The etch rates of TiN and SiO2 and TiN/SiO2 selectivity as a function of Cl2 and N2 flow rate, bias power, and pressure were studied. The bias power affected the etch rate and the selectivity between TiN and SiO2 can be achieved at low bias power. The etch rate increased with increasing pressure while the etch selectivity decreased as the pressure increased. This may be due to the atomic Cl radical density, the ion flux and the ion energy. Chlorine and nitrogen flow rate have no significant effect on etch selectivity and etch rate, respectively.
|Number of pages
|Journal of Vacuum Science and Technology, Part A: Vacuum, Surfaces and Films
|Published - 1 Mar 2001