Low-Energy Electron Diffraction Study of the Surface-Defect Structure of Ge Grown Epitaxially on GaAs (110).
Abstract
This abstract summarizes initial results of an investigation of the surface defects in Ge films grown epitaxially on cleaved GaAs(110). Most of the effort has centered on characterizing the electronic properties of the interface, i.e., band gap discontinuities, localized bonding, work function changes, and abruptness of the interface. X-ray and ultraviolet photoelectron spectroscopy have been used as the main analytical techniques in these investigations. In summary, we have demonstrated that it is possible to extract quantitative information on structural defects even for (1x1) overlayers using LEED. For epitaxial growth of Ge on GaAs(110) under the present experimental conditions, the overlayers appear to have a higher concentration of extended defects than the substrates on which they are grown. At low growth temperatures, this may be due to a mechanism that inhibits layer-by-layer growth, causing the surface to be highly stepped. For annealed layers, dislocations grown into the film may propagate to the surface and cause the Ge layer to be polycrystalline but sill oriented. The symmetry of the patterns differs from that observed by Moench and Gant. It is possible that the appearance of superlattices is related to growth mode.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 10, 1981
- Accession Number
- ADA097599
Entities
People
- D. G. Welkie
- H. M. Clearfield
- M. G. Lagally
Organizations
- University of Wisconsin–Madison