Abstract
Earlier papers have shown that high etch rates and controlled profiles can be obtained with the rf hollow cathode configuration. The etch selectivity of SiO2 with respect to Si was of the order 5 to 1 with a CF4 etch gas, and this paper investigates the effect of H2 and O2 gas additions on the etch selectivity in a symmetrical hollow cathode system. CF4/O2 mixtures cause the SiO2/Si etch rate ratio to vary between 0.75 and 1.5. CF4/H2 mixtures have to date yielded a SiO2/Si etch ratio of 16. The etched angle in CF4/H2 mixtures is controlled as in CF4 hollow cathode etching, and it is shown that this control is caused by the competitive coating process.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call