Surface Contrast in Two Dimensionally Nucleated Misfit Dislocations in InAs<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mo>/</mml:mo></mml:math>GaAs(110) Heteroepitaxy

Abstract

Scanning tunneling microscopy has been used to study misfit-dislocation (MD) induced lattice distortion of the epilayer for InAs thin films grown on GaAs(110). Two-dimensional (2D) islands with regular size are observed in the first two monolayers. Interfacial MDs, identified in the images by an array of dark lines, appear following the coalescence of the 2D islands. The growth mode remains 2D for all coverages and the vertical contrast of these lines decreases with film thickness. The surface contrast can be explained only by classical elasticity theory if the properties of a thin InAs film with an exposed surface are considered.