Simultaneous RHEED–AES–QMS study on epitaxial Si film growth on Si(111) and sapphire (1102) surfaces by partially ionized vapour deposition

The role of simultaneous measurements of the chemical composition of a surface by AES, surface crystalline structure by RHEED, and released species by QMS are presented. A molecular beam of Si is effused from a partially ionized vapor deposition (PIVD) source consisting of a Kundsen cell and an electron-impact-type ionization chamber. The 7×7 structure of a Si(111) substrate at 1100 K changes into a broad 1×1 structure after vacuum deposition (VD) of 15 nm of Si while the epitaxial temperature can be lowered to 620 K (PIVD) in a 0.5% ionized atomic vapor with a typical deposition rate and acceleration energy of 0.3 nm/min and 100 eV, respectively. Epitaxial growth of Si on sapphire (11̄02) can be observed at 850 (VD) and at 700 K(PIVD), with a 1% ionized atomic vapor. The Auger spectra during deposition at 870 K remarkably shows that O and Al are reacted with Si on the film.