Two-dimensional Field Shaping for Direct Conversion X-ray Flat Panel Imager: Unipolar Charge Sensing and Avalanche Gain

The detector provides stable avalanche multiplication gain in direct conversion amorphous selenium radiation detectors.


Conventional micropattern gaseous detectors were developed to improve position resolution. However, the range of radiation induced photoelectrons is micrometer to millimeter in, with gas solid-state detectors having three-orders-of magnitude shorter photoelectron range due to their much higher density. Thus, solid-state detectors yield images with substantially higher spatial/temporal resolution. Disordered solids, which are easier and less expensive to develop than single crystalline solids, have not been utilized as photon counting mode detection media because of low carrier mobility and transit-time-limited photo response.

Technology Overview:

Using a direct conversion amorphous selenium radiation detector structure, the detector is able to achieve stable avalanche multiplication gain and provides high‑density insulated wells and fielding shape. These benefits eliminate formation of field hot‑spots and high fields at a metal‑semiconductor interface.


-Lower peak value

-Higher density wells

-More effective in electron blocking


Radiation Therapy

-  cancer Therapy

-  cancer Research

-  cell Research

-  Bio-Medical devices

Intellectual Property Summary:


Stage of Development:


Licensing Potential:

Development partner,Commercial partner,Licensing

Licensing Status:

Available for licensing

Additional Information:

Radiation therapy

Cancer therapy

Cancer research

Cell research

Bio‑medical devices

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