Tensile-strained germanium-on-insulator substrate fabrication for silicon-compatible optoelectronics

Abstract

We present a method to fabricate tensile-strained germanium-oninsulator (GOI) substrates using heteroepitaxy and layer transfer techniques.The motivation is to obtain a high-quality wafer-scale GOI platform suitable for silicon-compatible optoelectronic device fabrication.Crystal quality is assessed using X-Ray Diffraction (XRD) and Transmission Electron Microscopy.A biaxial tensile film strain of 0.16% is verified by XRD.Suitability for device manufacturing is demonstrated through fabrication and characterization of metal-semiconductor-metal photodetectors that exhibit photoresponse beyond 1.55 μm.The substrate fabrication process is compatible with complementary metal-oxidesemiconductor manufacturing and represents a potential route to wafer-scale integration of silicon-compatible optoelectronics.