Integrity of hafnium silicate/silicon dioxide ultrathin films on Si

Abstract

Hafnium interdiffusion studies from hafnium silicate into silicon Appl. Phys. Lett. 79, 4192 (2001); 10.1063/1.1425466 Density difference related to humidity during dry oxidation for ultrathin silicon oxide films Density of ultradry ultrathin silicon oxide films and its correlation with reliability Rapid thermal annealing at 1000°C of (HfO 2 ) 1Ϫx (SiO 2 ) x pseudobinary alloy films deposited on Si were performed in N 2 or O 2 atmospheres. The effects on the atomic transport, structure, and composition were investigated using isotopic substitution of oxygen, high-resolution transmission electron microscopy, nuclear reaction analyses, narrow nuclear reaction resonance profiling, and grazing angle x-ray reflection.

Hydrogen and deuterium incorporation and transport in hafnium-based dielectric films on silicon

“…Table I Table I reveals that there is a one order of magnitude larger reduction in the amount of incorporated 2 H in both UVOZ -HfSiO and UVOZ-HfSiON structures when submitted to rapid thermal preannealing at 1000°C in N 2 or N 2 followed by O 2 , as compared to those preannealed at 400-500°C. These data indicate a strong reduction in defect density in these dielectric films, which may be correlated to the previously observed 19 (not shown), decreases significantly during annealing in O 2 at 1000°C. The 2 H loading in as-prepared react-and UVOZsamples cannot be directly compared for different reasons, including the following: (i) The very large difference in thickness of the two groups of samples, (ii) the differences in relative oxygen and nitrogen content and defect structures in the two groups, resulting from the two different preparation routes, and (iii) the thickness differences within the UVOZHfSiO and HfSiON group of samples, which may require a normalization to equal thicknesses.…”

“…We particularly examine the effect on the 1 H-and 2 H-incorporation dynamics of typical rapid thermal annealing at 1000°C responsible for source and drain dopant activation, which also yields a densification of hafnium silicate gate dielectric films. 19 The investigated thin films were all sputtered from a HfSi target in the following routes: Hydrogen concentrations versus depth were determined by nuclear resonant reaction profiling (NRP) using the 1 H͑ 15 N,␣␥͒ 12 C nuclear reaction near the resonance at 6.385 MeV, 14 while deuterium areal densities were determined by NRA using the 2 H͑ 3 He, p͒ 4 He nuclear reaction 13 at 700 keV. Samples were annealed in a Joule-effect heated furnace or by rapid thermal annealing, in vacuum (p ϳ 10 −7 mbar, vacuum annealing), in 50 mbar of N 2 (N 2 annealing), or in 50 mbar of O 2 (O 2 annealing).…”

High dielectric constant oxides

“…This greatly reduces the oxygen diffusion rate. The diffusion rates of Hf, O, B and P in HfO 2 and Hf silicate have been measured after implantation by secondary ion mass spectroscopy (SIMS) and nuclear reaction profiling [43][44][45][46][47] to confirm these observations. The mixing of oxide and Si layers has also been studied by Medium Energy Ion Scattering (MEIS) which measures the element profile.…”

The structural and interfacial properties of HfO2/Si by the plasma oxidation of sputtered metallic Hf thin films

“…High-quality HfO 2 thin films have been deposited by PVD [13,14], CVD [15], Metal-organic chemical-vapor-depositon (MOCVD) [16] and atomic-layer deposition [17]. Among these deposition techniques, one of the serious problems is the interfacial layer growth due to the oxidization of the Si substrate surface, which is brought about in excess oxygen ambient at elevated temperature.…”