Nature of Growth Pits in Lead Salt Epilayers Grown by Molecular Beam Epitaxy

摘要

We present a detailed study on the surface morphologies and chemical composition of growth pits in lead selenide (PbSe) epilayers grown by molecular-beam epitaxy. Various growth pits were investigated by scanning electron microscopy and energy-dispersive x-ray analysis. The vast majority of growth pits within the PbSe epilayers contained either single or multiple PbSe microcrystals with a distinct cuboid shape. Based on the observed structures and morphologies of the PbSe microcrystals, the formation mechanism of the cuboid structures was considered to be (100) preferential crystal growth originating from PbSe polycrystalline seeds.