N/A

High performance NIR APDs suitable for photon counting are presently unavailable. New high sensitivity, high speed photodetectors operating from 1.0 to 1.6 microns are needed for both military and commercial applications. New research has demonstrated APD structures, which use a Si multiplication region and an InGaAs absorption region. This device shows high sensitivity, very high speed, low noise and high temperature and voltage stability. However, the developed for high speed 1540 nm optical fiber communication, specifically high GB product, these APDs have high dark current (dark count) and low gain (10-20) and are not suited for lower speed photon counting applications. Our Phase I research identified new detector architectures suitable for photon counting:. These detectors provide high internal gain (50-500) and low dark current. The high gain can be achieved at relatively low bias (below breakdown) such that photon counting is possible without passive or active quenching. On Phase II, we propose to fabricate the NIR photodiodes and monolithically integrate these detectors with low noise CMOS readouts by a new epitaxial layer process and calibrate the detectors at NIST facilities.