Neutron transmutation doped natural and isotopically engineered germanium thermistors

Conference · Tue Feb 01 04:00:00 EST 1994

DOI:https://doi.org/10.1117/12.176771· OSTI ID:10148869

Haller, E E; Itoh, K M ^[1]; Beeman, J W; Hansen, W L ^[2]; Ozhogin, V I ^[3]

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1. California Univ., Berkeley, CA (United States). Dept. of Materials Science and Mineral Engineering
2. Lawrence Berkeley Lab., CA (United States)
3. Kurchatov Inst. of Atomic Energy, Moscow (Russia)

We report on the development, fabrication and performance of a new class of thermal sensors for far infrared and millimeter wave detection. These devices consist of small single crystal samples of ultra-pure, natural or isotopically engineered germanium which have been doped by the neutron transmutation doping (NTD) technique. The concentrations of the acceptor and donor dopants (N{sub A},N{sub D}) can be accurately controlled with this technique. They depend on the thermal neutron fluence, the neutron absorption cross sections and the atomic fractions of {sup 70}Ge (for the Ga acceptors) and {sup 74}Ge (for the As donors), respectively. The values of N{sub A} and N{sub D} and their ratio result in a predictable resistivity of the Ge crystals down to temperatures of a few milliKelvin. The excellent control of the resistivity down to very low temperatures, together with the development of ohmic contacts working at the lowest temperatures, allows the fabrication of high sensitivity bolometer arrays with over 100 pixels and highly uniform response.

• Research Organization: Lawrence Berkeley Lab., CA (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States); National Aeronautics and Space Administration, Washington, DC (United States); National Science Foundation, Washington, DC (United States)
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 10148869
• Report Number(s): LBL--34446; CONF-940391--5; ON: DE94011342; CNN: Contract W17605
• Country of Publication: United States
• Language: English

Related Subjects

440500
47 OTHER INSTRUMENTATION
BOLOMETERS
FABRICATION
FAR INFRARED RADIATION
GERMANIUM
RADIOWAVE RADIATION
TELESCOPES
THERMAL INSTRUMENTATION
THERMISTORS