Nanothick Layer Transfer of Hydrogen-Implanted Wafer Using Polysilicon Sacrificial Layer

Abstract

A fabrication method of 2-D nanostructure materials applied for forming nanothick SOI materials without using post-thinning processes is presented in this paper. The thickness of SOI layer is precisely controlled by a polysilicon layer as a sacrificial layer in the implantation step to acquire a desirable implant depth. Polysilicon layer was initially deposited on the thermal oxidized surface of silicon wafer prior to the ion implantation step with 4×10¹⁶ /cm⁻², 160KeV, H₂⁺ ions. The as-implanted wafer was contained a hydrogen-rich buried layer which depth from the top surface is less than 100 nm. Before this as-implanted wafer being bonded with a handle wafer, the polysilicon layer was removed by a wet etching method. A nanothick silicon layer was then successfully transferred onto a handle wafer under 10-minute microwave irradiation after the bonding step. The thickness of the final transferred silicon layer was 100 nm measured by transmission electron microscopy (TEM).