Search

Thallium bromide (TlBr) has been under development for room temperature gamma ray spectroscopy. As a result of improvements in material processing and detector fabrication over the last several years, the electron and hole mobility-lifetime products of TlBr are close to those of CdTe. This has allowed us to fabricate 10 mm thick arrays. Without any correction, 4.1% FWHM energy resolution was measured from one pixel of 3x3 array at 662 keV at room temperature. To minimize the polarization effect, lowering the operation temperature was applied to 13 mm thick array and the stable operation beyond 8 months could be seen without any significant degradation of detector performance. Much improved energy resolution of 2.2% or less at 662 keV has been also obtained from one pixel with depth correction. In this paper improved charge collection with Cr contacts and our recent progress made in long term stability of TlBr detectors at room temperature by applying post annealing are presented. [ABSTRACT FROM PUBLISHER]

In recent years, progress in processing and crystal growth methods have led to a significant increase in the mobility-lifetime product of electrons in thallium bromide (TlBr). This has enabled single carrier collection devices with thickness greater than 1-cm to be fabricated. In this paper we report on our latest results from pixellated devices with depth correction as well as our initial results with Frisch collar devices. After applying depth corrections, energy resolution of approximately 2% (FWHM at 662 keV) was obtained from a 13-mm thick TlBr array operated at -18^\circC and under continuous bias and irradiation for more than one month. Energy resolution of 2.4% was obtained at room temperature with an 8.4-mm thick TlBr Frisch collar device. [ABSTRACT FROM PUBLISHER]

Thallium bromide (TIBr) is a dense, high-Z, wide bandgap semiconductor that has potential as an efficient, compact, room temperature nuclear radiation detector. In this paper we report on our recent progress in TIBr nuclear detector development. In particular, improvements in material purification have led to an order of magnitude increase in the mobility-lifetime product of electrons, (μτ)e, to as high as 5 ×10-3 cm²/V. This has enabled much thicker detectors with good charge collection to be fabricated. We fabricated and tested small pixel TlBr arrays up to 10mm thick. The energy resolution ∼ 2% FWHM at 662 keV was recorded with 5-10 mm thick devices without 3-D spectral cor- rection. We also investigated the long-term detector stability and were able to constantly operate a thin (0.5 mm) detector for five months at - 18°C, under an electric field and with irradiation. [ABSTRACT FROM AUTHOR]