Development of three-dimensional position-sensitive room temperature semiconductor gamma-ray spectrometers

Journal Article · Sat Jul 01 04:00:00 EDT 2000 · Transactions of the American Nuclear Society

OSTI ID:20093644

He, Z; Li, W; Knoll, G F; Wehe, D K

Semiconductor detectors can provide better spectroscopic performance than scintillation or gas-filled detectors because of the small ionization energy required to generate each electron-hole pair. Indeed, cryogenically cooled high-purity germanium detectors have played the dominant role whenever the best gamma-ray spectroscopy is required. A decades-long search for other semiconductor detectors that could provide higher stopping power and could operate at room temperature has been ongoing. Wide-band-gap semiconductors, such as CdTe, CdZnTe, and HgI{sub 2}, have captured the most attention. However, the use of these semiconductors in detectors has been hindered primarily by problems of charge trapping and material nonuniformity. Introduced in 1994, single-polarity charge sensing on semiconductor detectors has shown great promise in avoiding the hole-trapping problem, and the newly demonstrated three-dimensional position-sensing technique can significantly mitigate the degradation of energy resolution due to the nonuniformity of detector material. In addition, three-dimensional position sensitivity will provide unique imaging capabilities of these gamma-ray spectrometers. These devices are of interest for nuclear nonproliferation, medical imaging, gamma-ray astronomy, and high-energy physics applications. This paper reports the latest results using second-generation three-dimensional position-sensitive semiconductor spectrometers. The improvements over the first generation devices include: (1) Larger volume; (2) Improved anode design; (3) More reliable connections; (4) Enhanced electronic capability; and (5) Measurement of electron drift times. The new detectors and readout electronics (from IDE AS) are being assembled and tested.

• Research Organization: Univ. of Michigan, Ann Arbor, MI (US)
• OSTI ID: 20093644
• Journal Information: Transactions of the American Nuclear Society, Journal Name: Transactions of the American Nuclear Society Vol. 82; ISSN 0003-018X; ISSN TANSAO
• Country of Publication: United States
• Language: English

Related Subjects

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
AMBIENT TEMPERATURE
DESIGN
GAMMA SPECTROMETERS
PERFORMANCE
POSITION SENSITIVE DETECTORS
SEMICONDUCTOR DETECTORS