Etching deposited metals requires a more aggressive chemical attack than etching SiO2 during device fabrication. Consequently, the resists need to be tougher. The process of silyation is frequently performed to harden the photoresist before it is subjected to etching. During silyation, silicon atoms are introduced into the surface of the organic resist. This process can be accomplished with either wet or dry procedures. Most commonly, a wet bath using either hexamethyldisilazane (HMDS) or silazone in xylene is used.
The following are the potential hazards of silyation.Back to Top