Hafnium interdiffusion studies from hafnium silicate into silicon

Abstract

The interdiffusion of Hf and Si from high-κ gate dielectric candidate (HfO2)1−x(SiO2)x thin films deposited on Si (100) was studied using x-ray photoelectron spectroscopy, time-of-flight secondary ion mass spectrometry, high resolution transmission electron microscopy, and Rutherford backscattering spectrometry in combination with chemical etching. After extreme rapid and conventional furnace thermal annealing treatments, Hf incorporation into Si is limited to less than 0.5–1 nm from the interface. Implications for high-κ gate dielectric applications are also discussed.