A method for etching a target material in the presence of a structural material with improved selectivity uses a vapor phase etchant and a co-etchant. Embodiments of the method exhibit improved selectivities of from at least about 2-times to at least about 100-times compared with a similar etching process...http://www.google.com.au/patents/US7566664?utm_source=gb-gplus-sharePatent US7566664 - Selective etching of MEMS using gaseous halides and reactive co-etchants
