Dry film formulation

A method for making an improved fluidic ejection head, the method comprising the steps of:

• applying a photoresist layer to a release film, wherein the photoresist layer is derived from a photoimageable dry film formulation comprising a multi-functional epoxy compound, a photoacid generator, a silane oligomer adhesion enhancer is a gamma-glycidoxypropyltrimethoxysilane oligomer of the formula
• wherein n ranges from 1 to 4, and an aryl ketone solvent;
• drying the photoimageable dry film formulation on the release film layer to provide a thick film layer;
• laminating the thick film layer to a flow feature layer on a semiconductor substrate;
• removing the release film from the thick film layer;
• imaging a nozzle hole in the thick film layer;
• and
• developing the imaged thick film layer to provide a nozzle plate for the fluidic ejection head.

A fluidic ejection head for ejecting a fluid composition comprising:

• a semiconductor substrate containing fluid ejection devices thereon,
• a flow feature layer disposed on the semiconductor substrate, and
• a thick film layer laminated to the flow feature layer, wherein the thick film layer is derived from a photoimageable dry film formulation comprising a multifunctional epoxy compound, a photoinitiator capable of generating a cation, a non-photoreactive solvent, and from about 0.5 to about 5% by weight a silane oligomer adhesion enhancer based on a total weight of the photoimageable dry film formulation before drying, wherein the silane oligomer adhesion enhancer is a gamma-glycidoxypropyltrimethoxysilane oligomer of the formula
• wherein n ranges from 1 to 4.