Use of spectrally resolved scanning photoluminescence for optimizing the growth conditions of InAlAs/InP heterostructures

Optimum growth conditions were determined for InAlAs/InP heterostructure materials based on scanning photoluminescence (SPL), structural and electrical characteristics of wafers. The impact of MOCVD growth parameters such as susceptor rotating speed on compositional and thickness uniformity of the layer is also reported using SPL. SPL and complementary thickness measurements showed the correlation between compositional and thickness uniformity and suggest that the spatial uniformity of the boundary layer is responsible for the spatial uniformity of the grown layers. Thus, the use of non-destructive techniques such as SPL is very useful for optimizing growth parameters. Compositional uniformity as determined by SPL could, for example, be a measure for speed, temperature and boundary layer optimization. Our results show that for the MOCVD reactor geometry and growth conditions used, a low rotating speed of 100 rpm appears to be the optimum for better composition and thickness spatial uniformity.