Amorphous selenium detector for tomotherapy and other image-guided radiotherapy systems

A megavoltage radiation detector comprising:

• a radiation source directing megavoltage radiation along a propagation axis;
• a detector positioned to receive the radiation, the detector including a plurality of sheets oriented to extend substantially along the propagation axis and spaced transversely across the axis to define a plurality of axially extending detector volumes, the sheets receive radiation longitudinally and generate high-energetic electrons exiting the material into the detector volumes;
• and
• detection means detecting negatively and positively charged high-energetic particles liberated into the detector volumes to provide for substantially independent signals.

A method of fabricating a megavoltage radiation detector, the method comprising the steps of:

• depositing a plurality of readout electrodes on at least one surface of a substrate;
• depositing an amorphous selenium layer on at least one surface of the readout electrodes;
• and
• depositing a high voltage electrode layer on at least one surface of the amorphous selenium layer.