Lateral Composition Modulation in AlAs/InAs Short Period Superlattices Grown on InP(001)
Spontaneous lateral composition modulation as a consequence of the deposition of a (A1As)n/(InAs)m short period superlattice on an InP(001) substrate is examined. Transmission electron microscopy images show distinct composition modulation appearing as vertical regions of In- and Al-rich materials alternating in the [110] projection. Ther periodicity of the modulation is 130.ANG., and is asymmetric. The transmission electron and x-ray diffraction patterns from the structure exhibit distinct satellite spots which correspond ot the lateral periodicity. Transmission electron microscopy images show that the individual superlattice layers possess cusplike undulations, which directly correlate with the composition modulation. Composition modulation in this sample appears to be coupled to morphological and compositional instabilities at the surface due to strain.
- Research Organization:
- National Renewable Energy Laboratory (NREL), Golden, CO.
- Sponsoring Organization:
- USDOE
- DOE Contract Number:
- AC36-99GO10337
- OSTI ID:
- 915628
- Journal Information:
- Applied Physics Letters, Journal Name: Applied Physics Letters Journal Issue: 11, 17 March 1997 Vol. 70; ISSN APPLAB; ISSN 0003-6951
- Country of Publication:
- United States
- Language:
- English
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