Comparison of F 2‐Based Gases for High‐Rate Dry Etching of Si

Four different ‐based gases were examined for high rate inductively coupled plasma (ICP) etching of Si. Etch rates up to ∼8 μm/mi were achieved with pure discharges at high source power (1500 W) and pressure (35 mTorr). A direct comparison of the four feedstock gases under the same plasma conditions showed the Si etch rate to increase in the order .This is in good correlation with the average bond energies of the gases, except for , which is the least strongly bound. Optical emission spectroscopy showed that the ICP source efficiently dissociated , but the etched Si surface morphologies were significantly worse with this gas than with the other three gases. © 1999 The Electrochemical Society. All rights reserved.