Reduction of particle generation in capacitively coupled plasma etching reactor

In this paper, we report a method to prevent the formation of particles in a capacitively coupled etching (CCP) reactor. We investigate the mechanism of particle generation and concluded that thermal expansion of the upper electrode during etching induces particle formation. We introduce a -20degC coolant behind the sheet heaters to relax the heat flow from the plasma to the upper electrode. After introducing the -20degC coolant in production, the number of particles decreases by approximately 50%. Due to the stable particle level, the production uptime increases by 15%.