Recent results from pixelated TlBr detectors with Tl electrodes operated at room-temperature
Recent results from pixelated TlBr detectors with Tl electrodes operated at room-temperature
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具有室温操作 Tl 电极的像素化 TlBr 探测器的最新结果
DOI：
10.1109/nssmic.2016.8069952
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发表时间：
2017
期刊：
影响因子：
--
通讯作者：
K. Hitomi
中科院分区：
文献类型：
--
作者：
C. Leak;W. Koehler;S. O'Neal;Z. He;K. Hitomi
溴化铊（TlBr）具有高原子序数、高密度和宽带隙等优点，是一种可行的室温伽马能谱替代材料。在5mm厚的像素化器件上，已经实现了662 keV下低于1%的FWHM能量分辨率，然而，这些结果大多局限于在-20°C下的稳定运行。在室温下工作时，器件会退化并失效，这种现象被称为极化。极化可能是由离子传导促进的体与接触相互作用引起的。2008年，Hitomi等人发现使用Tl电极可以延长室温寿命。在这项工作中，我们验证了带有Tl电极的4.1 mm厚像素化TlBr探测器的稳定室温性能。能量分辨率、迁移寿命乘积和电阻率进行了表征。所有深度和阴极侧事件的分辨率分别为1.6%和1.2% FWHM。计算出一个非常高的电子迁移率寿命产品：3.1±0.2·10-2 cm2/V。
Thallium-bromide (TlBr) is a viable alternative to CZT for room-temperature gamma ray spectroscopy because of its high atomic number, high density, and wide band-gap. Sub-1% FWHM energy resolution at 662 keV has been achieved on 5 mm thick pixelated devices, however, these results are mostly limited to stable operation at -20°C. During room-temperature operation, the devices degrade and fail, a phenomenon known as polarization. Polarization is likely caused by bulk-to-contact interactions facilitated by ionic conduction. In 2008, Hitomi et al. found that room-temperature lifetime could be extended by applying Tl electrodes. In this work we verify stable room-temperature performance of a 4.1 mm thick pixelated TlBr detector with Tl electrodes. Energy resolution, mobility-lifetime product, and resistivity are characterized and presented. Resolutions of 1.6% and 1.2% FWHM are achieved for all depths and cathode-side events only, respectively. A very high electron mobility-lifetime product is calculated: 3.1±0.2 ·10-2 cm2/V.