Realization of freestanding InP membranes on Si by low-temperature wafer bonding and stress analysis using micro-Raman spectroscopy

We present a method to realize freestanding InP membranes on Si substrate by combination of low-temperature wafer bonding, layer transfer, and wet chemical release processes. The removal of InP substrate and sacrificial etching of an InGaAs layer defines the 2.0μm InP thin layer bonded to Si. The InP membranes are subsequently released by a two-step wet etching process and the surface stress profiling in these freestanding membranes has been carried out by high spectral resolution micro-Raman measurements. Realization of such micromechanical structures on Si platform would be suitable for the integration of InP-based photonic devices on large area Si-based microelectronic systems.