Uniform Tetragonal WSi2 Layers Formed by RTA (Rapid Thermal Annealing)

摘要

The use of BOE 500 solution for etching the Silicone(100) wafer prior to tungsten deposition has resulted in the evolution of a formation process with reproducible resistivities amongst the lowest reported (30 - 35 micro ohms per centimeter) for thin film WSi2 layers grown on a silicon substrate. This result was achieved without using evaporation in a UHV environment, or a co-sputtering deposition, either of which normally give better resistivities. The growth process has been shown to be diffusion controlled, with the average grain size correlating with the film resistivity. Oxygen, although not detectable by Auger in the as-deposited film, tends to first pile-up at the interface upon SWi2 formation, followed by expulsion upon prolonged annealing times. Furthermore, rapid thermal annealing reduces the reaction time from 30 minutes for conventional furnace annealing reduces the reaction time from minutes for conventional furnace anneal to 25 - 50 seconds. Keywords: Oxidation; Wafers; Microelectronics; Reprints.