ARI-SA: Infrared Studies of CdMgTe as the Material of Choice for Room Temperature Gamma-Ray Detectors

0736133 .为了保护我国免受核恐怖主义的威胁，迫切需要快速检测和鉴定核同位素的能力。来自纽约城市学院、光学半导体公司和布鲁克海文国家实验室的一个研究小组将在光谱表征、材料生长和设备制造/测试方面共同努力，以改进CdMgTe作为室温伽马射线探测器的首选材料。基于cdte的探测器在室温下具有高效率和高光谱分辨率的潜力。锗或硅探测器需要低温才能工作，其停止功率较低。碘化汞探测器具有很高的阻止能力，但存在许多机械和生长问题。碲化镉锌（CZT）近年来受到重视，但产量低，生长速度慢。相比之下，碲化镉（CMT）具有许多优点：(i)它具有更小的合金晶格错配，因此具有更好的机械性能；（ii）具有较高的带隙，因此在环境温度下具有较高的电阻率；（iii）它应该导致更容易制造p-i-n器件结构。

0736133TuThe capability of rapid detection and identification of nuclear isotopes is urgently needed to protect our nation from nuclear terrorism. A research team from the City College of New York, Optical Semiconductors, Inc. and Brookhaven National Laboratories will combine efforts in spectroscopic characterization, material growth, and device manufacturing/testing to improve CdMgTe as the material of choice for room temperature gamma-ray detectors. CdTe-based detectors have the potential of high efficiency and high spectral resolution at room temperature. Ge or Si detectors need cryogenic temperatures for operation and their stopping power is low. Mercury iodide detectors have high stopping power, but have many mechanical, and growth problems. Cadmium zinc telluride (CZT) has recently become prominent, but it has low yield and slow growth rate. Cadmium magnedium telluride (CMT) has many advantages in comparison: (i) it has a much smaller lattice mismatch for alloying and therefore better mechanical properties; (ii) it has higher bandgap and hence high resistivity at ambient temperature; (iii) it should lead to easier fabrication of p-i-n device structure.