缺陷抗矿化合物Hg3Q2I2 (Q=S,Se和Te) 用于室温硬辐射检测
Yihui He1, Oleg Y Kontsevoi1, Constantinos C Stoumpos1
1Department of Chemistry, ‡Department of Materials Science and Engineering, §Department of Electrical Engineering and Computer Science, and ∥Department of Physics and Astronomy, Northwestern University , Evanston, Illinois 60208, United States.
Journal of the American Chemical Society
|May 16, 2017
概括
像Hg3Se2I2这样的高Z合物显示为室温半导体探测器的X射线和马射线. Hg3Se2I2具有优异的性能,可以实现对α粒子和马射线的光谱分辨率.
科学领域:
- 材料科学
- 固态物理
- 探测器物理
背景情况:
- 高Z合物,特别是Hg3Q2I2 (Q=S,Se,Te),是有序空缺的缺陷抗氧化物.
- 这些材料被研究为X射线和马射线应用的潜在半导体探测器.
研究的目的:
- 探索Hg3Q2I2化合物的结构变化和由此产生的特性.
- 评估它们适用于室温辐射检测.
- 确定该类中用于探测器应用最有前途的材料.
主要方法:
- 使用蒸汽运输方法合成大型单晶体.
- 光学,电气和机械性能的表征.
- 使用各种辐射源 (例如241Am,57Co) 的薄Hg3Q2I2晶体制造和测试探测器.
主要成果:
- 所有Hg3Q2I2化合物都具有高密度 (> 7 g/cm3),宽带间 (> 1.9 eV) 和高电阻率 (> 10^11 Ω cm).
- Hg3Se2I2具有近乎一维的结构,具有更分散的导电带和较低的电子有效质量 (0.20 m0).
- Hg3Se2I2探测器实现了5.49 MeV的α粒子 (19%的FWHM) 和59.5 keV的马射线 (50%的FWHM) 的光谱分辨率.
- 载体移动性-生命周期乘积 (μτ) 达到10^-510^-6cm^2/V,电子移动性在Hg3Se2I2估计为104±12cm^2/V·s.
结论:
- Hg-Q图案的尺寸性对电子带结构和探测器性能有很大的影响.
- 在研究的化合物中,Hg3Se2I2表现出卓越的性能,使其在室温辐射检测方面非常有前途.
- 这些材料为敏感且强大的辐射检测提供了可行的替代方案.
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