Selective reactive etching of metal or semiconductor - using plasma contg. chlorine, bromine or iodine (cpds.) avoids undercutting

摘要

In the selective removal of metal and/or semiconductor materials by reactive ion etching using a photoresist or dielectric film, e.g. SiO2, Si3H4 or Al2O3 as mask, the improvement comprises subjecting the substrate to be treated to cathodic sputtering under the action of a plasma or an atmos. under preliminary vacuum conditions, consisting of CCl4, HCl, Cl2, CBr4, HBr, Br2, CI4, I2, mixts. and cpds. of these, without addn. of F2 and F cpds. Method is used in the prodn. of monolithic semiconductor circuits. A relatively high etching rate is obtd. without undercutting.