Thick film layers and methods relating thereto
AssigneeLexmark International, Inc.
InventorsGirish S. Patil, Sean T. Weaver, Rich Wells
Life of this patent
Estimating the term…
Abstract
Thick film layers for a micro-fluid ejection head, micro-fluid ejection heads, and methods for making micro-fluid ejection head and thick film layers. One such thick film layer is derived from a difunctional epoxy component having a weight average molecular weight ranging from about 2500 to about 4000 Daltons, a photoacid generator, an aryl ketone solvent, and an adhesion enhancing component. One such thick film layer has a cross-link density upon curing that increases the dimensional stability of the thick film layer sufficient to provide flow features therein having substantially vertical walls.
Claims5
A method for increasing the planarity of a surface of a thick film layer after photoimaging and developing flow features therein for a micro-fluid ejection head, the method comprising:
- applying a negative photoresist layer to a device surface of a substrate, wherein the negative photoresist layer is derived from a multi-functional epoxy compound, a difunctional epoxy compound, a photoacid generator devoid of aryl sulfonium salts, an adhesion enhancer, and an aryl ketone solvent;
- heating the photoresist layer to remove at least a portion of the solvent;
- cooling the photoresist layer;
- etching a fluid feed slot through the substrate from a backside of the substrate opposite the device surface, wherein the heated and cooled photoresist layer serves as an etch stop to the etching;
- and thereafter
- imaging flow features in the photoresist layer;
- and
- developing the imaged photoresist layer to provide the plurality of flow features therein and the substantially planar thick film layer surface.
Dependencies are inferred from the claim text.