Studies on High-k Gate Stacks by High-resolution Rutherford Backscattering Spectroscopy

Abstract

This thesis is on the study of the characterization of interfaces and surfaces of high-k stacks for the future microelectronics. The changes of the high-k stacks during thermal processing and its mechanism have been experimentally investigated by high-resolution Rutherford Backscattering Spectrometry (HRBS) in combination with isotope tracing. The experimental results are consistent with the theoretical prediction that the silicon will be emitted outward to release the stress which is induced by the interface Si oxidation. Then, we studied the potential method, oxygen-gettering by Ti overlayer, for controlling the interface SiO2 thickness. Furthermore, we proposed a Time-Of-Flight (TOF) detector system for application on crystallographic analysis. TOF-RBS system is capable to analyze the sample’s crystallographic and chemical information even at the near surface of the sample, which is strongly required by the future microelectronics industry. In this chapter, brief introduction to the high-k stacks and the outline of this thesis are described.