Solid-phase epitaxial growth of Ge on H-terminated and oxidized Si(100) surfaces

Abstract

Thin Ge films with a thickness of about 10 nm were deposited on hydrogen-terminated and oxidized Si(100) surfaces using electron beams. We prepared the above two types of surfaces by chemical treatments and measured the amounts of oxygen and hydrogen by ion channeling and nuclear resonant reaction of1H(15N, αγ)12C, respectively. They were estimated to be 1.2 nm (SiO2) and 2.3 ± 1015 Hcm2 (about 3 monolayers). The samples were post-annealed at 600, 800, 900 and 1000°C for 5 s in a high vacuum. The hydrogen-terminated Si(100) has a strongly stable hydride structure, which remains at the Ge/Si interface up to 900°C. This very thin and stable Si-hydride surface brings significant effects to improve the surface morphology and crystallinity and to hold steep interfaces compared with the oxidized surface.