ZnSTe coherently grown onto GaP substrates by molecular beam epitaxy using ZnS buffer layers

ZnS1-xTex epitaxial layers with x ~ 0.06, nearly lattice-matched to GaP substrates, have been grown by molecular beam epitaxy. Direct growth of the layers onto the substrates results in poor crystal quality, showing no sign of coherent growth. This seems to be due to alloy composition deviation at the initial stage of the growth. To avoid the problem, a thin coherent ZnS buffer layer has been inserted at the ZnSTe/GaP interface. With the buffer layers, coherent growth of ZnSTe layers is achieved and the crystal quality has been improved.