Properties of extremely thin silicon layer in silicon-on-insulator structure formed by smart-cut technology

The aim of the report is a creation of extremely thin silicon-on-insulator (SOI) structures for quantum devices with layer-by-layer oxidation of smart-cut SOI wafers. The present work deals with investigation of structural, optical and electronic properties of SOI structures by HRTEM, RBS, and spectroscopic ellipsometry (SE), Hall and Pseudo-MOSFET measurements. It is demonstrated that this technology of SOI structure preparation provides a high flatness of interface between buried oxide (BOX) and top silicon layer. Layer-by-layer oxidation with subsequent stripping in diluted HF allows us to save the uniformity and flatness of initial SOI layers up to 10 nm film thickness. A further thinning leads to decrease of oxidation rate and non-uniform growth. A mechanism of these processes is suggested.