CN-122003622-A - X-ray detector

CN122003622ACN 122003622 ACN122003622 ACN 122003622ACN-122003622-A

Abstract

An X-ray detector includes, as a drive sequence having a repetition standby section, a preparation section, an accumulation section, and a readout section, a first electrode on a substrate to which a pixel voltage is applied, a photoelectric material layer on the first electrode, and a second electrode on the photoelectric material layer, wherein a switching voltage equal to or lower than a potential of the pixel voltage is applied to the second electrode during at least a part of the preparation section, and a bias voltage is applied between the preparation section and a next preparation section.

Inventors

Jin Zhixu
YIN CHENGWAN

Assignees

韩国睿恩斯有限公司
以友技术有限公司
Qpix解决方案股份有限公司

Dates

Publication Date: 20260508
Application Date: 20241014
Priority Date: 20231101

Claims (10)

1. An X-ray detector as a drive sequence having a repetition standby section, a preparation section, an accumulation section, and a readout section, comprising: a first electrode on the substrate to which the pixel voltage is applied; a layer of an electro-optic substance on the first electrode, and A second electrode on the photovoltaic material layer, Wherein a switching voltage equal to or lower than the potential of the pixel voltage is applied to the second electrode during at least a part of the preparation interval, and a bias voltage is applied between the preparation interval and the next preparation interval.
2. The radiation detector of claim 1, wherein, The switching voltage having the same potential as the pixel voltage is applied to the second electrode during at least a part of the preparation interval.
3. The radiation detector of claim 1, wherein, The switching voltage of a potential lower than the pixel voltage is applied to the second electrode during at least a part of the preparation interval.
4. The radiation detector of claim 1, wherein, The preparation interval includes a first period and a second period, Wherein the switching voltage of a potential lower than the pixel voltage is applied to the second electrode during the first period, After the first period, the bias voltage is applied to the second electrode from the second period until the next preparation interval.
5. The radiation detector of claim 1, wherein, The preparation interval includes a first period and a second period, Wherein a first switching voltage is applied to the second electrode during a first period, and a second switching voltage is applied to the second electrode during the second period after the first period, One of the first and second switching voltages has the same potential as the pixel voltage, and the other of the first and second switching voltages has a potential lower than the pixel voltage.
6. The radiation detector of claim 1, wherein, Alternately applying a first switching voltage and a second switching voltage to the second electrode in the preparation interval, One of the first and second switching voltages has the same potential as the pixel voltage, and the other of the first and second switching voltages has a potential lower than the pixel voltage.
7. The radiation detector of claim 1, wherein, The photovoltaic material layer is formed using a ferroelectric material.
8. The radiation detector of claim 7, wherein, The ferroelectric substance is a perovskite.
9. The radiation detector of claim 8, wherein, The bias voltage has a potential of 0.01 to 0.1V (i.e., 0.01 to 0.1V/. Mu.m) in accordance with the thickness μm of the photoelectric material layer.
10. The radiation detector of claim 8, wherein, The potential of the bias voltage is 1.5-20V.

Description

X-ray detector Technical Field The present invention relates to an X-ray detector. Background Recently, detectors in digital form are widely used for X-ray photography. The X-ray detector is classified into an indirect conversion mode and a direct conversion mode. In the indirect conversion method, X-rays are converted into visible rays by a phosphor, and the visible rays are converted into an electrical signal to be detected. In contrast, in the direct conversion mode, a photoelectric substance (photoconductor) that absorbs X-rays and directly generates an electric signal is used. In the direct conversion mode, a bias voltage is applied to an upper electrode disposed at an upper portion of the photoelectric substance layer, but the bias voltage is constantly maintained at a higher level than a voltage of a pixel voltage applied to a lower electrode disposed at a lower portion of the photoelectric substance layer. This causes a polarization phenomenon in the photoelectric material layer, and charges are trapped. If this polarization phenomenon remains cured for a long period of time, a decrease in sensitivity of X-ray detection may be caused. Disclosure of Invention Technical problem The technical problem of the invention is to provide a scheme capable of relieving polarization phenomenon of an X-ray detector. Technical proposal In order to achieve the above object, the present invention provides an X-ray detector including, as a drive sequence including a repetition standby section, a preparation section, an accumulation section, and a readout section, a first electrode on a substrate to which a pixel voltage is applied, a photoelectric material layer on the first electrode, and a second electrode on the photoelectric material layer, wherein a switching voltage equal to or lower than a potential of the pixel voltage is applied to the second electrode during at least a part of the preparation section, and a bias voltage is applied between the preparation section and a next preparation section. The switching voltage having the same potential as the pixel voltage may be applied to the second electrode during at least a part of the preparation interval. The switching voltage of a potential lower than the pixel voltage may be applied to the second electrode during at least a part of the preparation interval. The preparation interval may include a first period in which the switching voltage of a potential lower than the pixel voltage is applied to the second electrode and a second period in which the bias voltage is applied to the second electrode from the second period until the next preparation interval after the first period. The preparation interval may include a first period in which a first switching voltage is applied to the second electrode and a second period in which a second switching voltage is applied to the second electrode after the first period, one of the first switching voltage and the second switching voltage having the same potential as the pixel voltage, and the other of the first switching voltage and the second switching voltage having a potential lower than the pixel voltage. A first switching voltage and a second switching voltage may be alternately applied to the second electrode in the preparation interval, one of the first switching voltage and the second switching voltage having the same potential as the pixel voltage, and the other of the first switching voltage and the second switching voltage having a potential lower than the pixel voltage. The photovoltaic material layer may be formed using a ferroelectric material. The ferroelectric substance may be a perovskite. The bias voltage may have a potential of 0.01 to 0.1V (i.e., 0.01 to 0.1V/. Mu.m) depending on the thickness μm of the photoelectric material layer. The potential of the bias voltage may be 1.5-20 v. Effects of the invention According to the present invention, in the driving sequence of the X-ray detector, a switching voltage equal to or lower than the pixel voltage is applied to the second electrode as the upper electrode during at least a part of the standby interval, and thereafter, a bias voltage higher than the pixel voltage is applied to the second electrode. Thereby, residual charges in the photoelectric material layer and polarization phenomena can be reduced, thereby alleviating charge trapping. Drawings Fig. 1 is a diagram schematically showing an X-ray detector according to a first embodiment of the present invention. Fig. 2 is a sectional view schematically showing a sensor panel according to a first embodiment of the present invention. Fig. 3 is a diagram schematically showing the timing of switching voltages and bias voltages according to the first embodiment of the present invention. Fig. 4 is a diagram schematically showing the timing of switching voltages and bias voltages according to a second embodiment of the present invention. Fig. 5 is a diagram schematically showing the timing of switching voltage