Ion channeling analysis of GaAs/sub x/P/sub 1-x/GaP strained-layer superlattices
Abstract
Axial ion channeling and backscattering with 2 MeV (4)He are used to probe the strain in GaAs 16P 84/GaP strained-layer superlattices (SLS) by two methods. The tetragonal distortions in the growth direction of SLS's give rise to alternating tilts in inclined crystal directions at each interface. In the first method the large increase in dechanneling along 110 directions containing the angular tilts is measured relative to the negligible increase in dechanneling along the 100 growth direction. This method provides a sensitive depth-dependent measure of strain but requires computer simulation for quantitative analysis. In the second method, channeling angular scans are used to directly measure the lattice strain by the shift in the 110 crystal direction in the top layer relative to the average 110 direction. These results demonstrate the validity of the strain accommodation model for the interpretation of the dechanneling and indicate that GaAs/sub x/P/sub 1-x//GAP SLS structures of high crystalline quality can be obtained with strain somewhat lower than that predicted theoretically from bulk lattice properties.
- Publication:
-
Presented at the Mater. Res. Soc. Ann. Meeting
- Pub Date:
- November 1983
- Bibcode:
- 1983mrs..meetQ....P
- Keywords:
-
- Backscattering;
- Crystal Lattices;
- Gallium Arsenides;
- Gallium Phosphides;
- Ion Beams;
- Alpha Particles;
- Chemical Composition;
- Computerized Simulation;
- Prediction Analysis Techniques;
- Spectrum Analysis;
- Strain Gages;
- Solid-State Physics