Fast anisotropic etching of silicon in an inductively coupled plasma reactor

A 13.56 MHz rf inductively coupled diffusion plasma confined by a weak magnetic field is shown to produce high etch rates and high plasma densities. With a substrate bias of −160 V and 1 mTorr of pure SF6, silicon has been etched anisotropically at a rate of 0.7 μm min−1 with a selectivity to SiO2 of about 5.