Article contents
Defects in Large-Misfit Heteroepitaxy
Published online by Cambridge University Press: 28 February 2011
Abstract
A Transmission Electron Microscopy (TEM) study is presented of GaAs on Si (100) and CdTe on GaAs (100), and the implications for defect nucleation mechanisms are discussed. MOCVD GaAs/Si is shown to grow by island nucleation followed by 3D growth. Single islands are free of inversion domain boundaries (or “APBs”) implying that a single domain is able to grow over a demi-step on the substrate surface during this 3D growth. Misfit dislocations are shown to be edge type during island growth, with 60° type being generated at island junctions. The predominant threading dislocations are found to have inclined a/2 <110> Burgers vectors. The implied mechanisms for the generation of both misfit and threading dislocations are discussed. In MOCVD CdTe/GaAs the microstructure is shown to have a number of qualitatively similar features; in addition, study of this much larger misfit system allows us to deduce a possible explanation for misorientation effects in these systems.
- Type
- Research Article
- Information
- Copyright
- Copyright © Materials Research Society 1988
References
- 8
- Cited by