Radiation detector, method of operating radiation detector, and method of fabricating radiation detector

A method of operating a radiation detector, wherein the radiation detector comprises a plurality of pixels, wherein a respective one of the plurality of pixels comprises:

• a base substrate;
• a thin film transistor on the base substrate;
• an insulating layer on a side of the thin film transistor away from the base substrate;
• a photosensor on a side of the insulating layer away from the base substrate;
• a passivation layer on a side of the photosensor away from the base substrate;
• a scintillation layer on a side of the passivation layer away from the base substrate;
• and
• a reflective layer on a side of the scintillation layer away from the base substrate;
• wherein the photosensor comprises a first polarity layer in direct contact with the passivation layer, and a second polarity layer connected to a source electrode of the thin film transistor;
• and
• wherein all sides of the first polarity layer other than a side internal to the photosensor are entirely in direct contact with the passivation layer;
• wherein the method comprises:
• providing a bias voltage to the first polarity layer by providing a voltage signal to the reflective layer to achieve the bias voltage at the first polarity layer
• wherein the voltage signal provided to the reflective layer is a first negative voltage;
• the bias voltage provided to the first polarity layer has a second negative voltage;
• and
• an absolute value of the first negative voltage is greater than an absolute value of the second negative voltage.

A method of fabricating a radiation detector having a plurality of pixels;

• wherein fabricating a respective one of the plurality of pixels comprises:
• forming a thin film transistor on a base substrate;
• forming an insulating layer on a side of the thin film transistor away from the base substrate;
• forming a metallic layer on a side of the insulating layer away from the base substrate;
• forming a photosensor on a side of the insulating layer away from the base substrate;
• forming a passivation layer on a side of the photosensor away from the base substrate;
• forming a scintillation layer on a side of the passivation layer away from the base substrate;
• and
• forming a reflective layer on a side of the scintillation layer away from the base substrate;
• wherein forming the photosensor comprises forming a first polarity layer and forming a second polarity layer;
• the first polarity layer is formed to be in direct contact with the passivation layer;
• the second polarity layer is formed to be connected to a source electrode of the thin film transistor;
• wherein all sides of the first polarity layer other than a side internal to the photosensor are entirely in direct contact with the passivation layer;
• wherein forming the metallic layer comprises forming a first part and a second part in a same layer and spaced apart from each other;
• the first part and the second part are formed in a same patterning process using a same mask plate and a same material;
• the first part is formed on a side of the insulating layer away from an active layer of the thin film transistor, and configured to shield light from irradiating on the active layer;
• and
• the second part is formed between the insulating layer and the second polarity layer, is electrically connected to the second polarity layer, and extends through the insulating layer to connect to a source electrode of the thin film transistor.