MBE growth and properties of SiC multi-quantum well structures

Multi-quantum well structures with 3C-SiC wells between alpha -SiC barriers were grown in a two-step procedure by solid-source molecular beam epitaxy. First, one-dimensional wire-like 3C-SiC was nucleated selectively on terraces of the well-prepared off axis alpha -SiC(0 0 0 1) substrates at low temperature (T < 1500 K). Next, 3C-SiC lamellae were incorporated into the hexagonal layer material via simultaneous step-flow growth mode of both the 3C-SiC nuclei and the hexagonal substrate material at higher T and Si-rich conditions. In comparison to homopolytypic SiC layers, photoluminescence investigations revealed additional signals, which can be explained by optical transitions within the thin cubic well layers. (C) 2001 Elsevier Science B.V. All rights reserved.