Growth of Thick Epitaxial CdTe Films by Close Space Sublimation
- 275 Downloads
This paper reports on a detailed study of the development of the close space sublimation method, which has been widely used in the preparation of polycrystalline CdTe/CdS solar cells, as an epitaxial method for the growth of thick CdTe single crystal films over 200 μm on GaAs and Ge substrates for high-energy radiation detectors. The resulting microscopic growth phenomena in the process are also discussed in this paper. High-quality single crystalline CdTe thick films were prepared with x-ray rocking curves full width at half maximum (FWHM) values, which were ∼100 arcsec on Ge substrates and 300 arcsec on GaAs substrates. The quality of thick films on Ge(100) showed a substantial improvement with nucleation in a Te-rich growth environment. No Te inclusions in the CdTe films grown on GaAs(211)B and Ge(100) were observed with IR transmission imaging. Photoluminescence of CdTe/Ge shows a large reduction in the 1.44 eV defect energy bands compared with films grown on GaAs substrates. The film resistivity is on the order of 1010 Ω cm, and the film displayed some sensitivity to alpha particles.
Key wordsCdTe detector epitaxy thick film
Unable to display preview. Download preview PDF.
- 9.J.P. Faurie, R. Sporken, Y.P. Chen, M.D. Lange, and S. Sivananthan, Mater. Sci. Eng. B Solid State Mater. Adv. Technol. 16, 51 (1993).Google Scholar
- 12.E. Bolotnikov, S. Awadalla, S. Babalolal, G.S. Camarda, H.␣Chen, Y. Cui, A. Hossain, H. Jackson, J. James, J. MacKenzie, G. Yang, and R.B. James (2008) Studies of the Extended Defects in CdZnTe Radiation Detectors. IEEE Room Temperature Semiconductor Detector Workshop, Dresden, 19–25 October.Google Scholar