X-ray photoelectron spectroscopic characterization of ultra-thin silicon oxide films on a Mo(100) surface

Ultra-thin films of silicon oxides supported on a Mo(100) surface have been studied using X-ray photoelectron spectroscopy (XPS). The films were synthesized by evaporating Si onto the Mo surface in oxygen ambient and were subsequently characterized using XPS with respect to the chemical states of silicon and the composition of the film. It has been found that the silicon oxide, prepared at room temperature with a silicon deposition rate of ∼ 1.2 A/min and an oxygen pressure of 2 × 10−5 Torr, consisted of predominantly silicon dioxide with a small fraction of suboxides. Annealing to ∼ 1300 K yielded a stoichiometric film of SiO2. The suboxides are believed to further react with oxygen forming SiO2 at an elevated temperature.

[1]  Stephen H. Garofalini,et al.  A molecular dynamics simulation of the vitreous silica surface , 1983 .

[2]  J. Rowe,et al.  Electronic transitions of oxygen adsorbed on clean silicon (111) and (100) surfaces , 1974 .

[3]  V. Bermudez.  Growth, structure and oxidation of ordered silicon layers on nickel (001) , 1990 .

[4]  D. Goodman,et al.  A new design for a multitechnique ultrahigh vacuum surface analysis chamber with high pressure capabilities , 1992 .

[5]  S. I. Raider,et al.  Electron mean escape depths from x−ray photoelectron spectra of thermally oxidized silicon dioxide films on silicon , 1975 .

[6]  A. Feldman,et al.  Bonding structure of silicon oxide films , 1988 .

[7]  Michael F. Hochella,et al.  A reassessment of electron escape depths in silicon and thermally grown silicon dioxide thin films , 1988 .

[8]  R. S. Bauer,et al.  Evidence of SiO at the Si—oxide interface by surface soft x-ray absorption near edge spectroscopy , 1980 .

[9]  F. Bechstedt,et al.  Interpretation of XPS core level shifts and structure of thin silicon oxide layers , 1985 .

[10]  W. F. Egelhoff.  Core-level binding-energy shifts at surfaces and in solids , 1987 .

[11]  M. Grunze,et al.  Chemical cleaning of metal surfaces in vacuum systems by exposure to reactive gases , 1988 .

[12]  Aoto Nahomi,et al.  In-depth profiling of the SiO2/Si-interface electronic structure using low-energy electron energy loss spectroscopy , 1990 .

[13]  A. M. Stoneham,et al.  Oxidation of silicon , 1989 .

[14]  F. Himpsel,et al.  Multiple-bonding configurations for oxygen on silicon surfaces , 1983 .

[15]  J. Dieleman,et al.  An in situ infrared study of the room temperature oxidation of silicon with atomic and molecular oxygen , 1989 .

[16]  C. A. Estrada,et al.  Synthesis and characterization of ultra-thin MgO films on Mo(100) , 1991 .

[17]  G. Lucovsky,et al.  Infrared spectroscopic study of SiOx films produced by plasma enhanced chemical vapor deposition , 1986 .

[18]  W. Braun,et al.  Chemical structure of ultrathin thermally grown oxides on a Si(100)-wafer using core level photoemission , 1987 .

[19]  Anupam Madhukar,et al.  High-Resolution X-Ray Photoelectron Spectroscopy as a Probe of Local Atomic Structure: Application to Amorphous Si O 2 and the Si-Si O 2 Interface , 1979 .

[20]  Katsuhisa Usami,et al.  Infrared absorption spectra and compositions of evaporated silicon oxides (SiOx) , 1984 .

[21]  C. R. Helms,et al.  Electron energy loss spectroscopy studies of the Si‐SiO2 interface , 1979 .