Patent ID: 7255799

Claim:
A method for selectively covering a micro machined surface on a die comprising an upper face and at least one etched recess located in the upper face, the method comprising: applying a film of negative photoresist onto the upper face, the film of negative photoresist covering the at least one etched recess without filling the at least one etched recess; exposing the film of negative photoresist to ultraviolet radiation through a first mask, the first mask having a window coextensive with at least the at least one etched recess, thereby polymerizing a region of the film of negative photoresist covering the at least one etched recess; removing a non-polymerized portion of the film of negative photoresist from the upper face, thereby leaving a covering of polymerized film over the at least one etched recess; applying a layer of lift off resist over the upper face of the die and over the covering; and applying a layer of positive photoresist over the layer of lift off resist.