Epitaxial growth of lattice mismatched SrF₂ films on (100) GaAs

Abstract

For the first time insulating epitaxial SrF₂ films on (100) GaAs substrates have been grown by thermal deposition followed by in situ annealing process. Structural properties of SrF₂ films examined by X-ray diffraction, scanning electron microscopy and transmission electron microscopy indicate a very good crystalline quality. It is observed from the X-ray analysis that SrF₂ layers thinner than 100 nm suffer two dimensional compressive stress due to the lattice misfit while those thicker than 100 nm suffer two dimensional tensile stress due to the difference in the thermal expansion coefficients.