CMOS infrared sensors with giant internal signal amplification

Theoretical model of a new high-speed metal - insulator - semiconductor (MIS) radiation sensor possessing giant internal signal amplification is proposed to describe the experimentally obtained results. The sensor is fabricated on an Ultra-High Resistivity (UHR) Epi Layer (>10 kΩ cm) on a heavily doped wafer. Theoretical modeling explains the giant value of the internal amplification of the signal that is determined as the ratio of peak values of readout currents and instantaneous photo current. At the integration time about 1 sec the amplification coefficient is of the order of 104 in the case of the external load 10 - 50 kΩ, and it is of the order of 106 when the external load is smaller than 1 kΩ. The sensors operate under non-modulated radiation as well as under an optical signal modulation till 1 GHz.