Patent Publication Number: US-2022221598-A1

Title: Circuit for sensing x-ray

Description:
BACKGROUND 
     Technical Field 
     The present disclosure relates to a circuit for sensing an electromagnetic ray, and particularly relates to a circuit for sensing an X-ray. 
     Description of Related Art 
     With the rapid development of electronic products, sensors are employed in a variety of electronic devices or systems. Sensors such as photodetectors sensitive to visible lights or other electromagnetic rays (for example, a gamma ray, an X-ray, an ultraviolet light, an infrared light, etc.) are particularly useful for image capturing in radiation medicine, animal experiments, industrial non-destructive testing, etc. The photodetector imaging devices are constantly improved for their image quality and reliability. 
     SUMMARY 
     The present disclosure provides a circuit for sensing an X-ray with improved quality or reliability. 
     According to an embodiment of the present disclosure, a circuit for sensing an X-ray includes a switching element, a storage element, a sensing element, and a branching element. The storage element electrically coupled to the switching element. The sensing element electrically coupled to the switching element. The branching element electrically coupled between the storage element and the sensing element. 
     To make the aforementioned more comprehensible, several embodiments accompanied with drawings are described in detail as follows. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings are included to provide a further understanding of the disclosure, and are incorporated in and constitute a part of this specification. The drawings illustrate exemplary embodiments of the disclosure and, together with the description, serve to explain the principles of the disclosure. 
         FIG. 1  is a schematic top view of an X-ray device in an embodiment of the present disclosure. 
         FIG. 2  is a circuit diagram of a circuit for sensing X-ray in a pixel structure of the X-ray device of  FIG. 1 . 
         FIG. 3  is a circuit diagram of a circuit for sensing X-ray in a pixel structure in another embodiment of the present disclosure. 
         FIG. 4A  is a circuit diagram of a structure of the branching element in another embodiment of the present disclosure. 
         FIG. 4B  is a schematic diagram of the branching element in another embodiment of the present disclosure. 
         FIG. 4C  is a schematic diagram of the branching element in yet another embodiment of the present disclosure. 
         FIG. 4D  is a schematic diagram of the branching element in yet another embodiment of the present disclosure. 
         FIG. 5  is a flowchart of an embodiment of a method of driving the X-ray circuit for sensing the X-ray. 
     
    
    
     DESCRIPTION OF THE EMBODIMENTS 
     Some words are used to refer to specific components in the whole specification and the appended claims in the present disclosure. A person skilled in the art should understand that an electronic device manufacturer may use different names to refer to the same components. This specification is not intended to distinguish components that have the same functions but different names. In this specification and the claims, words such as “include”, “comprise”, and “have” are open words, and should be interpreted as “including, but not limited to”. Therefore, when terms “include”, “comprise”, and/or “have” are used in the description of the present disclosure, the presence of corresponding features, regions, steps, operations and/or components is specified without excluding the presence of one or more other features, regions, steps, operations and/or components. 
     The directional terms mentioned herein, such as “above”, “below”, “front”, “back”, “left”, and “right”, refer to the directions in the accompanying drawings. Therefore, the directional terms are only used for illustration instead of limiting the present disclosure. In the accompanying drawings, common features of a method, a structure and/or a material used in a specific embodiment are shown in the drawings. However, these drawings should not be construed as defining or limiting the scope or nature of these embodiments. For example, the relative sizes, thicknesses and positions of films, regions and/or structures may be reduced or enlarged for clarity. 
     It should be understood that, when a component or a film is referred to as being “connected to” another component or film, it may be directly connected to another component or film, or there are components or films inserted between the two components or films. When a component or a film is referred to as being “directly connected to” another component or film, there is no component or film inserted between the two components or films. In addition, when a component is referred to as being “coupled to another component (or a variant thereof)”, it may be directly connected to another component, or may be indirectly connected to (for example, electrically connected to) the another component through one or more components. 
     The term “approximately”, “equal to”, “the same as”, “substantially” or “roughly” is generally interpreted as being within 20% of a given value or range, or interpreted as being within 10%, 5%, 3%, 2%, 1% or 0.5% of a given value or range. 
     A structure (or layer, component, substrate) being located on another structure (or layer, component, substrate) described in the present disclosure may mean that two structures are adjacent and directly connected, or may mean that two structures are adjacent and indirectly connected. Indirect connection means that there is at least one intermediate structure (or intermediate layer, intermediate component, intermediate substrate, intermediate spacing) between two structures, the lower surface of a structure is adjacent or directly connected to the upper surface of the intermediate structure, and the upper surface of the other structure is adjacent or directly connected to the lower surface of the intermediate structure. The intermediate structure may be a single-layer or multi-layer physical structure or non-physical structure, which is not limited. In the present disclosure, when a structure is on or disposed “on” another structure, it may mean that a structure is “directly” disposed on another structure, or a structure is “indirectly” disposed on another structure, that is, at least one structure is sandwiched between a structure and another structure. 
     The terms such as “first”, “second”, and the like in this specification may be used for describing various elements, components, areas, layers, and/or parts, but the elements, components, areas, layers, and/or parts are not limited by such terms. The terms are only used to distinguish one element, component, area, layer, or part from another element, component, area, layer, or part. Therefore, a “first component”, “first element”, “first region”, “first layer”, or “first part” discussed below is used to distinguish it from a “second component”, “second element”, “second region”, “second layer”, or “second part”, and is not used to define an order or a specific component, element, region, layer and/or part. 
     In the present disclosure, various embodiments described below may be used in any combination without departing from the spirit and scope of the present disclosure, for example, some features of one embodiment may be combined with some features of another embodiment to form another embodiment. 
     Exemplary embodiments of the present disclosure are described in detail, and examples of the exemplary embodiments are shown in the accompanying drawings. Whenever possible, the same component symbols are used in the drawings and descriptions to indicate the same or similar parts. 
       FIG. 1  is a schematic top view of an X-ray device in an embodiment of the present disclosure.  FIG. 2  is a circuit diagram of a circuit for sensing an X-ray in a pixel structure of the X-ray device of  FIG. 1 . Referring to  FIG. 1  and  FIG. 2 , the X-ray device  10  according to an embodiment may include a plurality of pixel structures PX. The pixel structures PX may be arranged into an array disposed on a substrate  100 . Each of the pixel structures PX may include a circuit  101  for sensing an X-ray. The circuit  101  may include a switching element  110 , a storage element  120 , a sensing element  140  and a branching element  130 . In some embodiments, the storage element  120  is electrically coupled to the switching element  110 . The sensing element  140  is electrically coupled to the switching element  110 . According to an embodiment, the branching element  130  is electrically coupled between the storage element  120  and the sensing element  140 . In other words, the switching element  110  is electrically coupled to the storage element  120 , the branching element  130 , and the sensing element  140 . The switching element  110  has a first terminal  111  (may be referred to as a control terminal), a second terminal  112  and a third terminal  113 . The storage element  120  has a first terminal  121 . The first terminal  121  of the storage element  120  is electrically coupled to the third terminal  113  of the switching element  110 , a first terminal  131  of the branching element  130 , and a first terminal  141  of the sensing element  140 . Under the above configurations, a first voltage V 1  at the storage element  120  may be substantially the same as a bias voltage VB at the second terminal  132  of the branching element  130 . Thus, the X-ray device  10  may have better image quality, or improved reliability. 
     According to an embodiment, the pixel structures PX are disposed on the substrate  100  along a first axis X (i.e. x-axis) and a second axis Y (i.e. y-axis) in a grid-like array, but not limited thereto. The substrate  100  may include, for example, a rigid substrate or a flexible substrate. For example, a material of the substrate  100  include glass, quartz, sapphire, ceramic, polycarbonate (PC), polyimide (PI), polyethylene terephthalate (PET), other suitable substrate materials, or a combination of the above, but is not limited thereto. In some embodiments, the substrate  100  includes a printed circuit board (PCB). 
     According to an embodiment, the X-ray device  10  further includes signal circuits (not shown) disposed on the substrate  100 . For examples, the signal circuits include a scan line, a data line, a power line and other suitable circuits, but not limited thereto. In some embodiments, the scan lines and the data lines are disposed along the x-axis and y-axis, and interweaving into a grid, but the embodiment is not limited thereto. The material of the signal circuits may include molybdenum (Mo), titanium (Ti), aluminum (Al), tantalum (Ta), niobium (Nb), hafnium (HO, nickel (Ni), chromium (Cr), cobalt (Co), zirconium (Zr), tungsten (W), other suitable metals, or alloys or combinations of the above materials, but the embodiment is not limited thereto. 
     Referring to  FIG. 2 , each of the pixel structures PX includes the circuit  101 . The circuit  101  may include the switching element  110  having a plurality of terminals. The switching element  110  may be a thin film transistor (TFT) or any other suitable active device. The switching element  110  includes the first terminal  111  (may also be referred as the control terminal), the second terminal  112  and the third terminal  113 . In some embodiments, the first terminal  111  may be a gate electrode and may be electrically coupled to the scan line. That is to say, the first terminal  111  (e.g. the control terminal) is electrically coupled to a scan signal SN through the scan line. The second terminal  112  may be a source electrode and may be electrically coupled to the data line (not shown). According to some embodiments, the second terminal  112  may optionally couple to a circuit component (not shown). The circuit component may be a readout integrated circuit, but the embodiment is not limited thereto. That is to say, the second terminal  112  is electrically coupled to a readout signal RO. The third terminal  113  may be a drain electrode and may be electrically coupled to the storage element  120 , the branching element  130 , and the sensing element  140 . 
     In some embodiments, the switching element  110  may include a semiconductor material, such as amorphous silicon, poly-silicon, low temperature poly-silicon (LTPS), or metal oxide, but not limited thereto. The switching element  110  may be a top gate, a bottom gate, or a dual gate TFT, but the embodiment is not limited thereto. 
     Referring to  FIG. 2  again, the third terminal  113  of the switching element  110  is coupled to the storage element  120 , the branching element  130  and the sensing element  140  at a node N 1 . Specifically, a first terminal  121  of the storage element  120  is electrically coupled to the third terminal  113  of the switching element  110  at the node N 1 . A second terminal  122  of the storage element  120  may be coupled to a reference signal V Ref . The reference signal V Ref  may be a ground signal, but not limited thereto. In the illustrated embodiment, the storage element  120  may include a capacitor, but not limited thereto. 
     In some embodiments, the first terminal  141  of the sensing element  140  is coupled to the first terminal  121  of the storage element  120  and the third terminal  113  of the switching element  110  at the node N 1 . The sensing element  140  includes a photoconductor or a photodiode. The sensing element  140  may be adapted to receive electromagnetic radiations such as X-ray radiation to generate charges. Specifically, the sensing element  140  may be provided with a voltage from a voltage supply (not shown), and when the sensing element receives an external X-ray, the sensing element  140  may generate an induced charge, an electrically current, or a signal. The signal provided or outputted by the sensing element  140  may have the first voltage V 1  (may also be referred as a sensing voltage). The first voltage V 1  may be detected at the node N 1 , but not limited thereto. In the illustrated embodiment, the sensing element  140  is a photoconductor capable of sensing the X-ray according to an electromagnetic induction effect. In some other embodiments, the sensing element  140  also includes a photoconductor used for sensing other visible lights or invisible lights, but not limited thereto. 
     In some embodiments, the sensing element  140  may include amorphous selenium (a-Se). In some other embodiments, the sensing element  140  may further include silicon, germanium, thallium bromide, or other suitable semiconductor materials, but not limited thereto. 
     It should be noted that a first terminal  131  of the branching element  130  is coupled to the third terminal  113  of the switching element  110 , the first terminal  121  of the storage element  120 , and the first terminal  141  of the sensing element  140  at the node N 1 . In some of the embodiments, the branching element  130  may include a switch component or a diode, or a combination thereof, but not limited thereto. In some embodiments, the branching element  130  may also include a plurality of interconnected diodes, but not limited thereto. In the illustrated embodiment, the branching element  130  is coupled between the storage element  120  and the sensing element  140 , but the limited thereto. In some other embodiments, the branching element  130  is coupled between the switching element  110  and the storage element  120 , or coupled between the switching element  110  and the sensing element  140 . The second terminal  132  of the branching element  130  may be electrically coupled to a bias signal with the bias voltage VB. In some embodiments, the bias signal may be provided by a bias source. In some embodiments, the first terminal  131  of the branching element  130  may be an anode, and the second terminal  132  of the branching element  130  may be a cathode, but the disclosure is not limited thereto. 
     Under the above configurations, the branching element  130  (such as a diode) may be used to provide a first diverting current D 1  so as to decrease the voltage level at node N 1 . Specifically, when the sensing element  140  receives the X-ray, the induced charges may be generated by the sensing element  140  and provides the first voltage V 1  at the node N 1 . The first terminal  121  of the storage element  120  may serve as a charge collecting electrode (CCE) and collect or store the charges generated by the sensing element  140 . The readout integrated circuit may be electrically coupled to the switching element  110  at the second terminal  112 , and may then perform a readout function to read the stored charges (may be referred as the readout signal RO) provided by the storage element  120 , or perform a reset function. Therefore, the X-ray device  10  may be used for X-ray imaging functions. 
     When the sensing elements  140  receiving a higher intensity X-ray radiation (e.g. where the pixel structures PX are not shielded by any object such as a human body), the generation of excessive charges may be generated at the node N 1 . That is to say, the first voltage V 1  may contribute to the increase of a voltage of the storage element  120 , and the voltage of the storage element  120  may be increased to be greater than the bias voltage VB. Prolong exposure to high voltage level may cause deterioration of the switching element  110  or may reduce the lifespan of the switching element  110 . 
     It should be noted that, when the voltage of the storage element  120  at the node N 1  is greater than the bias voltage VB from the bias signal, the first diverting current D 1  may be formed across the branching element  130 . Specifically, the first diverting current D 1  may flow from the first terminal  131  of the branching element  130  to the second terminal  132  of the branching element  130 , so that the voltage of the storage element  120  at the node N 1  may be decreased. That is to say, the first voltage V 1  (for example, a sensing voltage which is outputted from the sensing elements  140 ) is diverted by the branching element  130  when the voltage of the storage element  120  is greater than the bias voltage VB. Therefore, the voltage of the storage element  120  may be maintained at a substantially similar level as the bias voltage VB. Based on the above, when the switching element  110  is turned on (i.e. the switching element  110  is conductive), the risks of damaging the switching element  110  by a larger current flowing into the switching element  110  may be reduced. The larger current may be generated by a larger voltage difference. Based on the above, the high voltage level at node N 1  caused by the excessive charges may be prevented. So that, the quality or the reliability of the X-ray device  10  may be improved. 
       FIG. 3  is a circuit diagram of a circuit for sensing X-ray in a pixel structure in another embodiment of the present disclosure. The pixel structure PX′ of the present embodiment is substantially similar to the pixel structure PX in  FIG. 2 , and thus the same or similar components in the two embodiments are omitted herein. The present embodiment is different from the pixel structure PX in that: in the circuit  101 ′, the second terminal  132  is electrically coupled to the node N 1 , and the first terminal  131  is electrically coupled to the bias signal with the bias voltage VB. The first terminal  131  may be an anode, and the second terminal  132  may be a cathode. 
     Under the above configurations, the branching element  130  may be used to provide a second diverting current D 2 . Specifically, when the voltage of the storage element  120  at the node N 1  is less than the bias voltage VB from the bias signal, the second diverting current D 2  may be formed across the branching element  130 . The second diverting current D 2  may flow in a direction from the first terminal  131  to the second terminal  132 . In other words, a portion of charges which generated by the sensing element  140  may flow through the first terminal  131  and the second terminal  132 , thus increasing the second voltage V 2  at the node N 1 . Therefore, the voltage of the storage element  120  may be increased or maintained at a substantially similar level as the bias voltage VB. Based on the above, the voltage values may be balanced, or kept at a desired value which is a safety value that the switching element  110  would not be damaged. For example, the safety value may be substantially the same as the bias voltage VB. The X-ray device  10  has improved quality or reliability. 
       FIG. 4A  is a circuit diagram of a structure of the branching element in another embodiment of the present disclosure. The branching element  130 A may be a switch component for example a thin-film transistor (TFT) including a plurality of terminals, such as a control terminal T 1 , a second terminal T 2 , and a third terminal T 3 . The control terminal T 1  may be a gate electrode. The second terminal T 2  may be a source electrode. The third terminal T 3  may be a drain electrode. The control terminal T 1  and the second terminal T 2  is coupled at a node N 3 . The node N 3  may be electrically coupled to the node N 1  as shown in  FIG. 2  or  FIG. 3 . In some embodiments, the node N 3  coupled between the sensing element  140  and the storage element  120  as shown in  FIG. 2  or  FIG. 3 . The third terminal T 3  is electrically coupled to the bias signal as shown in  FIG. 2  or  FIG. 3  in a similar fashion as the second terminal  132 . The control terminal T 1  may be electrically coupled to the second terminal T 2 . Therefore, when the first voltage V 1  is larger than bias voltage VB, the control terminal T 1  may turn on the branching element  130 A and form the first diverting current D 1  or the second diverting current D 2  (as shown in  FIG. 2  or  FIG. 3 ). The another portion of the charges as mentioned above may flow through the node N 3  to the third terminal T 3  of the branching element  130 A. Based on the above, the high voltage level at node N 1  (as shown in  FIG. 2  or  FIG. 3 ) caused by the excessive charges may be decreased. The X-ray device has improved the quality or the reliability. 
       FIG. 4B  is a schematic diagram of the branching element in another embodiment of the present disclosure. In the illustrated embodiment, the branching element  130 B may be a diode. The diode may be a PIN diode. For example, the branching element  130 B may include a first doped layer  1301 , an intrinsic layer  1302 , and a second doped layer  1303  opposite to the first doped layer  1301 . The intrinsic layer  1302  is between the first doped layer  1301  and the second doped layer  1303 . In some embodiment, the intrinsic layer  1302  may include silicon, but not limited thereto. The first doped layer  1301  may include a p-type semiconductor. For example, the p-type semiconductor is an intrinsic semiconductor (such as silicon) doped with Group III elements such boron, aluminum, gallium, or indium. The second doped layer  1303  may include a n-type semiconductor. For example. the n-type semiconductor is an intrinsic semiconductor (such as silicon) doped with Group V elements such as phosphorus, arsenic, antimony, or bismuth. In some other embodiments, lithium may also be used as a dopant to form the n-type semiconductor. 
     In some embodiments, the first doped layer  1301  may be electrically coupled to the first terminal  131  of the branching element  130 B, and the second doped layer  1303  may be electrically coupled to the second terminal  132  of the branching element  130 B. For example. the first terminal  131  is the anode, and the second terminal  132  is the cathode. Under the above configuration, the first doped layer  1301  is electrically coupled to the first terminal  131  of the branching element  130 B at the node N 1  (shown in  FIG. 2 ), and the second doped layer  1303  is electrically coupled to the second terminal  132  of the branching element  130 B, which may be coupled to the bias signal with the bias voltage VB. When the voltage of the storage element  120  is larger than the bias voltage VB, electron-hole pairs are formed in the intrinsic layer  1302  thus reducing the electrical resistance in the intrinsic layer  1302 . The first diverting current D 1  is formed, thus a portion of the charges generated by the sensing element  140  may be diverted. In other word, the portion of the charges may flow through the first terminal  131 , the first doped layer  1301 , the intrinsic layer  1302 , and the second doped layer  1303 . Another portion of the charges generated by the sensing element  140  may be stored in the storage element  120 . Therefore, the voltage of the storage element  120  may be decreased or maintained at a substantially similar level as the bias voltage VB. Based on the above, the voltage may be balanced, or kept at a desired voltage. The high voltage level at the node N 1  (as shown in  FIG. 2  or  FIG. 3 ) caused by the excessive charges may be decreased. The X-ray device has improved the quality or the reliability. 
       FIG. 4C  is a schematic diagram of the branching element in yet another embodiment of the present disclosure. In the illustrated embodiment, the branching element  130 C may be a diode. The branching element  130 C of the present embodiment is substantially similar to the branching element  130 B in  FIG. 4B , and thus the same and similar components in the two embodiments are omitted herein. The present embodiment is different from the branching element  130 B in that the branching element  130 C may be a PN diode. For example. the branching element  130 C may include a first doped layer  1301  and a second doped layer  1303 . The first doped layer  1301  may contact the second doped layer  1303 . The first doped layer  1301  may include the p-type semiconductor. The second doped layer  1303  may include the n-type semiconductor. An interface  1305  of the first doped layer  1301  and the second doped layer  1303  may be a p-n junction. 
     In some embodiments, the first doped layer  1301  may be electrically coupled to the first terminal  131  of the branching element  130 C, and the second doped layer  1303  may be electrically coupled to the second terminal  132  of the branching element  130 C. For example. the first terminal  131  is the anode, and the second terminal  132  is the cathode. Under the above configuration, the first doped layer  1301  is electrically coupled to the first terminal  131  of the branching element  130 C at the node N 1  (shown in  FIG. 2 ), and the second doped layer  1303  is electrically coupled to the second terminal  132  of the branching element  130 C, which may be coupled to the bias signal with the bias voltage VB. When the voltage of the storage element  120  is larger than the bias voltage VB, electron-hole pairs may be formed in the branching element  130 C, for example, the electron-hole pairs may be formed at the interface  1305 . The first diverting current D 1  is formed, thus a portion of the charges generated by the sensing element  140  may be diverted. In other word, the portion of the charges may flow through the first terminal  131 , the first doped layer  1301 , the intrinsic layer  1302 , and the second doped layer  1303 . Another portion of the charges generated by the sensing element  140  may be stored in the storage element  120 . Therefore, the voltage of the storage element  120  may be decreased or maintained at a substantially similar level as the bias voltage VB. The high voltage level at the node N 1  (as shown in  FIG. 2  or  FIG. 3 ) caused by the excessive charges may be decreased. The X-ray device has improved the quality or the reliability. 
       FIG. 4D  is a schematic diagram of the branching element in yet another embodiment of the present disclosure. In the illustrated embodiment, the branching element  130 D may be a diode. The branching element  130 D of the present embodiment is substantially similar to the branching element  130 C in  FIG. 4C , and thus the same or similar components in the two embodiments are omitted herein. The present embodiment is different from the branching element  130 C in that the branching element  130 D may be a Schottky diode. For example. the branching element  130 D may include a metal layer  1304  and a second doped layer  1303 . The metal layer  1304  may contact the second doped layer  1303 . The metal layer  1304  may include molybdenum, platinum, chromium, or tungsten. In some other embodiments, the metal layer may also include silicides, such as palladium silicide or platinum silicide, but not limited thereto. The second doped layer  1303  may include the n-type semiconductor. 
     In some embodiments, the metal layer  1304  is electrically coupled to the first terminal  131  of the branching element  130 D, and the second doped layer  1303  may be electrically coupled to the second terminal  132  of the branching element  130 D. For example. the first terminal  131  is the anode, and the second terminal  132  is the cathode. Under the above configuration, the metal layer  1304  is electrically coupled to the first terminal  131  of the branching element  130 D at the node N 1  (shown in  FIG. 2 ), and the second doped layer  1303  is electrically coupled to the second terminal  132  of the branching element  130 D, which may be coupled to the bias signal with the bias voltage VB (shown in  FIG. 2 ). As shown in  FIG. 2  and  FIG. 4D , when the voltage of the storage element  120  is larger than the bias voltage VB, electron-hole pairs are formed in the second doped layer  1303 . The first diverting current D 1  is formed, thus a portion of the charges generated by the sensing element  140  may be diverted. In other word, the portion of the charges may flow through the first terminal  131 , the first doped layer  1301 , the intrinsic layer  1302 , and the second doped layer  1303 . Another portion of the charges generated by the sensing element  140  may be stored in the storage element  120 . Therefore, the voltage of the storage element  120  may be decreased or maintained at a substantially similar level as the bias voltage VB. Based on the above, the voltage may be balanced, or kept at a desired voltage. The high voltage level at the node N 1  caused by the excessive charges may be decreased. The X-ray device has improved the quality or the reliability. 
       FIG. 5  is a flowchart of an embodiment of a method of driving the X-ray circuit for sensing the X-ray. A brief description of a method of driving the X-ray circuit  101  for sensing the X-ray is described hereinafter. In Step S 101 , the X-ray circuit  101  for sensing the X-ray as shown in  FIG. 2  is provided. 
     In Step S 101 - 1 , the first terminal  121  of the storage element  120  is coupled to the first terminal  131  of the branching element  130 . 
     In Step S 102 , the bias signal with the bias voltage VB coupled to the branching element  130  is provided. In some embodiments, the bias voltage VB coupled to the second terminal of the branching element  130  is provided. 
     In Step S 102 - 1 , the reference signal V Ref  is provided to the second terminal  122  of the storage element  120 . 
     In Step S 103 , the X-ray is received by the sensing element  140  and being outputted as the sensing voltage (e.g. the first voltage V 1 ). 
     In Step S 104 , the sensing voltage is diverted by the branching element  130  when an absolute value of the voltage of the storage element  120  is greater than an absolute value of the bias voltage. In detail, the first diverting current D 1  may be generated and flow through the first terminal  131  of the branching element  130  and the second terminal  132  of the branching element  130  to divert the sensing voltage. For example, the first diverting current D 1  may flow from the first terminal  131  of the branching element  130  to the second terminal  132  of the branching element  130 . In other word, a portion of the charges which generate the sensing voltage may be diverted to the branching element  130 . Another portion of the charges may flow to the storage element  120  and may be stored in the storage element  120 . A readout voltage corresponding to the another portion of the charges as mentioned above may be outputted by the storage element  120 . In some embodiment, the readout voltage may be generated by the another portion of the charges as mentioned above, but not limited thereto. 
     In Step  104 - 1 , a charge corresponding to the readout voltage is stored in the storage element  120 . 
     In Step S 105 , the switching element  110  may be turned on after diverting the sensing voltage. In detail, the scan signal SN may be transmitted to the control terminal  111  of the switching element  110  which electrically coupled to the scan signal SN, and the switching element  110  is turned on. In some embodiments, the absolute value of the voltage of the storage element  120  is substaintially equal to the absolute value of the bias voltage before the Step S 105 . So that, the probability of damaged the switching element  110  by the higher voltage may be decreased when turning on the switching element  110 . 
     In Step S 106 , the readout voltage outputted by the storage element  120  is outputted to the switching element  110 . In other word, the readout voltage may cause a readout current flowing through the third terminal  113  of the switching element  110  and the second terminal  112  of the switching element  110 . The readout current at the second terminal  112  may be the readout signal RO, and may be read by the circuit component. According to the above, higher voltage level caused by the excessive charges may be decreased. The method of driving the X-ray circuit  101  for sensing the X-ray may provide improving the quality or the reliability. 
     Based on the above, the x-ray device of the embodiment of the present disclosure includes the branching element coupled to the switching element, and the branching element is coupled between the storage element and the sensing element. When the voltage at first terminal of the branching element and the second voltage value at the second terminal of the branching element are different (such as the voltage of the storage element is different from the bias voltage), the diverting current may be formed across the branching element. The sensing voltage from the sensing element may flow from the first terminal of the branching element to the second terminal of the branching element thus diverting the sensing voltage, or decreasing the voltage of the storage element to be substantially the same as the bias voltage. Or in another embodiment, the voltage of the storage element may be increased to be substantially the same as the bias voltage. Therefore, the voltage of the storage element may be maintained at a substantially similar level as the bias voltage. According to the above, the higher voltage level caused by the excessive charges may be decreased. The circuit for sensing the X-ray has improved the quality or the reliability. The method of driving the X-ray circuit for sensing the X-ray provides improved the quality or the reliability. 
     It will be apparent to those skilled in the art that various modifications and variations can be made to the disclosed embodiments without departing from the scope or spirit of the disclosure. In view of the foregoing, it is intended that the disclosure covers modifications and variations provided that they fall within the scope of the following claims and their equivalents.