AlSb compositional nonuniformity induced by different Ga-Al exchange modesin the melt growth of AlxGa1-xSb

Citation
Wd. Huang et al., AlSb compositional nonuniformity induced by different Ga-Al exchange modesin the melt growth of AlxGa1-xSb, JPN J A P 1, 40(7), 2001, pp. 4648-4651
Citations number
13
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science
Volume
40
Issue
7
Year of publication
2001
Pages
4648 - 4651
Database
ISI
SICI code
Abstract
The AlSb compositional nonuniformity in a melt grown AlxGa1-xSb crystal aro und the macrostep and the boundary between the facet and off-facet was meas ured using a spatially resolved photoluminescence (SRPL) technique. It was found that the AlSb composition is higher in the riser part of a macrostep than in the terrace part. It was also found that in the riser part the AlSb composition increases continuously as the step density increases. In the f acet/off-facet transition region, it is shown that the AlSb composition in the off-facet area is 13% higher than in the facet area. The experimental r esult is explained qualitatively by assuming that the AlSb compositional no nuniformity is induced by different degrees of Ga-Al exchange, which depend s on the step velocity. It is concluded that even at temperatures as high a s the melting point, the Ga-Al exchange cannot reach an equilibrium and the incorporation of Al depends on the degree of misorientation.