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A Highly Sensitive Multi-Element HgCdTe E-APD Detector for IPDA Lidar ApplicationsAn HgCdTe electron avalanche photodiode (e-APD) detector has been developed for lidar receivers, one application of which is integrated path differential absorption lidar measurements of such atmospheric trace gases as CO2 and CH4. The HgCdTe APD has a wide, visible to mid-wave-infrared, spectral response, high dynamic range, substantially improved sensitivity, and an expected improvement in operational lifetime. A demonstration sensor-chip assembly consisting of a 4.3 lm cutoff HgCdTe 4 9 4 APD detector array with 80 micrometer pitch pixels and a custom complementary metal-oxide-semiconductor readout integrated circuit was developed. For one typical array the APD gain was 654 at 12 V with corresponding gain normalized dark currents ranging from 1.2 fA to 3.2 fA. The 4 9 4 detector system was characterized at 77 K with a 1.55 micrometer wavelength, 1 microsecond wide, laser pulse. The measured unit gain detector photon conversion efficiency was 91.1%. At 11 V bias the mean measured APD gain at 77 K was 307.8 with sigma/mean uniformity of 1.23%. The average, noise-bandwidth normalized, system noise-equivalent power (NEP) was 1.04 fW/Hz(exp 1/2) with a sigma/mean of 3.8%. The measured, electronics-limited, bandwidth of 6.8 MHz was more than adequate for 1 microsecond pulse detection. The system had an NEP (3 MHz) of 0.4 fW/Hz(exp 1/2) at 12 V APD bias and a linear dynamic range close to 1000. A gain-independent quantum-limited SNR of 80% of full theoretical was indicative of a gain-independent excess noise factor very close to 1.0 and the expected APD mode quantum efficiency.
Document ID
Document Type
Reprint (Version printed in journal)
Beck, Jeff
(DRS Infrared Technologies Dallas, TX, United States)
Welch, Terry
(DRS Infrared Technologies Dallas, TX, United States)
Mitra, Pradip
(DRS Infrared Technologies Dallas, TX, United States)
Reiff, Kirk
(Analog/Digital Integrated Circuits, Inc. Longwood, FL, United States)
Sun, Xiaoli
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Abshire, James
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Date Acquired
June 17, 2015
Publication Date
May 10, 2014
Publication Information
Publication: Journal of Electronic Materials
Volume: 43
Issue: 8
ISSN: 0361-5235
Subject Category
Instrumentation And Photography
Report/Patent Number
Distribution Limits
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