HgCdTe Surface Study Program
Abstract
This report presents the conclusions of a two-year study of the surface of HgCdTe conducted jointly by Santa Barbara Research Center and Stanford University. Photoemission spectroscopy (PES) of HgCdTe cleaved in UHV has indicated a surface which is very stable against Hg loss. The surface has shown a tendency to type-convert (p to n) due to defects in the surface region stressed by cleaving. Type conversion has been confirmed by independent electrolytic electro-reflectance (EER) measurements. Photoemission has also been used to probe the bulk band structure and indicates a fundamental difference in bonding of Cd and Hg in the lattice. A breakdown of the virtual crystal approximation is noted and an improved computation for the alloy is discussed. Oxygen chemistry has been studied using PES; results show the undamaged surface is inert to unexcited molecular oxygen. Oxidation proceeds with exposure to excited oxygen and is preceded by a loss of Hg from the surface. The oxide formed does not contain Hg. Differences in oxidation between HgTe and HgCdTe indicate Cd plays a role in the oxidation.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1982
- Accession Number
- ADA132071
Entities
People
- Jerry A. Wilson
- Joel Silberman
- Per Morgen
- W. E. Spicer