High temperature arsenic doping of CdHgTe epitaxial layers

Abstract

Experimental results on solid-state arsenic doping of the n-type bulk and ISOVPE epitaxial Cd X Hg 1-X Te (X = 0.19÷0.3) alloys are presented. The arsenic doped thin epitaxial Cd x Hg 1-x Te films (n As ≈ 5⋅10 16 ÷1⋅1020 cm -3; d =2÷5 µm) obtained by RF sputtering in a mercury glow discharge were used as As diffusion sources. The arsenic diffusion and activation were carried out at temperatures Т = 500÷600°С under Hg vapour pressure. Immediately after the high temperature treatment all samples were annealed to annihilate point defects. The SIMS analysis was used for determination of the quantitative admixture distribution of As in the diffusion area. The arsenic electrical activity has been evaluated by means of differential Hall, resistivity and thermoemf measurements. The analysis of experimental data obtained as well as their comparison with previously obtained results has been performed.

Barrier Structures on the Basis of Graded-Band-Gap CdHgTe Obtained by Evaporation-Condensation-Diffusion Method

“…Cooling of ampoules after annealing was carried out directly in the oven after switching them off. The developed technique of multistage thermal annealing of epitaxial layers and structures based on Сd X Hg 1-X in vapor of solid solution components for the temperatures in range T = 150 -600°C [18,19] ensured the preservation of the crystal structure of near-surface regions of experimental samples [20] and allowed us to use them to create photovoltaic structures [21].…”