EFFECT OF METAL CONTACT ON THE CZT DETECTOR PERFORMANCE

  • Published : 2009.06.30

Abstract

Metal-semiconductor contact is very important for the operating property of semiconductor detector. $Cd_{0.96}$ $Zn_{0.04}$ Te semiconductor crystal was grown with Bridgman method, and the crystal was cut and polished. EPMA (Electron Probe Micro Analyzer) and ICP-MS (Inductively Coupled Plasma Mass Spectrometry) analysis were done to obtain the chemical composition and impurity of the crystal. Metal contact was deposited with thermal evaporator on both sides of the crystal. Detectors with Au/CZT/Au and In/CZT/Au structure were made, and I-V curve and the energy spectrum were measured with the detectors. It could be seen that the detector with the In/CZT/Au structure has superior property than the detector with Au/CZT/Au structure when the crystal resistivity was low. However, the metal contact structure effect becomes low when the crystal resistivity was high.

Keywords

References

  1. Schlesinger TE, Toney JE, Yoon H, Lee EY, Brunett BA, Franks L, James RB. Cadmium zinc telluride and its use as a nuclear radiation detector material. Materials Science and Engineering 2001;32:103-189 https://doi.org/10.1016/S0927-796X(01)00027-4
  2. Szeles C, Cameron SE, Ndap JO, Reed MD. Advances in the high-pressure crystal growth technology of semi-insulating CdZnTe for radiation detector applications. Proc. SPIE 2004;5198:191–195 https://doi.org/10.1117/12.514618
  3. Kim HS, Park SH, Kim YK, Ha JH, Kang SM, Cho SY. Correlation between the surface roughness and the leakage current of an SSB radiation detector. Nucl. Instr. Meth. A 2007;579:117–119 https://doi.org/10.1016/j.nima.2007.04.021
  4. Ozsan ME, Hossain EJ, Hossain MA. CdZnTe Schottky diodes for radiation spectroscopy. Nucl. Sci. Sym. 2001;4:2276–2280 https://doi.org/10.1109/NSSMIC.2001.1009277
  5. http://www.evproducts.com