Control of epitaxial layers grown on 4H–SiC: from 3C microcrystalline inclusions to type II quantum well structures

Abstract

Listen

Translate article

AbstractWe report the results of a series of LTPL (Low Temperature PhotoLuminescence) investigation performed on n‐type, non‐intentionally doped, 4H–SiC samples. We focus on the defect structure introduced by a growth fault in the stacking sequence. We treat the fault as a 3C quantum well embedded in a 4H–SiC matrix and use a simple 2‐dimensional approximation to deduce the extent of the lattice perturbation associated with a given defect. We show that the intrinsic type‐II nature of the band alignment, combined with the effect of the spontaneous polarization, must result in a double bound‐exciton signature per well, which is resolved for the first time. The comparison with experimental results confirms also that, after a relatively small critical layer thickness, the back conversion from cubic to hexagonal remains an unsolved problem. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)