THERMAL STABILITY OF Hg1 - xCdxTe CRYSTALS COVERED WITH THE ANODIC OXIDE FILMS.

Hg loss from the near-surface region of Hg//1// minus //xCd//xTe with and without anodic oxide caps by a 60-min heat-treatment has been estimated for x approximately equals 0. 2 and x approximately equals 0. 3 from 40-Mev-O**5**30 backscattering spectra. The Hg loss rate for various heat-treatment temperatures T was compared with the T-dependence of the Hg content of the oxide films. For x approximately equals 0. 2, the Hg loss of a sample with 1000 A oxide film exceeded 1 multiplied by 10**1**7 Hg/cm**2 at T greater than 300 degree C, while that of the uncapped sample reached the same level around T equals 250 degree C. For x approximately equals 0. 3, the Hg loss was not appreciable up to 320 degree C, even for an uncapped sample; however, it exceeded 1 multiplied by 10 **1**7 Hg/cm**2 around T equals 340 degree C, even for a capped sample. Furthermore, the Hg content of anodic oxide films rapidly decreased in the temperature range 250-290 degree C for both x approximately equals 0. 2 and x approximately equals 0. 3. These behaviors suggest that protective effect of the oxide cap against Hg loss decreases with decreasing Hg-content of the films.