Patent ID: 8173031

Claim:
A method for making an improved micro-fluid ejection head, the method comprising: applying a first negative photoresist layer adjacent a device surface of a substrate, wherein the first negative photoresist layer is derived from a composition comprising a multi-functional epoxy compound, a first di-functional epoxy compound, a photoacid generator devoid of aryl sulfonium salts, an adhesion enhancer, and an aryl ketone solvent; imaging a plurality of flow features in the first photoresist layer; developing the imaged first photoresist layer to provide the plurality of flow features therein and a substantially planar thick film layer surface; applying a second negative photoresist layer adjacent the thick film layer, the second negative photoresist layer being derived from a second photoresist formulation comprising a second di-functional epoxy compound, a polyhydroxy ether devoid of epoxy group, the photoacid generator devoid of aryl sulfonium salts, the adhesion enhancer, and an aliphatic ketone solvent; imaging a plurality of nozzles in the second photoresist layer; and developing the imaged second photoresist layer to provide a photoresist nozzle member adjacent the thick film layer.