| abstract |
Embodiments of the invention include a method for fabricating metal structuresnsuch as electrodes on a substrate. Typical fabrication methods of this kind includendepositing a seed layer on a substrate, depositing a photoresist on the seed layer,npatterning the photoresist, forming the metal structure according to the patternednphotoresist using electroplating techniques, and then removing the photoresist to yield thenmetal structure. However, underplating often occurs during electroplating, and the hardnbaking requirements for treating the photoresist cause photoresist deformation that isntranslated into deformed structures. Embodiments of the invention deposit a sacrificialnlayer on the substrate's seed layer to promote greater adhesion between the seed layer andnthe subsequently deposited photoresist layer. The sacrificial layer, which includesntitanium or other suitable material, improves adhesion between the seed layer and thenphotoresist to the extent that the photoresist hardbaking requirement is eliminated and thenunderplating contributions caused by layer separation are suppressed. Also, the sacrificialnlayer is made of a material that is unsuitable for electroplating metal materials thereon,nthus discouraging metal materials from electroplating to exposed regions in the event thatnsome layer separation does occur. |