Recent developments in semiconductor gamma-ray detectors

Abstract

The successful development of lithium-drifted Ge detectors in the 1960's marked the beginning of the significant use of semiconductor crystals for direct detection and spectroscopy of gamma rays. In the 1970's, high-purity Ge became available, which enabled the production of complex detectors and multi-detector systems. In the following decades, the technology of semiconductor gamma-ray detectors continued to advance, with significant developments not only in Ge detectors but also in Si detectors and roomtemperature compound-semiconductor detectors. In recent years, our group at Lawrence Berkeley National Laboratory has developed a variety of gamma ray detectors based on these semiconductor materials. Examples include Ge strip detectors, lithium-drifted Si strip detectors, and coplanar-grid CdZnTe detectors. These advances provide new capabilities in the measurement of gamma rays, such as the ability to perform imaging and the realization of highly compact spectroscopy systems.

Fabrication and characterization of high-purity germanium detectors with amorphous germanium contacts

“…Since the successful development of lithium-drifted Ge detectors introduced the significant use of semiconductor crystals for direct detection and spectroscopy of gamma ray in the 1960s [8][9][10][11][12][13], high-purity Ge (HPGe) detectors gradually became a standard technology to achieve spectroscopy or imaging of gamma rays by providing the best compromise between energy resolution and efficiency for high resolution gamma-ray spectroscopy [14][15][16][17]. A small bandgap energy of Ge (∼ 0.7 eV) creates a large number of electron-hole pairs during interaction with gamma rays, which provides good energy resolution.…”

Neutron Activation Analysis, Atomic Absorption and X‐Ray Fluorescence Spectrometry Review for 2004–2005

“…The most common detector in neutron activation is germanium, the efficiency (volume) of which has increased linearly with time (Luke et al 2005); despite this, improved resolution does not seem to be likely for Ge detectors in the near future. An interesting detector that is being developed is the coplanar-grid CdZnTe, which runs at room temperature, but does not yet have the resolution of Ge detectors (Luke et al 2005). Provided they manage to bring their resolution to the same level as Ge detectors, CdZnTe detectors would reduce to almost zero the running cost of the detection unit of NAA laboratories.…”

Implementation of a wristwatch for dose measurement based on CsI detector

“…However, GM tubes have a large volume, high operating voltage, lower accuracy, and poor linear energy response [1] . Semiconductor detectors have lower detection efficiency and poor energy response [2] [3] . Scintillation detectors are typically used with photomultiplier tubes (PMT), which have a large volume and require a high-voltage power supply [4] .…”