Patent ID: 7794613

Claim:
A method of fabricating a printhead having a hydrophobic ink ejection face, the method comprising the steps of: (a) providing a partially-fabricated printhead comprising a plurality of nozzle chambers filled with sacrificial material and a relatively hydrophilic nozzle surface, said nozzle surface at least partially defining the ink ejection face; (b) depositing a layer of relatively hydrophobic polymeric material onto the nozzle surface; (c) defining a plurality of nozzle openings in said nozzle surface by the sub-steps of; (c 1 ) depositing a photoresist mask on said polymeric material; (c 2 ) patterning said photoresist mask so as to unmask said polymeric material in a plurality of nozzle opening regions; (c 3 ) etching said unmasked polymeric material and said underlying nozzle surface to define the plurality of nozzle openings; and (d) removing said sacrificial material and said photoresist mask by ashing in an oxidative plasma, said polymeric material being resistant to removal by said oxidative plasma, thereby providing a printhead having a relatively hydrophobic ink ejection face, wherein said polymeric material is selected from the group consisting of: polymerized siloxanes.