Investigation of Impurity Redistribution Effects and Solubility/Diffusivity of Cr IN GaAs.
Abstract
Experiments have begun on the investigation of the thermodynamics and phase equilibrium of the Ga-Cr-As system and the solubility and diffusivity of Cr in GaAs under selected conditions of temperature and source composition. Allied experiments on the influence of defects in GaAs have shown the stable front surface of Cr depletion channels can be formed in GaAs for retarding the outdiffusion of Cr. Investigations of the influence of non-stoichiometric regions introduced by implantation ( as predicted by the Christel-Gibbons model) on the redistribution of Cr after annealing have shown a definitive correlation between predicted damage zones and experimentally observed gettering regions. The field-enhanced diffusion of Cr into contact regions of GaAs-FETs under thermal-bias stress testing has now been shown to be correlated with the degradation of contacts during stress. Separate experiments of CZ-Si (containing oxygen) have shown that oxygen is extremely mobile in back surface damaged regions and ion implanted junctions of Si wafers. Motion and gettering of 160 into processing regions has been demonstrated at annealing temperatures as low as 350 deg. Evaluations of CdTe, HgCdTe and LPE-HgCdTe/CdTe samples currently used in IR detector fabrication have shown extreme variability in the concentrations of defects, precipitation and propagation of defects into active device regions. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1981
- Accession Number
- ADA104180
Entities
People
- Calvin Leung
- D. Stevenson
- R. A. Armistead
- R. Ormond
- T. J. Magee