JP2003218339A - Radiation detector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To achieve reliable high speed reading of dynamic image by enhancing an open area ratio, in addition to a large area and total digitization not only of general photographing but also of fluoroscopy by improving a sensor reset system in a conventional FPD. <P>SOLUTION: As a switching means of an electric signal obtained at an MIS type photoelectric converting section 11, a transfer TFT 12 performing signal transfer operation and a reset TFT 19 performing signal reset operation by applying a constant potential to the MIS type photoelectric converting section 11 are provided. The reset operation of each pixel in one line on a prestage read out already is performed while signal transfer operation is carried out as read operation for each pixel in one line. <P>COPYRIGHT: (C)2003,JPO

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radiation detecting apparatus for detecting radiation such as X-rays and γ-rays, and more particularly, to a medical image diagnostic apparatus, a non-destructive inspection apparatus, and a radiation apparatus. It is suitable to be applied to an analyzer using the same. 2. Description of the Related Art Conventionally, imaging methods used in medical image diagnosis are largely classified into general imaging for obtaining a still image and fluoroscopy for obtaining a moving image. Each shooting method is as required,
It is selected including the photographing device. [0003] In general photography, that is, a method of obtaining a still image, a method of using a screen film system (hereinafter abbreviated as S / F) combining a fluorescent plate and a film, exposing and developing the film, and then fixing the film, After recording an image as a latent image on a stimulable phosphor, a laser scans the stimulable phosphor, and the output light output information is read by a sensor (Computed Radiography, hereinafter abbreviated as CR). Is common. [0004] However, both methods have a drawback that a workflow for obtaining a radiation image is complicated, and digitization is indirectly possible.
Lack of immediacy, CT and MRI used in other medical imaging
Considering the digitized environment, it is hard to say that the situation is consistent and sufficient. [0005] Further, for fluoroscopy, that is, for a moving image, an image intensifier (hereinafter abbreviated as II) using an electron tube is mainly used. However, since the electron tube is used, the apparatus becomes large-scale. The field of view, that is, the detection area is still small, and there is a strong demand for a larger area in the field of medical image diagnosis. Further, due to a problem in the device configuration, the obtained moving image has much crosstalk, and improvement to a clear image is expected. On the other hand, with the advance of liquid crystal TFT technology and the improvement of information infrastructure, photoelectric conversion elements and switch TFTs using non-single-crystal silicon, for example, amorphous silicon (hereinafter abbreviated as a-Si), have been developed. Flat panel detector (hereinafter abbreviated as FPD) that combines a sensor array composed of the above and a phosphor that converts radiation into visible light, etc. has been proposed, and the possibility of realizing a large area and true digitalization has emerged. Is coming. The FPD is capable of instantly reading a radiation image and instantly displaying it on a display. Further, since the image can be directly retrieved as digital information, data storage, processing, or transfer is possible. There is a feature that the handling is convenient. In addition, various characteristics such as sensitivity depend on imaging conditions, but it has been confirmed that the characteristics are equal to or higher than those of the conventional S / F imaging method and CR imaging method. FIG. 16 shows a schematic equivalent circuit diagram of the FPD. In the figure, 101 is a photoelectric conversion element unit, and 102 is a transfer TF.
T section, 103 is a TFT driving wiring for transfer, 104 is a signal line, 1
05 is a bias wiring, 106 is a signal processing circuit, 107 is
A TFT drive circuit 108 is an A / D converter. Radiation such as X-rays enters and is converted into visible light by a phosphor (not shown). The converted light is converted into a charge by the conversion element 101 and stored in the conversion element 101. Thereafter, the transfer TFT 102 is operated from the TFT drive wiring by the TFT drive circuit 107, the accumulated charge is transferred to the signal line 104, processed by the signal processing circuit 106, and further A / D converted and output at 108. You. [0010] Basically, the above-described element configuration is generally used. In particular, the photoelectric conversion element is a PIN photodiode (hereinafter abbreviated as PIN PD) or employed by the present inventors. Various devices such as a MIS type photoelectric conversion device have been proposed. FIG. 17 is a schematic plan view of one pixel when the photoelectric conversion element is of the MIS type. In the figure, 201 is the MIS
Type photoelectric conversion element, 202 is a transfer TFT, 203 is a transfer TFT drive wiring, 204 is a signal line, 205 is a sensor bias wiring, 211 is a transfer TFT gate electrode, 212 is a transfer TFT source drain electrode (hereinafter abbreviated as SD electrode). And 213, contact holes. FIG. 18 is a schematic sectional view in which the elements in one pixel shown in FIG. 17 are schematically arranged. In the figure, 30
1 is a glass substrate, 302 is a TFT drive wiring for transfer, 303
Is a lower electrode of the MIS type photoelectric conversion element, 304 is a TFT gate electrode for transfer, 305 is a gate insulating film, 306 is an intrinsic a-Si film,
307 is a hole blocking layer, 308 is a bias wiring, 309 is a transfer TFTSD electrode, 310 is a signal line, 320
Denotes a protective film, 321 denotes an organic resin layer, and 322 denotes a phosphor layer. According to the configurations disclosed in FIGS. 17 and 18, since the MIS type photoelectric conversion element and the transfer TFT have the same layer configuration, the manufacturing method is simple, and an advantage that a high yield and a low price can be realized is obtained. It has been evaluated that various characteristics such as sensitivity can be sufficiently satisfied, so the above-mentioned FPD is now used as a device used for general photography instead of the conventional S / F method and CR method Has been reached. [Patent Document 1] US Pat. No. 5,869,837 SUMMARY OF THE INVENTION Problems to be Solved by the Invention
In FPDs, large-area and complete digitalization has been achieved, and it has begun to be mainly used for general photography, but at present it is still not enough in terms of reading speed for fluoroscopic photography. FIG. 19 shows an FPD using an MIS type photoelectric conversion element.
1 is a 1-bit equivalent circuit diagram of FIG. In the figure, C1 is a combined capacitance of the MIS type photoelectric conversion element, C2 is a parasitic capacitance formed in the signal line, Vs is a sensor bias potential, Vr is a sensor reset potential, and SW1 is a Vs / Vr switch for the MIS type photoelectric conversion element. , SW2 is a transfer TFT on / off switch, SW3 is a signal line reset switch, and Vout is an output voltage. A potential Vs is applied to the MIS type photoelectric conversion element by SW1 so that the semiconductor layer is depleted as a bias potential. In this state, when the converted light from the phosphor enters the semiconductor layer, the positive charges blocked by the hole blocking layer are accumulated in the a-Si layer, and a potential difference Vt is generated.
Thereafter, the ON voltage of the transfer TFT is applied from SW2, and the voltage V
Output as out. The output Vout is read by a reading circuit (not shown), and thereafter, the signal line is reset by SW3, and reading is performed sequentially. By sequentially turning on the transfer TFT line by line in accordance with the above-described driving method, all reading of one frame is completed. After that, the reset potential Vr is applied to the MIS type photoelectric conversion element from SW1, reset is performed, the bias potential Vs is applied again, and the image reading accumulation operation starts. For example, in an FPD having a pixel size of 160 μm and a pixel area of 43 cm × 43 cm, the combined capacitance C1 of the MIS type photoelectric conversion element is about 1 pf, and the parasitic capacitance C2 is about 50 pf. Transfer residual of about 2% occurs in C1. Therefore, when shooting
The above-described reset operation is indispensable for maintaining image quality. Specifically, this reset operation requires about 10 msec to several tens msec per frame, and naturally depends on the reset condition. In other words,
In order to realize fluoroscopic imaging requiring high-speed reading of about 30 frames per second (hereinafter abbreviated as 30 FPS) or more, reading processing of all lines and reset processing within 33 msec (30 FPS) per frame And so on. FIG. 20 is a schematic diagram for explaining a conventional FPD driving method. In the figure, T1 is the processing time for reading one line, T2 is the processing time for reading all lines, T
3 is a processing time for resetting and the like, and T is a processing time for one frame. As described above, if one frame processing time T is required to be 33 msec or less, if the reset etc. processing time T3 is 15 msec, T2 is 18 msec, and if 1500 lines are read,
The reading and other processing time T1 assigned to one line is 12 μs
ec. When the radiation exposure time, that is, the sensor accumulation time is included, the processing time T1 for reading and the like is further restricted. As a result, it is necessary to improve the capability of the transfer TFT, which leads to an increase in the size of the TFT at the expense of the aperture ratio, and conversely, problems such as a decrease in sensitivity, a decrease in image quality, and an increase in radiation dose. Frequently occur. That is, there is a trade-off between high-speed moving image driving and image quality, and at present, high-quality high-speed moving images cannot be obtained. In such a situation, U.S. Pat. No. 5,869,837 discloses a radiation imaging system having reset means for periodically resetting capacitively coupled radiation detection means. In this case, the protection film of the readout switch is used as the insulating film of the reset switch, so that there is still room for study on the layer configuration. In addition, the disclosed connection position of the reset switch is not necessarily a configuration in which a complete reset is performed, and there is still room for study in this regard. Accordingly, the present invention improves the sensor reset method in the conventional FPD, and has a large area and complete digitization in not only general radiography but also fluoroscopic radiography, as well as an improved aperture ratio to ensure high-speed moving image reading. To provide a highly reliable ray detection device and a driving method thereof,
In particular, it is an object to provide an optimal arrangement of the sensor reset switch. According to the present invention, there is provided a radiation detecting apparatus comprising: a conversion element for converting radiation into an electric signal; a signal transfer element connected to the conversion element; And a plurality of pixels each including a reset element that performs a reset operation by applying a signal, and the signal transfer element and the reset element are connected to the same electrode of the conversion element. Preferred embodiments to which the present invention is applied will be described below in detail with reference to the drawings. (First Embodiment) In this embodiment, the MIS
Disclosed is an X-ray detector of the FPD type using a photoelectric conversion element as a sensor unit for detecting radiation. FIG. 1 is a schematic equivalent circuit diagram of a 3 × 3 matrix configuration in the X-ray detection apparatus of the present embodiment. Although a 3 × 3 matrix configuration is shown here as an example,
Actually, it is composed of many rows and many columns. In the figure, 11 is an MIS type photoelectric conversion element as a conversion element, and 12 is a transfer element as a first thin film transistor (switch element).
TFT, 13 denotes a transfer TFT drive wiring, 14 denotes a signal line, 15 denotes a bias wiring, 16 denotes a signal processing circuit, 17 denotes a TFT drive circuit, 18 denotes an A / D converter, and 19 denotes a second switch element. TFT for reset, 20 is the wiring for driving the reset TFT, 21
Is a reset wiring. A radiation detector is formed by the conversion element 11 and a wavelength converter that converts the wavelength of radiation, which will be described later. As described above, in the X-ray detector of this embodiment, the MI
As a switching means of the electric signal obtained by the S-type photoelectric conversion element 11, a TFT 12 as a transfer element for performing a signal transfer operation for transferring an electric signal, and an MIS type photoelectric conversion element 1
1 is provided with a TFT 19 as a reset element for performing a signal reset operation by applying a constant potential. X-rays are converted to visible light by a wavelength conversion member such as CsI or GOS, and
Incident on. The incident light is photoelectrically converted and stored in the MIS type photoelectric conversion element. Thereafter, the data is read out by turning on the transfer TFT 12. Thereafter, the reset TFT 19 is turned on to reset the signal charges accumulated in the MIS type photoelectric conversion unit. Note that a capacitor may be separately provided for charge storage. FIG. 2 is a schematic equivalent circuit diagram of a 3 × 1 matrix configuration, and the same reference numerals are given to the same components as those in FIG. The on-voltage of the transfer TFT is applied from Vgt (1) and output via the Sig line. Next, the ON voltage of the reset TFT is applied from Vgr (1), and the sensor is reset. Similarly, the ON voltage of the transfer TFT is applied from Vgt (2) and output via the Sig line. Next, the ON voltage of the reset TFT is applied from Vgr (2), and the sensor is reset. The above operation is shown in FIG. 2 by Vgt (1), Vgr
By sequentially driving in the order of (1), Vgt (2), Vgr (2),..., Vgt (4), Vgr (4),... FIG. 3 is a schematic diagram for explaining a driving method of the X-ray detection device of the present embodiment. In the figure, S1 is the read processing time of one line, S2 is the reset processing time of one line, S4 is the sensor accumulation time, and S is the processing time of one frame. In this embodiment, compared to the conventional method of repeating sequential reading, batch resetting and radiation exposure,
Since reading, resetting, and accumulation can be performed for each line, driving can be performed substantially by the sum of the reading times. That is, while the signal transfer operation is being performed as a read operation for each pixel of one line, the reset operation of each pixel connected to the previous one line that has been read is performed. As a result, high-speed moving image driving of 30 FPS or more can be realized without deteriorating image quality. FIG. 4 is a plan view of one pixel in the X-ray detection apparatus according to the present embodiment. The same reference numerals as those in FIG. 1 denote the same parts. In the drawing, the transfer TFT 12 and the reset TFT 19 are arranged at diagonal positions of pixels on the layout of drive wiring, signal wiring, and the like. FIG.
FIG. 14 is a sectional view taken along line A, and FIG. 14 is a sectional view taken along line BB of FIG. 11 is a photoelectric conversion element, 12 is a TFT for signal transfer, 19
Is a reset TFT. As is clear from this figure,
A configuration in which a lower electrode 303 of a photoelectric conversion element is connected to a signal transfer TFT and a reset gate electrode, that is,
In this configuration, the signal transfer TFT and the reset TFT are connected to the same electrode of the photoelectric conversion element. With such a configuration, a suitable reset operation can be performed. Next, a method of manufacturing the X-ray detector according to this embodiment will be described in the order of steps with reference to FIGS.
First, as shown in FIG. 5A, the driving wiring 13 of the transfer TFT, the gate electrode, the lower electrode 303 of the MIS type photoelectric conversion element, and the driving wiring 20 of the reset TFT are formed. Chromium thin film sputtered to a thickness of 15
A film is formed to a thickness of about 0 nm, and a pattern is formed by photolithography. Next, the SiN gate insulating film, the a-Si film, and the n + film of the TFT and the MIS type photoelectric conversion element are subjected to a plasma CVD apparatus.
About 300 nm, about 600 nm, 100
The film is formed to a thickness of about nm. Subsequently, as shown in FIG.
active ion etching) or CDE (Chemical Dry Etchin)
A contact hole 213 is formed by photolithography using g). Subsequently, as shown in FIG.
As the SD electrodes 24 and 25 of the T and reset TFTs, the signal line 14, the bias wiring 15, and the reset wiring 21, an aluminum thin film (about 1 μm thick) is formed by sputtering, and a pattern is formed by photolithography. Next, transfer TFT
Then, the n + film in the gap portion of the reset TFT is removed by RIE. Subsequently, as shown in FIG. 6B, the elements are separated from each other by photolithography using RIE. Next, after a SiN film is formed as a protective film to a thickness of about 900 nm by a plasma CVD apparatus, a wiring lead portion and the like are exposed by photolithography using RIE. Thereafter, the phosphor is bonded with an adhesive or the like to complete the main structure of the X-ray detection apparatus of the present invention. (Second Embodiment) In this embodiment, the first
The FPD type X-ray detector using the MIS type photoelectric conversion element is disclosed in the same manner as in the first embodiment.
Further sensitivity improvement of the line detection device, in other words, improvement of the aperture ratio,
And to simplify the TFT drive circuit. FIG. 7 is a schematic equivalent circuit diagram of a 3 × 3 matrix configuration in the X-ray detector of the present embodiment. Although a 3 × 3 matrix configuration is shown here as an example,
Actually, it is composed of many rows and many columns. For the sake of convenience, the same components as those in the first embodiment are denoted by the same reference numerals. In the figure, 11 is an MIS type photoelectric conversion element, 12
Is a transfer TFT section, 13 is a transfer and reset TFT drive wiring, 14 is a signal line, 15 is a bias wiring, 16 is a signal processing circuit, 17 is a TFT drive circuit, 18 is an A / D converter, and 19 is a reset TFT. , 21 are reset wirings. X-rays are converted into visible light by a wavelength conversion member such as CsI or GOS, and
Incident on. The incident light is photoelectrically converted and stored. Thereafter, the pixel is read out by turning on the transfer TFT 12 of the pixel. Thereafter, the reset TFT 19 of the pixel is turned on at the timing when the transfer TFT in the subsequent stage operates, and the sensor is reset. FIG. 8 is a schematic equivalent circuit diagram of a 3 × 1 matrix configuration, and reference numerals are the same as those in FIG. An on-voltage of the transfer TFT TT1 is applied from Vg (1) and output via the Sig line. Next, the ON voltage of the reset TFT TR1 is applied from Vg (2), and the sensor is reset. At this time, an on-voltage is applied to the transfer TFT TT2 at the same time, and output similarly via the Sig line. Next, reset TFT TR from Vg (3).
2 ON voltage is applied and the sensor is reset.
By repeating the above operation, moving image reading becomes possible. FIG. 9 is a schematic diagram for explaining a method of driving the X-ray detection device of the present embodiment. In the figure, S1 is one line readout processing time, S2 is one line reset processing time, S4 is sensor accumulation time, and S is one frame processing time. In this embodiment, compared to the conventional method of repeating sequential reading, batch resetting and radiation exposure,
To read, reset and accumulate for each line,
Practically, it can be driven by the sum of the read times. That is, the reset operation of each pixel of the already read one line is performed simultaneously with the signal transfer operation as the read operation for each pixel of one line. As a result, 30FP
High-speed video driving of S or higher can be realized without deteriorating image quality. FIG. 10 is a plan view of one pixel in the X-ray detection apparatus according to the present embodiment, and the reference numerals are the same as those in FIG.
In the drawing, the transfer TFT 12 and the reset TFT 19 are arranged at diagonal positions of pixels on the layout of drive wiring, signal wiring, and the like. Also, since the on-time of the transfer TFT and the reset TFT are the same from the structural feature, the respective TFT capabilities do not necessarily have to be the same, and are determined in consideration of the driving method or image quality. . In the present embodiment, the number of TFT drive wirings is the same as in the prior art, high-speed moving images can be made without largely changing peripheral circuits, and the manufacturing method is as simple as in the first embodiment. . In each of the above-described embodiments, the case where the MIS type photoelectric conversion element is used as the photoelectric conversion means has been exemplified. However, a similar effect can be obtained by using, for example, a PIN type PD. (Third Embodiment) In this embodiment, a so-called direct conversion method is realized, in which radiation is directly converted into electric charges, accumulated, and read out using a transfer TFT. FIG. 11 is a schematic equivalent circuit diagram of a 3 × 3 matrix configuration in the X-ray detection apparatus of the present embodiment.
Here, a 3 × 3 matrix configuration is shown as an example, but in actuality, it is configured with more rows and columns. In the figure, reference numeral 32 denotes an individual electrode for collecting charges generated in the radiation direct conversion unit, 30 denotes a storage capacitor unit,
2 is a transfer TFT unit, 23 is a transfer TFT and reset TFT drive wiring, 24 is a signal line, 26 is a signal processing circuit, and 27 is a TF
T drive circuit, 28 is an A / D converter, 29 is a reset TFT, 3
1 is a reset wiring. FIG. 12 is a schematic cross-sectional view showing the periphery of a pixel in the X-ray detector according to the present embodiment. In the figure, 41 is a glass substrate, 42 is a radiation direct conversion part made of amorphous selenium or GaAs, 50 is a common electrode, and 32 is an individual electrode. Reference numeral 43 denotes a bump connection portion made of a conductive resin;
Are gate electrodes of the transfer TFT and the reset TFT;
46 and 47 are the gate insulating film and the active layer of both TFTs, respectively.
An ohmic contact layer 52 is a lower electrode of the storage portion. The X-rays are converted into electric charges by the radiation direct conversion unit 42, collected by the individual electrodes 32, and
3 and is stored in the storage capacity unit 30. Thereafter, by turning on the transfer TFT 22, the data is read from the signal line 24. Thereafter, at the same time when the transfer TFT in the subsequent stage is turned on, the reset TFT 29 is turned on to reset the sensor and the storage capacitor unit. In this embodiment, the same excellent effects as those in the first and second embodiments can be obtained, and a high-quality moving image can be easily obtained. (Fourth Embodiment) FIG. 15 is a sectional view of a radiation detecting apparatus according to this embodiment. In the present embodiment, the MIS type photoelectric conversion element is stacked on the transfer TFT and the reset TFT via a flattening film. In the figure, 41 is an insulating substrate such as glass, 61 is a gate electrode of a transfer TFT,
62 is a reset TFT gate electrode, 45 is a gate insulating film,
46 is a semiconductor layer, 47 is an ohmic contact layer, 63
Is a flattening film, 64 is a first electrode layer of the photoelectric conversion element, 65 is
Is an insulating layer, 66 is a semiconductor layer, 67 is an ohmic contact layer, and 68 is a second electrode layer. The schematic equivalent circuit diagram of the 3 × 3 matrix configuration may be the same as that shown in FIG. 1 and the like, and the schematic circuit diagram of the 3 × 1 matrix configuration is the same as that shown in FIG. 2 and the like. According to such a configuration, since the photoelectric conversion unit is formed on the driving unit such as a TFT, the aperture ratio is improved and the driving circuit unit including the TFT is simplified. It is possible to do. In particular, when an MIS-type photoelectric conversion element is used as the photoelectric conversion element, a contact hole is formed after the planarization film 63 is formed, and then the first electrode layer and the TFT electrode are contacted. Because the flattening film makes it possible to reduce the thickness of the insulating film of the MIS type photoelectric conversion element, and the sensitivity is improved,
More preferred. Hereinafter, examples of embodiments of the present invention will be listed. [Embodiment 1] A conversion element for converting radiation into an electric signal, a signal transfer element connected to the conversion element, and a reset element for performing a reset operation by applying a constant potential to the conversion element Has a plurality of pixels including
The radiation detection device according to claim 1, wherein the signal transfer element and the reset element are connected to the same electrode of the conversion element. [Second Embodiment] The radiation detecting apparatus according to the first embodiment, wherein the signal transfer element and the reset element are formed of thin film transistors. [Third Embodiment] The radiation detecting apparatus according to the first embodiment, wherein the signal transfer element reset elements are connected to the same drive wiring. [Embodiment 4] The pixels are arranged in a matrix, and the transfer operation by the signal transfer element in a predetermined row is completed before the row.
The radiation detecting apparatus according to claim 1, wherein the radiation detecting apparatus is executed during a reset operation by the resetting element in a row. [Embodiment 5] The transfer elements of the pixels in the predetermined row and the reset elements of the pixels in the previous row are connected to the same drive wiring, and the transfer elements of the pixels in the predetermined row are connected to the same drive wiring. The radiation detecting apparatus according to embodiment 4, wherein a transfer operation by one thin-film transistor and a reset operation by the resetting element of one row in which the transfer operation is completed before the row are performed simultaneously. [Embodiment 6] The conversion element comprises an electrode layer,
The radiation detecting apparatus according to any one of embodiments 1 to 5, wherein the radiation detecting apparatus has a configuration including an insulating layer, a semiconductor layer, and a carrier blocking layer, and has the same layer configuration as the transfer element. [Embodiment 7] The radiation detecting apparatus according to any one of Embodiments 1 to 6, wherein the conversion element is formed using non-single-crystal silicon. [Embodiment 8] The radiation detecting apparatus according to any one of Embodiments 1 to 7, wherein the conversion element has a wavelength conversion member of CsI or GOS for converting radiation into visible light. . [Ninth Embodiment] The radiation detecting apparatus according to any one of the first to fifth embodiments, wherein the conversion element is constituted by a member that directly converts radiation into electric charges. [Embodiment 10] Pixels are arranged in a matrix by detecting means for detecting radiation, transferring means for transferring a detected signal, and resetting means for resetting a signal by applying a potential to a detecting unit. The signal transfer operation of the pixels in a predetermined row, the signal transfer operation being completed before the row.
A method for driving a radiation detection apparatus, which is performed during the signal reset operation of a row. [Embodiment 11] An embodiment characterized in that the signal transfer operation in one predetermined row and the signal reset operation in one row in which the signal readout operation has been completed before the row are simultaneously processed. 11. The driving method of the radiation detection device according to 10. According to the present invention, the sensor reset method in the conventional FPD is improved, so that not only general imaging but also fluoroscopic imaging has a large area and complete digitization.
By improving the aperture ratio, reliable high-speed video reading is realized,
Highly reliable ray detection becomes possible.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows 3 × 3 in the X-ray detection apparatus according to the first embodiment.
FIG. 3 is a schematic equivalent circuit diagram of a matrix configuration. FIG. 2 is a schematic equivalent circuit diagram of a 3 × 1 matrix configuration. FIG. 3 is a schematic diagram for explaining a driving method of the X-ray detection device according to the first embodiment. FIG. 4 is a plan view of one pixel in the X-ray detection device according to the first embodiment. FIG. 5 is a plan view illustrating a method of manufacturing the X-ray detection device according to the first embodiment in the order of steps. FIG. 6 is a plan view showing a method of manufacturing the X-ray detection device in the first embodiment in the order of steps, following FIG. FIG. 7 shows 3 × 3 in the X-ray detection apparatus according to the second embodiment.
FIG. 3 is a schematic equivalent circuit diagram of a matrix configuration. FIG. 8 is a schematic equivalent circuit diagram of a 3 × 1 matrix configuration. FIG. 9 is a schematic diagram for explaining a driving method of the X-ray detection device according to the second embodiment. FIG. 10 is a plan view of one pixel in an X-ray detection device according to a second embodiment. FIG. 11 shows a 3 × image in the X-ray detection apparatus according to the third embodiment.
FIG. 3 is a schematic equivalent circuit diagram of a three-matrix configuration. FIG. 12 is a schematic cross-sectional view illustrating a periphery of a pixel in an X-ray detection device according to a third embodiment. FIG. 13 is a schematic cross-sectional view along AA in FIG. 4; FIG. 14 is a schematic sectional view taken along line BB of FIG. 4; FIG. 15 is a schematic cross-sectional view illustrating a radiation detection apparatus according to a fourth embodiment. FIG. 16 is a schematic equivalent circuit diagram of a conventional FPD X-ray detector. FIG. 17 is a schematic plan view of one pixel when a photoelectric conversion element is an MIS type in a conventional X-ray detection device. FIG. 18 is a schematic sectional view in which elements in one pixel shown in FIG. 17 are schematically arranged. FIG. 19 is a 1-bit equivalent circuit diagram of a conventional X-ray detection device using a MIS type photoelectric conversion element. FIG. 20 is a schematic diagram for explaining a method of driving a conventional FPD type X-ray detection device. [Description of Signs] 101 Photoelectric conversion element unit 12, 22, 102, 202, 302 Transfer TFT unit 13, 103, 203 Transfer TFT drive wiring 14, 24, 104, 310 Signal line 15, 105, 205, 308 Bias Wirings 16, 26, 106 Signal processing circuits 17, 27, 107 TFT drive circuits 18, 28, 108 A / D converters 19, 29 Reset TFT 20 Reset TFT drive wires 21, 31 Reset wire 23 Transfer TFT and reset TFT drive wiring 25 Reset TFT SD electrode 30 Storage capacitor 32 Individual electrode 11, 201 MIS type PD 211, 304 Transfer TFT gate electrode 24, 212, 309 Transfer TFT source / drain electrode 213 Contact hole 41, 301 Glass substrate 303 MIS type PD lower electrode 305 Gate insulating film 306 Intrinsic a-Si film 307 Hole blocking layer 320 Protective film 32 Organic resin layer 322 Phosphor layer 42 Radiation direct change part 50 Common electrode 43 Conductive resin 51 Gate electrodes 45, 46, 47 of transfer TFT and reset TFT Gate insulating film, active layer, ohmic contact layer 52 Lower electrode of storage part C1 Combined capacitance C of MIS type PD C2 Parasitic capacitance Vs formed in signal line Sensor bias potential Vr Sensor reset potential SW1 Vs / Vr switch SW2 of MIS type PD ON / OFF switch SW3 of transfer TFT SW3 Signal line reset switch Vout Output Voltage Vt Potential difference S1, T1 One line reading processing time T2 All line reading processing time T3 Reset processing time S, T One frame processing time S2 One line reset processing time S3 One line processing time S4 Sensor accumulation time

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H01L 27/14 H04N 5/335 U 31/09 H01L 27/14 C H04N 5/32 31/00 A 5 / 335 27/14 K F term (for reference) 2G088 EE01 EE30 FF02 FF04 GG19 GG20 GG21 JJ04 JJ05 JJ09 JJ31 JJ33 KK32 KK40 LL11 LL12 LL17 LL18 4M118 AA01 AA10 AB01 BA05 CA05 CA07 CB02 G03 CB02 G03 DX06 5F088 AA04 AB05 BB03 BB07 EA04 EA08 HA15 KA03 KA08 LA08

Claims (1)

1. A conversion element for converting radiation into an electric signal, a signal transfer element connected to the conversion element, and a reset for applying a constant potential to the conversion element to perform a reset operation. A radiation detection device, comprising: a plurality of pixels each including a first element and a second element; wherein the signal transfer element and the reset element are connected to the same electrode of the conversion element.