Method for etching chemically inert metal oxides

Abstract

A system and method for patterning metal oxide materials in a semiconductor structure. The method comprises a first step of depositing a layer of metal oxide material over a substrate. Then, a patterned mask layer is formed over the metal oxide layer leaving one or more first regions of the metal oxide layer exposed. The exposed first regions of the metal oxide layer are then subjected to an energetic particle bombardment process to thereby damage the first regions of the metal oxide layer. The exposed and damaged first regions of the metal oxide layer are then removed by a chemical etch. Advantageously, the system and method is implemented to provide high-k dielectric materials in small-scale semiconductor devices. Besides using the ion implantation damage (I/I damage) plus wet etch technique to metal oxides (including metal oxides not previously etchable by wet methods), other damage methods including lower energy, plasma-based ion bombardment, may be implemented. Plasma-based ion bombardment typically uses simpler and cheaper tooling, and results in less collateral damage to underlying structures as the damage profile can be more easily localized to the depth of the thin metal oxide film.