In situ Auger electron spectroscopy of Si and SiO₂ surfaces plasma etched in CF₄-H₂ glow discharges

In situ Auger electron spectroscopy has been combined with in situ etch-rate measurements, using quartz crystal microbalances, to study the plasma etching of Si and SiO2 surfaces rf biased at -100 V in CF 4-H2 glow discharges. More carbon deposition was observed on the Si surface relative to the SiO2 surface as hydrogen was added to the CF4 plasma. This observation is consistent with a previously suggested model for the large SiO2-to-Si etch-rate ratios observed in CF4-H2 discharges.