Lam Research Corporation
ION BEAM ETCHING WITH GAS TREATMENT AND PULSING

Abstract:

One or more layers of a magnetic random access memory (MRAM) stack on a substrate are etched by ion beam etching. An ion beam of an inert gas is generated in an ion beam source chamber and applied to a substrate in a continuous or pulsed manner. Without passing through the ion beam source chamber, a reactive gas is flowed directly into a processing chamber in which the substrate is located, where the reactive gas is pulsed or continuously provided into the processing chamber. The reactive gas may include a carbon-containing gas having a hydroxyl group that is flowed towards the substrate to limit re-deposition of sputtered atoms on exposed surfaces of the substrate from ion beam etching.