Epitaxial Ge-rich silicon layers after dry oxidation of Ge implanted silicon

Abstract We report on formation of epi-layer of Si x Ge 1-x by taking standard procedure in CMOS technology. The competitive process of solid solubility of Ge dopant into Si and SiO 2 is the key to engineer atomically sharp, low defect very thin epitaxial layer at the interface of oxide-Si. Oxidation time process was used to control the distribution of the doped Ge ions at the interface of Si with oxide and in the oxide layer. Implanted samples (35 keV and 1 × 10 16 Ge + /cm 2 ) were oxidized at 1050 °C for 30–90 min. RBS-Channeling analysis shows two separate peaks of Ge corresponds to different depths after oxidation. Corroborate with high resolution microscopy and elemental analysis, we determined the first peak as enriched layer of Si x Ge 1-x at the interface of SiO 2 Si. Less than 10 nm epitaxially grown interfacial layer is very low in defects, and Ge ions are fully substituted into the host lattice. The second peak originated from diffusion of Ge into SiO 2 resulted in a segregated layer containing Ge in oxide film. Technological demand on forming Si x Ge 1-x layer for CMOS application through standard routes is what we address in this research.