Field Programmable Short Wave Infrared Photodetectors

We propose to advance the state-of-the-art in short wave infrared (SWIR) avalanche photodiodes (APD) to meet NASArsquo;s needs for advancements in star tracking technology. In the Phase I effort, we undertook a feasibility study for development of field programmable SWIR detectors using a PIN-APD architecture with antimonide-based superlattice materials. This study demonstrated that a PIN-APD architecture provides superior signal-to-noise ratio (SNR) at low bias voltage and, with an optimized material, can also provide the best SNR at high bias voltage (with avalanche gain). The goal of the proposed Phasenbsp;II effort is to engineer the process of turning these materials into a focal plane array (FPA). This demonstration will fabricate, passivate, and hybridize a small format array (~256times;256) to a commercially available APD readout integrated circuit (ROIC). This demonstration imager will validate and support NASArsquo;s mission for advancing star tracking by enabling detection of optical communications signals (1550nbsp;nm) and imaging the starfield across the near infrared (NIR) and SWIR.