Dielectric and pyroelectric properties of ordered CdZnTe layers grown by MOCVD

Cd1-xZnxTe (0.1 less than or equal to x less than or equal to 0.86) layers were epitaxially deposited on (100) CdTe and on Cd0.96Zn0.04Te substrates by MOCVD, and some of their electrical and optical properties were investigated. The dielectric constant as a function of temperature was found to have a peak at a Curie temperature. At this same temperature the slope of the resistivity showed a sharp change. It was found that the layers were pyroelectric. The pyroelectric coefficient varied from 2.3 x 10(-11) to 5.1 x 10(-10) C K-1 m(-2), depending on Zn content (x) and growth conditions. It was observed that the Curie temperature shifts in the direction of higher temperatures when the Zn content of the layers increases. The observed results are consistent with the results obtained on CdZnTe monocrystals. A correlation was observed between the pyroelectric properties of CdZnTe and valence band splitting effect, measured by the photoluminescence method at 77 K. (C) 1999 Elsevier Science B.V. All rights reserved. PACS: 77.80.Bh; 73.61.Ga; 77.70. + a; 78.30. - j; 78.66.Hf.