Development of nanostructured Ge1-xSnx alloy using ion beam techniques for band gap engineering

Abstract

Silicon Photonics is a disruptive technology that promises to revolutionize high performance computing by taking advantage of light in data transmission. Due to inefficient emission from Si, an outstanding quest has been the development of non-equilibrium group IV nanoscale alloy in achieving new functionalities, such as the formation of a direct bandgap elemental semiconductor. To address this challenge, we propose to use ion beam processing to fabricate Ge1−xSnx alloy nanowires in Ge wafers as a potential material structure for building Si-compatible light sources. Preliminary investigations of ion implantation of Sn into Ge crystals using Rutherford backscattering technique (RBS), their structural properties examined through scanning electron microscopy (SEM) and Sn distribution using energy-dispersive X-ray spectroscopy (EDX), crystallinity and Sn substitutionality using Raman spectroscopy is presented. This non-equilibrium induction of Sn in Ge, a bottom-up approach to formation of direct bandgap Ge1−xSnx nanowires opens up unlimited possibilities in group IV photonics.