Depth profiles and concentration percentages of SiO2 and SiOx induced by ion bombardment of a silicon (100) target

Very thin-film of silicone oxide is of importance in many microelectronics device fabrication. A 9 keV Ar+ beam was applied to bombard a silicon (100) target ambient oxygen gas. The measurement was performed with a fixed time of bombardment but different oxygen pressure, beam intensity and temperature. An X-ray Photoelectron Spectroscopy (XPS) was employed to analyze the depth profiles and the concentration percentages of SiO2 and SiOx within the bombarded Si (100) samples. The percentage of SiO2 in different depth of the sample is found to be proportional to the oxygen pressure. The thickness of SiO2 film formed at room temperature is larger than the thickness at temperature 650 °C. The net percentages of SiOx, except at the top layer of the surface, are varied in a small difference among different ion-bombardment conditions as the depth below 2 nm.