Surface phase transition and interface interaction in the α-Sn/InSb{111} system

Abstract

Thin films of \ensuremath{\alpha}-Sn were epitaxially grown on InSb(111)A and InSb(111)B substrates at room temperature. We studied growth modes and phase transitions of the films by using reflection high-energy electron diffraction and Auger electron spectroscopy. The films on InSb(111)A grew in biatomic layer-by-layer modes. Characteristic growth features for Sn/InSb(111)B were due to the segregation of Sb to the \ensuremath{\alpha}-Sn film surface. Thus, we used the Sn/InSb(111)A system to examine the stability of the films as a function of Sn coverage. The as-grown film surfaces changed irreversibly from the (3\ifmmode\times\else\texttimes\fi{}3) structure, to the (2\ifmmode\times\else\texttimes\fi{}2), and, subsequently, to the (1\ifmmode\times\else\texttimes\fi{}1) structure, and finally to melting while going to elevated temperatures. The transition temperatures for the thinner film were more than 10 \ifmmode^\circ\else\textdegree\fi{}C higher than for the thicker film. Finally, to study the role of an interface in the stable growth of \ensuremath{\alpha}-Sn on InSb(111)A, we performed discrete variational X\ensuremath{\alpha} cluster calculations.