Photoimageable Nozzle Members and Methods Relating Thereto

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 having a thickness ranging from about 10 to about 30 microns and being derived from a second photoresist formulation comprising a second di-functional epoxy compound, a relatively high molecular weight polyhydroxy ether, 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 photorsist layer to provide a photoresist nozzle member adjacent the thick film layer.