Transactions on Electrical and Electronic Materials

The Korean Institute of Electrical and Electronic Material Engineers (한국전기전자재료학회)
권호 표지
DOI QR코드

DOI QR Code

A Polycrystalline CdZnTe Film and Its X-ray Response Characteristics for Digital Radiography

  • Published : 2003.10.01
Download PDF
⟨ Previous Next ⟩

Abstract

The Cd$\_$1-x/Zn$\_$x/Te film was produced by thermal evaporation for the flat-panel X-ray detector. The crystal structure and the surface morphology of poly crystalline Cd$\_$1-x/Zn$\_$x/Te film were examined using XRD and SEM, respectively. The leakage current and X-ray sensitivity of the fabricated films were measured to analyze the X-ray response characteristic of Zn in a polycrystalline CdZnTe thin film. The leakage current and the output charge density of Cd$\_$0.7/Zn$\_$0.3/Te thin film were measured to 0.3 1nA/$\textrm{cm}^2$ and 260 pC/$\textrm{cm}^2$ at an applied voltage of 2.5 V/$\mu\textrm{m}$, respectively. Experimental results showed that the increase of Zn doping rates in Cd$\_$1-x/Zn$\_$x/Te detectors reduced the leakage current and improved the X-ray sensitivity significantly. The leakage current was drastically diminished by the formation of thin parylene layer in the Cd$\_$0.7/Zn$\_$0.3/Te detector.

Keywords

References

  1. S. Vedantham, G. C. Giakos, A. Dasgupta, B. Pillai, S. Chowdhury, and P. Ghotra, 'Electrical characterization of CdZnTe imaging detectors for digital radiography', SPIE, Vol. 3032, p. 499, 1997 https://doi.org/10.1117/12.274021
  2. A. A. Melnikov, 'CdZnTe radiation detectors', J. of Crystal Growth, Vol. 197, p. 663, 1999 https://doi.org/10.1016/S0022-0248(98)00967-1
  3. W. Que and J. A. Rowlands. 'X-ray imaging using amorphous selenium: inherent spatial resolution', Med. Phys., Vol. 22, No. 4, p. 365, 1995 https://doi.org/10.1118/1.597471
  4. S. Tokuda, S. Adachi, T. Sato, T. Yoshimura, H. Nagata, K. Uehara, Y Izumi, O. Teranuma, and S. Yamada, 'Experimental evaluation of a novel CdZnTe flat panel X-ray detector for digital radiography and fluoroscopy', Proc. SPIE, Vol. 4320, p. 140, 2001 https://doi.org/10.1117/12.430924
  5. J. K. Park, S. S. Kang, J. H. Kim, C. W. Mun, and S. H. Nam, 'Zinc sulfide selenium x-ray detector for digital radiography, Trans. EEM, Vol. 3(4), p. 16, 2002
  6. H. Hermon, M. Schieber, A. Zuck, A. Vilensky, L Melekhov, E. Shtekel, A. Green, O. Dagan, S. E. Ready, R. A. Street, E. S. Seppi, R. Pavlyuchkova, G. VirshuP, G. Zentai, and L. Partain, 'Deposition of thick films of polycrystalline mercuric iodide x-ray detectors', SPIE, Vol. 4320, p. 133, 2001 https://doi.org/10.1117/12.430922
  7. G. C. Giakos, S. Vedantham, S. Suryanarayanan, S. Chowdhury, R. Guntupalli, J. Odogba, V. VegaLozada, B. Pillai, and D.B. Sheffer, 'Image analysis of CdZnTe detectors for digital radiography', IEEE Instrumental and Measurement Technology Conference, p. 358, 1998
  8. L. Verger, J. P. Bonnefoy, F. Glasser, and P. Overier Buffet, 'New developments in CdTe and CdZnTe detectors for x and $\gamma -ray applications', J. Electronic Materials, Vol. 26, No. 6, p. 738, 1997 https://doi.org/10.1007/s11664-997-0225-2
  9. A. Jahnke and R. Matz, 'Signal formation and decay in CdTe x-ray detectors under intense irradiation', Med. Phys., Vol. 26, No. 1, p. 38, 1999 https://doi.org/10.1118/1.598475
  10. J. C. Erickson, H. W. Yao, R. B. James, H. Hermon, and M. Greaves, 'Time of flight experimental studies of CdZnTe radiation detectors', J. of Electronic Materials, Vol. 29, No. 6, p. 699, 2000 https://doi.org/10.1007/s11664-000-0208-z
  11. S. S. Kang, J. H. Kim, H. W. Lee, C. W. Mun, and S. H. Nam, 'X-ray response characteristic of Zn in the polycrystalline $Cd_{1-x}Zn_{x}Te$ detector for digital radiography', Trans. EEM, Vol. 3(2), p. 28, 2002
  12. A. Cavallini, B. Fraboni, W. Dusi, M. Zanarini, and P. Siffert, 'Deep levels and compensation in $\gamma$ -irradiated CdZnTe', Appl. Phys. Lett., Vol. 77, No. 20, p. 3212, 2000 https://doi.org/10.1063/1.1324980