MERCURY CADMIUM TELLURIDE JUNCTION FIELD-EFFECT TRANSISTOR FOR IR IMAGING

Each pixel site in HgCdTe consists of not a p-n junction diode, but an n-channel floating gate field-effect transistor in this phase I project. Holes and electrons generated as a result of incoming photons at each pixel site are not sensed directly. The electrons are swept toward the drain and holes are drifted toward the gate and modify the potential at the source. In doing so, it is the amplified signal that is taken from the pixel site which enhances the signal-to-noise ratio in situ. This active pixel sensor concept does not involve in charge transfer. As a result, the stringent material requirements are essentially eliminated. Instead, the current well-developed hgcdte diode technolgoy becomes the foundation of the new focal plane architecture.