Non-photosensitive siloxane coating for processing hydrophobic photoimageable nozzle plate
View Patent ↗A method of forming a patterned photoresist layer having a hydrophobic surface is provided. The method includes forming a photoresist layer on a substrate and image patterning. The photoresist layer may comprise a polymeric material. The imaged photoresist layer may then undergo a two-stage post-exposure bake. A surface treatment may be performed on the photoresist layer in between the two-stage post-exposure bake. The surface treatment may include applying a siloxane solution on a partially post-exposure baked photoresist layer. The post-exposure baked photoresist layer may then be developed to form the patterned photoresist layer. The method may be used to form a hydrophobic photoimageable nozzle plate of a micro-fluid ejection head having improved mechanical properties and stable hydrophobic properties.
1. A method of forming a patterned photoresist layer having a hydrophobic surface, the method comprising:
forming a photoresist layer on a substrate;
image patterning the photoresist layer;
performing first stage post-exposure bake to the imaged photoresist layer, wherein the imaged photoresist layer is partially baked;
surface treating the partially post-exposure baked photoresist layer;
performing second stage post-exposure bake to the surface treated partially post-exposure baked photoresist layer; and
developing the second stage post-exposure baked photoresist layer in a single step.
2. The method of claim 1 , wherein the photoresist layer comprises a polymeric material with photoacid generator.
3. The method of claim 1 , wherein the surface treating includes applying siloxane solution on a top surface of the partially post-exposure baked photoresist layer, the siloxane solution comprising an epoxy functionalized siloxane resin dissolved in a hydrocarbon carrier solvent, the epoxy functionalized siloxane resin having at least two epoxy group per molecule.
4. The method of claim 3 , wherein the epoxy functionalized siloxane resin comprises a terminal glycidyl ether group.
5. The method of claim 3 , wherein the epoxy functionalized siloxane resin comprises a pendant glycidyl ether group.
6. The method of claim 3 , wherein the epoxy functionalized siloxane resin comprises a pendant cyclohexene oxide group.
7. The method of claim 3 , wherein the epoxy functionalized siloxane resin comprises a terminal cyclohexene oxide group.
8. The method of claim 3 , wherein the hydrocarbon carrier solvent comprises aliphatic hydrocarbon.
9. The method of claim 3 , wherein the hydrocarbon carrier solvent comprises aromatic hydrocarbon.
10. The method of claim 3 , wherein the hydrocarbon carrier solvent comprises a mixture of aliphatic hydrocarbon and aromatic hydrocarbon.
11. The method of claim 3 , wherein the siloxane solution does not contain photosensitive additive.
12. A method of forming a hydrophobic nozzle plate for a micro-fluid ejection head, comprising:
laminating a photoresist dry film on a flow feature layer of a micro-fluid ejection head structure;
image patterning the laminated photoresist dry film; performing first stage post-exposure bake to the imaged photoresist dry film, wherein the imaged photoresist dry film is partially baked;
surface treating the partially post-exposure baked photoresist dry film;
performing second stage post-exposure bake to the surface treated partially post-exposure baked photoresist dry film; and
developing the second stage post-exposure baked photoresist dry film to form nozzles therein in a single step.
13. The method of claim 12 , wherein the photoresist dry film comprises a polymeric material with photoacid generator.
14. The method of claim 12 , wherein the surface treating includes applying siloxane solution on a top surface of the partially post-exposure baked photoresist layer, the siloxane solution comprising an epoxy functionalized siloxane resin dissolved in a hydrocarbon carrier solvent, the epoxy functionalized siloxane resin having at least two epoxy groups per molecule.
15. The method of claim 14 , wherein the epoxy functionalized siloxane resin comprises a terminal glycidyl ether group.
16. The method of claim 14 , wherein the epoxy functionalized siloxane resin comprises a pendant glycidyl ether group.
17. The method of claim 14 , wherein the epoxy functionalized siloxane resin comprises a pendant cyclohexene oxide group.
18. The method of claim 14 , wherein the epoxy functionalized siloxane resin comprises a terminal cyclohexene oxide group.
19. The method of claim 14 , wherein the hydrocarbon carrier solvent comprises aliphatic hydrocarbon.
20. The method of claim 14 , wherein the hydrocarbon carrier solvent comprises aromatic hydrocarbon solvent.
21. The method of claim 14 , wherein the hydrocarbon carrier solvent comprises a mixture of aliphatic hydrocarbon solvent and aromatic hydrocarbon.
22. The method of claim 14 , wherein the siloxane solution does not contain photosensitive additive.