22 November 1986 Extrinsic Germanium Photoconductor Material: Crystal Growth and Characterization
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Proceedings Volume 0659, Materials Technologies for Infrared Detectors; (1986) https://doi.org/10.1117/12.938559
Event: 1986 International Symposium/Innsbruck, 1986, Innsbruck, Austria
Ge:Ga and Ge:Be extrinsic photoconductors are used in the 50 - 200 and 30 - 50 μm wave-length range respectively as optimized detectors for far-infrared astronomy applications. Reproducible materials synthesis and comprehensive materials characterization are required for the development of focal plane detectors which reach the high sensitivity which is theoretically possible under the very low background flux conditions of space-based observation. Ge:Ga, Ge:Be, and Ge:Zn photoconductor materials have been grown using the Czochralski technique under high purity conditions. Residual impurities can be controlled to levels of~1010 cm -3, leading to greater control of free carrier lifetime and mobility, and more reproducible detector performance. Characterization of the material with variable temperature Hall effect and infrared spectroscopy shows that Be and Zn doped crystals grown under a H2 atmosphere can contain hydrogen related complexes which affect detector performance by decreasing the resistivity of the material at low temperatures. The growth of Ge:Be presents a special case in which the oxygen content of the melt environment is a critical factor in determining reproducibility of Be doping and device performance.
© (1986) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Nancy M Haegel, Nancy M Haegel, Eugene E Haller, Eugene E Haller, } "Extrinsic Germanium Photoconductor Material: Crystal Growth and Characterization", Proc. SPIE 0659, Materials Technologies for Infrared Detectors, (22 November 1986); doi: 10.1117/12.938559; https://doi.org/10.1117/12.938559

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