THIN GROUP IV SEMICONDUCTOR STRUCTURES

摘要

Thin group IV semiconductor structures are provided comprising a thin Si substrate and a second region formed directly on the Si substrate, where the second region comprises either (i) a Ge1-xSnx layer; or (ii) a Ge layer having a threading dislocation density of less than about 105/cm2, and the effective bandgap of the second region is less than the effective bandgap of the Si substrate. Further, methods for preparing the thin group IV semiconductor structures are provided. Such structures are useful, for example, as components of solar cells.