Spectroscopic Ellipsometry Characterization of High‐k films on SiO2/Si

Spectroscopic ellipsometry (SE) with VUV wavelength region has been used to characterize high‐k films grown on SiO2/Si. The high‐k stack thickness measurements by SE are compared to thickness measurements derived from angle resolved x‐ray photoemission spectroscopy. The optical properties of hafnium silicate change with silicate concentration, which is the mechanism for SE to measure this quantity. Other factors that affect high‐k optical properties such as N concentration and annealing are also investigated.