US Patent 7497961 Method of making an inkjet printhead

A method of making an inkjet printhead comprises forming at least one ink ejection element 18 on a surface 14 of a substrate 10 and forming a slot 12 in the substrate to provide fluid communication between an ink supply and the ink ejection element. A protective coating 26 is applied to the surface of the substrate prior to forming the slot. The protective coating comprises a non-polymeric material which is capable of forming a covalent bond with the substrate and is removed from the substrate without damaging the ink ejection element following slot formation.