Author :
Kaushik, Vidya S. ; O´Sullivan, Barry J. ; Pourtois, Geoffrey ; Van Hoornick, Nausikaä ; Delabie, Annelies ; Van Elshocht, Sven ; Deweerd, Wim ; Schram, Tom ; Pantisano, Luigi ; Rohr, Erika ; Ragnarsson, Lars-Ake ; De Gendt, Stefan ; Heyns, Marc
Abstract :
In this paper, an effective technique and methodology for the estimation of fixed charge components in high-k stacks was demonstrated by varying both the SiO2 and high-k dielectric thicknesses. The SiO2 thickness was scaled on a single wafer by uniformly changing the etch time of a thermally grown SiO2 layer across the wafer. This minimized wafer-to-wafer variations and enables acquisition of statistically significant datasets. Layers with different thickness of both the nitrided and non-nitrided hafnium-silicate layers were then grown on these wafers to estimate all the interfacial and bulk charge components. The reproducibility and validity of this technique were demonstrated, and this method was used to compare the fixed charge levels in Hf-silicates (HfSiO) and nitrided-Hf-silicate (HfSiON) layers
Keywords :
annealing; hafnium compounds; high-k dielectric thin films; silicon compounds; HfSiON; SiO2; charge components; fixed charge densities estimation; flatband voltage; hafnium-silicate gate dielectrics; high-k dielectric thicknesses; high-k stacks; interface layer; oxide charge; slant-etch; thickness variation; wafer-to-wafer variations; Channel bank filters; Dielectric measurements; Electrodes; Etching; High K dielectric materials; High-K gate dielectrics; Microelectronics; Reproducibility of results; Semiconductor device modeling; Threshold voltage; Flatband voltage; hafnium silicate; high-; interface layer; oxide charge; slant-etch; thickness variation;
