Photoluminescence study in step-graded composition In xAl 1- xAs/GaAs
Abstract
We report on the lattice-mismatched growth of step-graded In xAl 1- xAs buffer layers on GaAs (0 0 1) substrates by molecular beam epitay (MBE). The approach to growing highly lattice-mismatched epilayers is to interpose a buffer layer between the substrate and the active layer. Two samples G30 and G40 with active layer compositions, respectively, x = 0.46 and x = 0.41, are studied by photoluminescence (PL). At low temperature, the PL spectra show a large broadened band whose energy and intensity depend on the active layer composition. The step-graded layer compositions improved the crystalline quality of these structures and increase the active layer PL band intensity.
- Publication:
-
Applied Surface Science
- Pub Date:
- October 2006
- DOI:
- 10.1016/j.apsusc.2006.05.095
- Bibcode:
- 2006ApSS..253..292Y