a photoelectric conversion element, a manufacturing method thereof, and a radiation imaging display system including such a radiation imaging apparatus.

  2. Description of the Related Art Conventionally, various devices have been proposed as imaging devices in which photoelectric conversion elements (photodiodes) are built in each pixel (imaging pixel). As an example of an imaging apparatus having such a photoelectric conversion element, a so-called optical touch panel, a radiation imaging apparatus (see, for example, Patent Document 1), and the like can be given.

JP 2007-332172 A

  By the way, in the radiation imaging apparatus described above, since it is generally required to suppress the manufacturing cost as much as possible, a proposal of a method for reducing the manufacturing cost is desired.

  The present disclosure has been made in view of such problems, and an object of the present disclosure is to provide a radiation imaging apparatus capable of reducing the manufacturing cost, a manufacturing method thereof, and a radiation imaging display system including such a radiation imaging apparatus. It is to provide.

  A radiation imaging apparatus of the present disclosure includes a sensor substrate having a plurality of photoelectric conversion elements formed on a substrate and a wavelength conversion layer that converts the wavelength of incident radiation into the sensitivity range of the photoelectric conversion elements, and the wavelength conversion layer includes It is formed directly in the sensor substrate.

  A radiation imaging display system according to the present disclosure includes the radiation imaging apparatus according to the present disclosure and a display device that performs image display based on an imaging signal obtained by the radiation imaging apparatus.

  The manufacturing method of the radiation imaging apparatus of this indication includes the process of forming a sensor substrate. The step of forming the sensor substrate includes a step of forming a plurality of photoelectric conversion elements on the substrate, and a wavelength conversion layer that converts the wavelength of incident radiation into the sensitivity range of the photoelectric conversion element on the upper layer side of the photoelectric conversion element. Forming directly.

  In the radiation imaging apparatus, the manufacturing method thereof, and the radiation imaging display system of the present disclosure, the wavelength conversion layer that converts the wavelength of incident radiation into the sensitivity range of the photoelectric conversion element is directly formed in the sensor substrate. Thereby, compared with the case where the wavelength conversion member is separately bonded on the sensor substrate, the manufacturing process is reduced by the amount that the bonding process is unnecessary.

  According to the radiation imaging apparatus, the manufacturing method thereof, and the radiation imaging display system of the present disclosure, the wavelength conversion layer that converts the wavelength of incident radiation into the sensitivity range of the photoelectric conversion element is directly formed in the sensor substrate. The manufacturing process can be reduced, and the manufacturing cost can be reduced.

It is sectional drawing showing the structural example of the radiation imaging device which concerns on one embodiment of this indication. FIG. 2 is a block diagram illustrating a configuration example of a sensor substrate illustrated in FIG. 1. FIG. 2 is a plan view illustrating a configuration example of a sensor substrate illustrated in FIG. 1. It is a figure showing the cross-sectional structural example along the III-III line | wire shown in FIG. It is sectional drawing represented to 1 process in the manufacturing method of the radiation imaging device shown in FIG. FIG. 6 is a cross-sectional view illustrating a process following FIG. 5. FIG. 7 is a cross-sectional view illustrating a process following FIG. 6. FIG. 8 is a cross-sectional diagram illustrating a process following the process in FIG. 7. FIG. 9 is a cross-sectional diagram illustrating a process following the process in FIG. 8. It is sectional drawing showing the structure and effect | action of the radiation imaging device which concerns on a comparative example. It is a schematic diagram showing schematic structure of the radiation imaging display system which concerns on an application example.

Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. The description will be given in the following order.

1. Embodiment (example of radiation imaging apparatus in which wavelength conversion layer is directly formed in sensor substrate)
2. Application example (application example to radiation imaging display system)
3. Modified example

<Embodiment>
[Cross-sectional configuration of radiation imaging apparatus 1]
FIG. 1 illustrates a cross-sectional configuration example of a radiation imaging apparatus (radiation imaging apparatus 1) according to an embodiment of the present disclosure. The radiation imaging apparatus 1 receives radiation after wavelength conversion of radiation represented by α rays, β rays, γ rays, and X rays, and reads image information based on the radiation (images a subject). The radiation imaging apparatus 1 is suitably used as an X-ray imaging apparatus for medical use and other nondestructive inspections such as baggage inspection.

  The radiation imaging apparatus 1 includes a sensor substrate 10 in which a wavelength conversion layer 20 (wavelength conversion unit) described later is built (formed directly). That is, the wavelength conversion layer 20 is integrally manufactured as the same module as the sensor substrate 10.

  The sensor substrate 10 has a plurality of pixels (unit pixels P described later). In the sensor substrate 10, a pixel circuit including a plurality of photodiodes 111A (photoelectric conversion elements) and thin film transistors (TFTs) 111B as driving elements of the photodiodes 111A is formed on the surface of the substrate 11. It is a thing. In the present embodiment, the photodiode 111A and the thin film transistor 111B are juxtaposed on the substrate 11 made of glass or the like, and part of them (here, a gate insulating film 121 and a first interlayer insulating film described later). 112A and the second interlayer insulating film 112B) are common layers.

The gate insulating film 121 is provided on the substrate 11, for example, a single layer film made of one of a silicon oxide (SiO ₂ ) film, a silicon oxynitride (SiON) film, and a silicon nitride film (SiN), or these It is comprised by the laminated film which consists of 2 or more types of these.

  The first interlayer insulating film 112A is provided on the gate insulating film 121 and is made of an insulating film such as a silicon oxide film or a silicon nitride film. The first interlayer insulating film 112A also functions as a protective film (passivation film) that covers a thin film transistor 111B described later.

(Photodiode 111A)
The photodiode 111A is a photoelectric conversion element that generates a charge (photocharge) having a charge amount corresponding to the amount of incident light (amount of received light) and accumulates the charge therein, for example, a PIN (Positive Intrinsic Negative Diode) type photodiode. Consists of. In the photodiode 111A, the sensitivity range is, for example, the visible range (the light reception wavelength band is the visible range). For example, the photodiode 111A is disposed in a selective region on the substrate 11 via a gate insulating film 121 and a first interlayer insulating film 112A.

  Specifically, in the photodiode 111A, the lower electrode 124, the n-type semiconductor layer 125N, the i-type semiconductor layer 125I, the p-type semiconductor layer 125P, and the upper electrode 126 are stacked in this order on the first interlayer insulating film 112A. Become. In this example, the n-type semiconductor layer 125N is provided on the substrate side (lower side) and the p-type semiconductor layer 125P is provided on the upper side, but the opposite structure, that is, the lower side (substrate side) is provided. A structure in which a p-type semiconductor layer and an n-type semiconductor layer on the upper side may be employed.

  The lower electrode 124 is an electrode for reading signal charges from the photoelectric conversion layer (n-type semiconductor layer 125N, i-type semiconductor layer 125I, p-type semiconductor layer 125P), and is connected to a drain electrode 123D described later in the thin film transistor 111B. Has been. The lower electrode 124 has a three-layer structure (Mo / Al / Mo) in which molybdenum (Mo), aluminum (Al), and molybdenum are stacked, for example.

  The n-type semiconductor layer 125N is made of amorphous silicon (amorphous silicon: a-Si), for example, and forms an n + region. The thickness of the n-type semiconductor layer 125N is, for example, about 10 nm to 50 nm.

  The i-type semiconductor layer 125I is a semiconductor layer having lower conductivity than the n-type semiconductor layer 125N and the p-type semiconductor layer 125P, for example, an undoped intrinsic semiconductor layer, and is made of, for example, amorphous silicon (a-Si). Yes. The thickness of the i-type semiconductor layer 125I is, for example, about 400 nm to 1000 nm. The greater the thickness, the higher the photosensitivity.

  The p-type semiconductor layer 125P is made of amorphous silicon (a-Si), for example, and forms a p + region. The thickness of the p-type semiconductor layer 125P is, for example, about 40 nm to 50 nm.

  The upper electrode 126 is an electrode for supplying, for example, a reference potential (bias potential) at the time of photoelectric conversion to the above-described photoelectric conversion layer, and is connected to a wiring layer 127 which is a power supply wiring for supplying a reference potential. The upper electrode 126 is made of a transparent conductive film such as ITO (Indium Tin Oxide).

(Thin film transistor 111B)
The thin film transistor 111B is made of, for example, a field effect transistor (FET). In the thin film transistor 11B, a gate electrode 120 made of, for example, titanium (Ti), Al, Mo, tungsten (W), chromium (Cr) or the like is formed on the substrate 11, and the gate insulating film described above is formed on the gate electrode 120. 121 is formed.

  A semiconductor layer 122 is formed over the gate insulating film 121, and the semiconductor layer 122 has a channel region. The semiconductor layer 122 is made of, for example, polycrystalline silicon, microcrystalline silicon, or amorphous silicon. Or you may be comprised by oxide semiconductors, such as indium gallium zinc oxide (InGaZnO) or zinc oxide (ZnO).

  On the semiconductor layer 122, a source electrode 123S and a drain electrode 123D connected to a signal line for reading and various wirings are formed. Specifically, here, the drain electrode 123D is connected to the lower electrode 124 in the photodiode 111A, and the source electrode 123S is connected to a vertical signal line 18 (source line) described later. Each of the source electrode 123S and the drain electrode 123D is made of, for example, Ti, Al, Mo, W, Cr, or the like.

  In the sensor substrate 10, the second interlayer insulating film 112B, the planarizing film 113, the protective film 114, and the wavelength conversion layer 20 are provided in this order on the photodiode 111A and the thin film transistor 111B.

  The second interlayer insulating film 112B is provided so as to cover the thin film transistor 111B and end portions of the side surface and the upper surface (on the upper electrode 127) of the photodiode 111A. For example, an insulating film such as a silicon oxide film or a silicon nitride film is provided. It consists of a membrane.

  The planarizing film 113 is disposed on the upper layer side of the photodiode 111A and the thin film transistor 111B and is made of a transparent resin material such as polyimide. The thickness of the flattened film 113 is desirably about 2.1 μm or less, for example, in a portion (flat portion) excluding the formation region of the photodiode 111A. This is to achieve both the action of suppressing the incidence of stray light (incident light from adjacent pixels), which will be described later, and the flattening action (breaking prevention action). In the planarizing film 113, an opening H1 is formed corresponding to the vicinity of the formation region of the photodiode 111A. The side surface of the opening H1 is tapered, and this side surface is disposed on the upper electrode 126 of the photodiode 111A.

  The protective film 114 is provided on the entire surface of the upper electrode 126, the wiring layer 127, and the planarizing film 113, and is made of an insulating film such as a silicon oxide film or a silicon nitride film.

(Wavelength conversion layer 20)
The wavelength conversion layer 20 converts the wavelength of radiation (for example, X-rays) incident from outside into the sensitivity range (visible range) of the photodiode 111A. As described above, the wavelength conversion layer 20 is directly formed in the sensor substrate 10 (which is integrally formed as the same module as the sensor substrate 10). Particularly in the present embodiment, the wavelength conversion layer 20 is selectively formed corresponding to the formation region of the photodiode 111A. Specifically, the wavelength conversion layer 20 is embedded in the opening H1 of the planarization film 113 (embedded or embedded).

Such a wavelength conversion layer 20 is configured by using, for example, a scintillator (phosphor) that converts radiation (X-rays) into visible light, and it is particularly preferable that the wavelength conversion layer 20 be configured by using a liquid scintillator. Examples of such phosphors include those obtained by adding thallium (Tl) to cesium iodide (CsI) (CsI; Tl), and those obtained by adding terbium (Tb) to sulfur cadmium oxide (Gd ₂ O ₂ S). BaFX (X is Cl, Br, I, etc.) and the like.

  In addition, although mentioned later for details, the wavelength conversion layer 20 which consists of a liquid scintillator is formed when a liquid scintillator is dripped using the inkjet method etc. in the sensor board | substrate 10 (for example, inside opening part H1), for example. It is like that.

[Detailed Configuration of Sensor Board 10]
FIG. 2 shows a functional block configuration of the sensor substrate 10 as described above. The sensor substrate 10 has a pixel unit 12 as an imaging region (imaging unit) on a substrate 11, and a row scanning unit 13, a horizontal selection unit 14, a column scanning unit 15, and the like are arranged in a peripheral region of the pixel unit 12. A peripheral circuit (drive circuit) including the system control unit 16 is included.

(Pixel part 12)
The pixel unit 12 includes, for example, unit pixels P that are two-dimensionally arranged in a matrix (hereinafter sometimes simply referred to as “pixels”), and the unit pixel P includes the photodiode 111A and the thin film transistor 111B described above. It is out. In the unit pixel P, for example, a pixel drive line 17 (for example, a row selection line and a reset control line: a gate line) is wired for each pixel row, and a vertical signal line 18 (source line) is wired for each pixel column. Yes. The pixel drive line 17 transmits a drive signal for reading a signal from the unit pixel P. One end of the pixel drive line 17 is connected to an output end corresponding to each row of the row scanning unit 13.

  Here, FIG. 3 illustrates a planar configuration example of the unit pixel P in the sensor substrate 10 (pixel unit 12). Thus, in the unit pixel P, the drain electrode 123D of the thin film transistor 111B (driving element) is connected to the lower electrode 124 of the photodiode 111A, and the source electrode 123S is connected to the vertical signal line 18. 3 corresponds to the cross-sectional configuration of the sensor substrate 10 shown in FIG. 1. The cross-sectional configuration example along the line II-II shown in FIG.

  On the other hand, FIG. 4 shows a cross-sectional configuration example of the sensor substrate 10 taken along the line III-III shown in FIG. The cross-sectional configuration shown in FIG. 4 is basically the same as the cross-sectional configuration shown in FIG. 1, but the vertical signal line 18 is formed on the substrate 11 instead of the thin film transistor 111B. Specifically, the vertical signal line 18 is provided in a selective region (corresponding to the formation region of the thin film transistor 111B in FIG. 1) between the gate insulating film 121 and the first interlayer insulating film 112A.

(Peripheral circuit)
The row scanning unit 13 illustrated in FIG. 2 includes a shift register, an address decoder, and the like, and is a pixel driving unit that drives each pixel P of the pixel unit 12 in units of rows, for example. A signal (imaging signal) output from each pixel P in the pixel row selected and scanned by the row scanning unit 13 is supplied to the horizontal selection unit 14 through each vertical signal line 18.

  The horizontal selection unit 14 is configured by an amplifier, a horizontal selection switch, and the like provided for each vertical signal line 18.

  The column scanning unit 15 is configured by a shift register, an address decoder, and the like, and drives each of the horizontal selection switches of the horizontal selection unit 14 in order while scanning. By the selective scanning by the column scanning unit 15, the signal of each pixel transmitted through each of the vertical signal lines 18 is sequentially output to the horizontal signal line 19 and is transmitted to the outside of the substrate 11 through the horizontal signal line 19. It has become.

  The circuit portion including the row scanning unit 13, the horizontal selection unit 14, the column scanning unit 15, and the horizontal signal line 19 may be formed directly on the substrate 11, or may be an external control IC (Integrated Circuit). ) May be provided. In addition, these circuit portions may be formed on another substrate connected by a cable or the like.

  The system control unit 16 receives a clock given from the outside of the substrate 11, data for instructing an operation mode, and the like, and outputs data such as internal information of the radiation imaging apparatus 1. The system control unit 16 further includes a timing generator that generates various timing signals. Based on the various timing signals generated by the timing generator, the row scanning unit 13, the horizontal selection unit 14, the column scanning unit 15, and the like. The peripheral circuit is driven and controlled.

[Manufacturing Method of Imaging Device 1]
The radiation imaging apparatus 1 as described above can be manufactured, for example, as follows. 5 to 9 show an example of a method for manufacturing the radiation imaging apparatus 1 (a method for manufacturing the sensor substrate 10) in cross-sectional view in the order of steps.

  First, as shown in FIG. 5, a thin film transistor 111B is formed on a substrate 11 made of glass, for example, by a known thin film process. Subsequently, a first interlayer insulating film 112A made of the above-described material is formed on the thin film transistor 111B by using, for example, a CVD (Chemical Vapor Deposition) method and a photolithography method. After that, the lower electrode 124 made of the above-described material is formed by using, for example, a sputtering method and a photolithography method so as to be electrically connected to the drain electrode 123D in the thin film transistor 111B.

  Next, as shown in FIG. 6, an n-type semiconductor layer 125N, an i-type semiconductor layer 125I, and a p-type semiconductor layer 125P made of the above-described materials are formed in this order on the entire surface of the first interlayer insulating film 112A, for example, by CVD. The film is formed by After that, the upper electrode 126 made of the above-described material is formed in a region where the photodiode 111A is to be formed on the p-type semiconductor layer 125P by using, for example, a sputtering method and a photolithography method.

  Subsequently, as shown in FIG. 7, the stacked structure of the formed n-type semiconductor layer 125N, i-type semiconductor layer 125I, and p-type semiconductor layer 125P is patterned into a predetermined shape by using, for example, a dry etching method. As a result, the photodiode 111 </ b> A is formed on the substrate 11.

  Next, as shown in FIG. 8, the second interlayer insulating film 112B made of the above-described material is formed on the thin film transistor 111B and on the side surface and top surface (upper electrode 127) of the photodiode 111A using, for example, the CVD method and the photolithography method. It is formed so as to cover the upper part. Thereafter, a planarizing film 113 made of the above-described material is formed on the entire surface of the second interlayer insulating film 112B (on the upper side of the photodiode 111A and the thin film transistor 111B) by using, for example, a CVD method. Then, for example, by performing etching (dry etching or the like) using a photolithography method, the opening H1 is formed corresponding to the formation region of the photodiode 111A in the planarization film 113.

  Subsequently, as shown in FIG. 9, a wiring layer 127 made of, for example, Al, Cu or the like is formed in the opening H1 (on the upper electrode 126) in the planarizing film 113 by using, for example, a sputtering method and a photolithography method. Form. Next, the protective film 114 made of the above-described material is formed on the entire surface of the planarizing film 113, the upper electrode 126, and the wiring layer 127 by using, for example, a CVD method.

  After that, the wavelength conversion layer 20 made of the above-described material (scintillator) is directly formed on the upper layer side of the photodiode 111A (here, in the opening H1 on the protective film 114). That is, here, the wavelength conversion layer 20 is selectively formed corresponding to the formation region of the photodiode 111A (embedded in the opening H1). At this time, for example, as shown in FIG. 9, it is desirable to form the wavelength conversion layer 20 made of the liquid scintillator by dropping the liquid scintillator into the opening H1 using an ink jet method or the like. Thus, the sensor substrate 10 (radiation imaging apparatus 1) shown in FIG. 1 is completed.

[Operation and Effect of Imaging Device 1]
(1. Imaging operation)
In this radiation imaging apparatus 1, for example, when radiation irradiated from a radiation source (not shown) (for example, an X-ray source) and transmitted through a subject (detector) is incident, the incident radiation is photoelectrically converted after wavelength conversion, and an image of the subject is obtained. Is obtained as an electrical signal (imaging signal). Specifically, the radiation incident on the radiation imaging apparatus 1 is first converted into a wavelength in the sensitivity region (here, the visible region) of the photodiode 111A in the wavelength conversion layer 20 in the sensor substrate 10 (wavelength conversion layer 20). Emits visible light).

  Next, in the sensor substrate 10, when a predetermined reference potential (bias potential) is applied to one end (for example, the upper electrode 126) of the photodiode 111 </ b> A via the wiring 127, light incident from the upper electrode 126 side is generated. Then, it is converted into a signal charge having a charge amount corresponding to the received light amount (photoelectric conversion is performed). The signal charge generated by this photoelectric conversion is taken out as a photocurrent from the other end (for example, the lower electrode 124) side of the photodiode 111A.

  Specifically, the charge generated by photoelectric conversion in the photodiode 111A is read out as a photocurrent and output as an imaging signal from the thin film transistor 111B. The imaging signal output in this way is output (read out) to the vertical signal line 18 in accordance with the row scanning signal transmitted from the row scanning unit 13 via the pixel drive line 17. The imaging signal output to the vertical signal line 18 is output to the horizontal selection unit 14 for each pixel column through the vertical signal line 18. Then, by the selective scanning by the column scanning unit 15, the imaging signal of each pixel transmitted through each of the vertical signal lines 18 is sequentially output to the horizontal signal line 19, and is transmitted to the outside of the substrate 11 through the horizontal signal line 19. (Output data Dout is output to the outside). As described above, a captured image using radiation is obtained in the radiation imaging apparatus 1.

(2. Action in sensor substrate 10)
Here, with reference to FIG. 1 and FIG. 10, the effect | action in the radiation imaging device 1 (sensor board | substrate 10) of this Embodiment is demonstrated in detail, comparing with a comparative example.

(Comparative example)
FIG. 10 illustrates a cross-sectional configuration of a radiation imaging apparatus (radiation imaging apparatus 100) according to a comparative example. Unlike the radiation imaging apparatus 1 of the present embodiment shown in FIG. 1, the radiation imaging apparatus 100 of this comparative example is provided with a sensor substrate 101 and a wavelength conversion member 102 individually. Specifically, in the radiation imaging apparatus 100, a wavelength conversion member 102 (scintillator plate) using a scintillator is bonded to a sensor substrate 101, and the sensor substrate 101 and the wavelength conversion member 102 are separate modules. It has been produced as. Note that in the sensor substrate 101, a two-layer planarization film of a first planarization film 113 </ b> A corresponding to the planarization film 113 in the sensor substrate 10 and a second planarization film 113 </ b> B provided on the entire surface of the protective film 114. Is provided.

  In this radiation imaging apparatus 100, as described above, the wavelength conversion member 102 is separately bonded onto the sensor substrate 101. For this reason, a manufacturing process will increase by the part of these bonding processes, and manufacturing cost will increase. In addition, in order to perform this bonding, it is necessary to provide a planarization film (second planarization film 113B) also on the protective film 114, which also increases the manufacturing cost.

  Furthermore, as shown in FIG. 10, since the visible light L101 emitted from the wavelength conversion member 102 enters the photodiode 111A via the second planarization film 113B, the thickness of the second planarization film 113B. Therefore, the visible light L101 is attenuated. Such attenuation of the visible light L101 causes a decrease in the S / N ratio in the image pickup signal obtained from the photodiode 111A, leading to deterioration of the image quality of the picked-up image.

  In addition, stray light L102 from an adjacent pixel or the like enters the photodiode 111A via the second planarization film 113B and the first planarization film 113A. As a result, the noise component (noise component due to stray light L102) in the imaging signal obtained from the photodiode 111A increases. That is, image quality degradation of the captured image also occurs at this point.

(This embodiment)
On the other hand, in the radiation imaging apparatus 1 of the present embodiment, as shown in FIG. 1, the wavelength conversion layer 20 is directly formed in the sensor substrate 10 (built in the sensor substrate 10). As a result, as compared with the case where the wavelength conversion member 102 is separately bonded onto the sensor substrate 101 as in the comparative example, the number of manufacturing processes can be reduced to the extent that this bonding process is unnecessary.

  Further, unlike the comparative example, the second planarizing film 113B is not necessary, and thus the manufacturing cost is reduced. Further, since the attenuation of incident light (visible light) from the wavelength conversion layer 20 to the photodiode 111A is suppressed by the thickness of the second planarizing film 113B, the S / N in the imaging signal is compared with the comparative example. The ratio is improved and the image quality of the captured image is improved.

  Further, the wavelength conversion layer 20 is selectively formed corresponding to the formation region of the photodiode 111A (embedded in the opening H1 of the planarization film 113). Thus, unlike the comparative example, stray light from adjacent pixels or the like is prevented from entering the photodiode 111A. As a result, the noise component (noise component due to stray light) in the image pickup signal obtained from the photodiode 111A is reduced, and the image quality of the picked-up image is also improved in this respect.

  As described above, in the present embodiment, the wavelength conversion layer 20 that converts the wavelength of incident radiation into the sensitivity range of the photodiode 111A is directly formed in the sensor substrate 10, thereby reducing the manufacturing process. Thus, the manufacturing cost can be reduced.

  Further, for example, by optimizing the taper position and taper angle of the opening H1 (contact hole) in the planarization film 113, the amount of visible light reaching the photodiode 111A is increased, and the S / N ratio is improved. It is also possible.

<Application example>
Next, an application example of the radiation imaging apparatus according to the above embodiment to a radiation imaging display system will be described.

  FIG. 11 schematically illustrates a schematic configuration example of a radiation imaging display system (radiation imaging display system 5) according to an application example. The radiation imaging display system 5 includes a radiation imaging apparatus 1 having the pixel unit 12 and the like according to the above-described embodiment, an image processing unit 52, and a display apparatus 4, and an imaging display system (radiation) using radiation. Imaging display system).

  The image processing unit 52 generates image data D1 by performing predetermined image processing on output data Dout (imaging signal) output from the radiation imaging apparatus 1. The display device 4 performs image display on the predetermined monitor screen 40 based on the image data D <b> 1 generated by the image processing unit 52.

  In the radiation imaging display system 5 having such a configuration, the radiation imaging apparatus 1 is based on irradiation light (here, radiation) emitted toward a subject 50 from a light source (here, a radiation source 51 such as an X-ray source). The image data Dout of the subject 50 is acquired and output to the image processing unit 52. The image processing unit 52 performs the predetermined image processing described above on the input image data Dout, and outputs the image data (display data) D1 after the image processing to the display device 4. The display device 4 displays image information (captured image) on the monitor screen 40 based on the input image data D1.

  Thus, in the radiation imaging display system 5 of this application example, since the image of the subject 50 can be acquired as an electrical signal in the radiation imaging apparatus 1, image display is performed by transmitting the acquired electrical signal to the display device 4. It can be carried out. That is, it is possible to observe the image of the subject 50 without using a conventional radiographic film, and it is also possible to handle moving image shooting and moving image display.

<Modification>
The technology of the present disclosure has been described above with the embodiments and application examples, but the technology is not limited to these embodiments and the like, and various modifications are possible.

  For example, in the above embodiment and the like, the case where the semiconductor layer in the photodiode 111A and the thin film transistor 111B is mainly composed of an amorphous semiconductor (such as amorphous silicon) has been described as an example. Is not limited. That is, the above-described semiconductor layer may be configured of, for example, a polycrystalline semiconductor (polycrystalline silicon or the like) or a microcrystalline semiconductor (microcrystalline silicon or the like).

  In the above-described embodiment, the wavelength conversion layer 20 is selectively formed corresponding to the formation region of the photodiode 111A (embedded in the opening H1 of the planarization film 113). Although described as an example, this is not a limitation. That is, for example, the wavelength conversion layer 20 may be directly formed on the entire surface of the sensor substrate 10.

In addition, this technique can also take the following structures.
(1)
A sensor substrate having a plurality of photoelectric conversion elements formed on the substrate and a wavelength conversion layer that converts the wavelength of incident radiation into the sensitivity range of the photoelectric conversion elements,
The radiation imaging apparatus, wherein the wavelength conversion layer is directly formed in the sensor substrate.
(2)
The radiation imaging apparatus according to (1), wherein the wavelength conversion layer is selectively formed corresponding to a formation region of the photoelectric conversion element.
(3)
The sensor substrate has a planarizing film that is disposed on an upper layer side of the photoelectric conversion element and has an opening formed corresponding to a formation region of the photoelectric conversion element.
The radiation imaging apparatus according to (2), wherein the wavelength conversion layer is embedded in the opening of the planarization film.
(4)
The radiation imaging apparatus according to any one of (1) to (3), wherein the wavelength conversion layer is configured using a liquid scintillator.
(5)
The radiation imaging apparatus according to (4), wherein the wavelength conversion layer is formed by dropping the liquid scintillator in the sensor substrate.
(6)
The radiation imaging apparatus according to any one of (1) to (5), wherein the photoelectric conversion element includes a PIN type photodiode.
(7)
The radiation imaging apparatus according to any one of (1) to (6), wherein the radiation is X-rays.
(8)
A radiation imaging device, and a display device that displays an image based on an imaging signal obtained by the radiation imaging device,
The radiation imaging apparatus includes:
A sensor substrate having a plurality of photoelectric conversion elements formed on the substrate and a wavelength conversion layer that converts the wavelength of incident radiation into the sensitivity range of the photoelectric conversion elements,
The radiation imaging display system, wherein the wavelength conversion layer is directly formed in the sensor substrate.
(9)
Forming a sensor substrate;
The step of forming the sensor substrate includes:
Forming a plurality of photoelectric conversion elements on a substrate;
A step of directly forming a wavelength conversion layer that converts the wavelength of incident radiation into a sensitivity range of the photoelectric conversion element on the upper layer side of the photoelectric conversion element.
(10)
The method for manufacturing a radiation imaging apparatus according to (9), wherein the wavelength conversion layer is formed by dropping a liquid scintillator on the upper layer side of the photoelectric conversion element.
(11)
The method for manufacturing a radiation imaging apparatus according to (10), wherein the liquid scintillator is dropped using an ink jet method.

  DESCRIPTION OF SYMBOLS 1 ... Radiation imaging device, 10 ... Sensor board | substrate, 11 ... Board | substrate, 111A ... Photodiode (photoelectric conversion element), 111B ... Thin-film transistor, 112A ... 1st interlayer insulation film, 112B ... 2nd interlayer insulation film, 113 ... Planarization film , 114 ... protective film, 12 ... pixel unit, 17 ... pixel drive line, 18 ... vertical signal line, 20 ... wavelength conversion layer, 4 ... display device, 5 ... radiation imaging display system, 50 ... subject, 51 ... radiation source, H1... Opening, P... Unit pixel.

Claims (11)

A sensor substrate having a plurality of photoelectric conversion elements formed on the substrate and a wavelength conversion layer that converts the wavelength of incident radiation into the sensitivity range of the photoelectric conversion elements,
The radiation imaging apparatus, wherein the wavelength conversion layer is directly formed in the sensor substrate. The radiation imaging apparatus according to claim 1, wherein the wavelength conversion layer is selectively formed corresponding to a formation region of the photoelectric conversion element. The sensor substrate has a planarizing film that is disposed on an upper layer side of the photoelectric conversion element and has an opening formed corresponding to a formation region of the photoelectric conversion element.
The radiation imaging apparatus according to claim 2, wherein the wavelength conversion layer is embedded in the opening of the planarization film. The radiation imaging apparatus according to claim 1, wherein the wavelength conversion layer is configured using a liquid scintillator. The radiation imaging apparatus according to claim 4, wherein the wavelength conversion layer is formed by dropping the liquid scintillator in the sensor substrate. The radiation imaging apparatus according to claim 1, wherein the photoelectric conversion element is a PIN type photodiode. The radiation imaging apparatus according to claim 1, wherein the radiation is X-rays. A radiation imaging device, and a display device that displays an image based on an imaging signal obtained by the radiation imaging device,
The radiation imaging apparatus includes:
A sensor substrate having a plurality of photoelectric conversion elements formed on the substrate and a wavelength conversion layer that converts the wavelength of incident radiation into the sensitivity range of the photoelectric conversion elements,
The radiation imaging display system, wherein the wavelength conversion layer is directly formed in the sensor substrate. Forming a sensor substrate;
The step of forming the sensor substrate includes:
Forming a plurality of photoelectric conversion elements on a substrate;
A step of directly forming a wavelength conversion layer that converts the wavelength of incident radiation into a sensitivity range of the photoelectric conversion element on the upper layer side of the photoelectric conversion element. The method for manufacturing a radiation imaging apparatus according to claim 9, wherein the wavelength conversion layer is formed by dropping a liquid scintillator on an upper layer side of the photoelectric conversion element. The method for manufacturing a radiation imaging apparatus according to claim 10, wherein the liquid scintillator is dropped using an ink jet method.

Images