an epitaxial film of a iii - v compound may be formed on a non - native substrate by sequentially forming a plurality of epitaxial layers on the substrate at a growth temperature . by cooling the substrate and each sequentially grown epitaxial layer to a sub - growth temperature prior to resumption of epitaxial growth , stress within the sample is periodically relieved . sequential epitaxial growth is combined with system etching to provide an epitaxial layer which not only has a lower propensity to shatter , but also exhibits improved surface morphology . sequential hydride vapor - phase epitaxy using hcl as both source gas and etchant , allows integration of sequential deposition and system etching into a single process .