Gaseous plasma etching of aluminum and aluminum oxide

摘要

Gaseous plasma etching of aluminum with conventional plasma etch gases has not hitherto been commercially possible due to a layer of aluminum oxide (Al2O3) which forms on freshly prepared aluminum surfaces. By first plasma etching in the presence of a gaseous trihalide, preferably in a so-called "pancake" or radial-flow type reactor, the oxide layer is removed. Aluminum etching can then continue, either with or without plasma conditions, depending upon the etch gas used.