Electrical characterization of hexagonal SiGe

We report electrical measurements on hexagonal silicon-germanium (hex-SiGe), a group IV alloy with direct bandgap. Electrical contacts are formed by metal alloying and doping is achieved using ion implantation. The metastable hex-SiGe phase is recovered after implantation by solid phase recrystallization. Independent of the metal used, contacts on n-type samples resulted in Schottky barriers due to Fermi level pinning of hex-SiGe. Overall, this constitutes a first step toward use of hex-SiGe for optoelectronic applications.