Scale-up of a parallel plate RF plasma etching reactor by using reactive gas flow simulations

A parallel plate/narrow gap radio frequency (RF) (400 kHz)-plasma SiO2 etch ing reactor for a 200 mm diam wafer was scaled up to that for a 300 mm diam wafer according to numerical simulations of gas flow and mass transfer for the etching gas CF4/Ar. Experimental measurements of this reactor (for a 3 00 mm diam wafer) agree well with the simulated etching rate anti etching, uniformity on the 300 mm diam wafer. It was shown that the reactor for a 30 0 mm diam wafer could be scaled up only in the radial direction. It was als o clarified that gas inlet showerhead radius and plasma radius correlativel y affect the etching rate at the edge of the wafer; they are therefore key parameters that must be controlled to get better uniformity of etching rate . (C) 2001 The Electrochemical Society. [DOI: 10.1149/1.1383556] All rights reserved.