A Highly Sensitive Multi-element HgCdTe e-APD Detector for IPDA Lidar Applications View Full Text


Ontology type: schema:ScholarlyArticle     


Article Info

DATE

2014-05-10

AUTHORS

Jeff Beck, Terry Welch, Pradip Mitra, Kirk Reiff, Xiaoli Sun, James Abshire

ABSTRACT

An 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 μm cutoff HgCdTe 4 × 4 APD detector array with 80 μm 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 × 4 detector system was characterized at 77 K with a 1.55 μm wavelength, 1 μs 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 σ/mean uniformity of 1.23%. The average, noise-bandwidth normalized, system noise-equivalent power (NEP) was 1.04 fW/Hz1/2 with a σ/mean of 3.8%. The measured, electronics-limited, bandwidth of 6.8 MHz was more than adequate for 1 μs pulse detection. The system had an NEP (3 MHz) of 0.4 fW/Hz1/2 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. More... »

PAGES

2970-2977

References to SciGraph publications

  • 2009-02-24. Performance and Modeling of the MWIR HgCdTe Electron Avalanche Photodiode in JOURNAL OF ELECTRONIC MATERIALS
  • 2008-04-09. A Theoretical Model for the HgCdTe Electron Avalanche Photodiode in JOURNAL OF ELECTRONIC MATERIALS
  • 2011-06-14. History-Dependent Impact Ionization Theory Applied to HgCdTe e-APDs in JOURNAL OF ELECTRONIC MATERIALS
  • 2006-06. The HgCdTe electron avalanche photodiode in JOURNAL OF ELECTRONIC MATERIALS
  • Identifiers

    URI

    http://scigraph.springernature.com/pub.10.1007/s11664-014-3164-8

    DOI

    http://dx.doi.org/10.1007/s11664-014-3164-8

    DIMENSIONS

    https://app.dimensions.ai/details/publication/pub.1030028689


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