The Study Of The Preparation And Physical Properties Of CdZnTe Polycrystalline And Amorphous Films

Cd1-xZnxTe crystal (CZT) gets widespread attention, because of its excellent optical performance. Currently, it is considered as one of the best material for making room temperture nuclear radiation detectors, with its high resistivity, larger and adjustable band gap, excellent carrier transport performance, relatively low leakage current character and so on. The CdZnTe crystals used in a wide range of detection is limited, because high-quality and large-size CdZnTe single crystal growth is difficult and costly. However, CdZnTe film has become a hot topic with its low consumable cost savings and easy to large area deposition. In this paper,CdZnTe thin films and amorphous films were deposited by RF magnetron sputtering with Cd0.9Zn0.1 Te crystal as the target, and a comparative study was made.The CdZnTe thick films were prepared by cyclic batch sputtering and studied the detection effect simplely.In this paper, CdZnTe polycrystalline films were prepared by magnetron based on physical vapor deposition. First, the influence of magnetron preparing process parameters on the structure and properties of CZT crystalline film has studied. Second, amorphous film was prepared by providing a little nitrogen into sputtering process, and the CdZnTe polycrystalline films and amorphous films were compared. All films were investigated by means of X ray diffraction, atomic force microscopy, electron probe, UV-VIS spectrophotometer and semiconductor tester. The results show that: in order to obtain a better structure and performance of CdZnTe thin films, the sputtering power is 80W, the argon pressure is 2.5Pa, the sputtering time is 2h, the target spacing is 6.5cm. At this time the resistivity reaches 109 orders of magnitude. The polycrystalline and amorphous CdZnTe films prepared under the same conditions were compared, which shows that the band gap of amorphous films is larger, and the resistivity is 103 orders of magnitude higher than that of polycrystalline ones.In order to meet the detection requirements of the film detector, multiple sputtering is needed to increase the thickness of the film. In this paper, the thickness of 20?m CdZnTe thick film was prepared by the method of the 8 sputtering, and the structure and the detection effect were studied. The thickness of 20?m CdZnTe film has been prepared by 8 sputtering, and the structural properties and the detection effect are studied.