Improvements of Electrical Characteristics of Hf/p-Si(100) Interfaces by H-Termination

Effects of H-termination of Si(100) surfaces on electrical characteristics of Hf/p-Si interfaces have been examined. It is confirmed by high-resolution electron energy loss spectroscopy (HREELS) and X-ray photoelectron spectroscopy (XPS) that the H-terminated surface, prepared by wet treatments in HF and then in water, is very stable for native oxidation and adsorption of oxygen. Effective dielectric layer thicknesses of H-terminated Hf/p-Si interfaces are 1/4-1/3 smaller than those of nonterminated ones, and the ideality factors in current-voltage characteristics are very close to unity. Deep levels at E v+0.14, E v+0.43 and E v+0.52 eV are observed for 460° C-annealed diodes by deep-level transient spectroscopy (DLTS), the densities of which are reduced below the detection limit by annealing at 580° C. It can be concluded that the H-termination is markedly effective in improving electrical characteristics of Hf/p-Si interfaces.