Initial Stages of Interface Formation in the Si/Sn System

Group IV-IV heterostructures with Sn as one constituent have potentially important applications We report on an investigation of the initial stages of interface formation for deposition of Sn on Si(100)2x1 and Si(111)7x7. We find that simple growth occurs up to a critical coverage, independent of temperature. Beyond growth continues to be laminar for deposition at 150 K only, while island formation is observed at temperatures at and above room temperature. the Si(111)7x7 reconstruction seems unperturbed by Sn deposition at room temperature while the Si(100)2x1 begins to order. However, the reordering, a necessary condition for perfect growth, is incomplete.