Method of forming low-stiction nozzle plate for an inkjet printhead
View Patent ↗A method of forming a low-stiction nozzle plate for an inkjet printhead, said nozzle plate having a plurality of nozzle apertures defined therein, each nozzle aperture having a respective nozzle rim, said method comprising the steps of: (a) providing a partially-fabricated printhead comprising a plurality of inkjet nozzle assemblies sealed with roof material; (b) etching partially into said roof material to define simultaneously said nozzle rims and a plurality of stiction-reducing formations; and (c) etching through said roof material to define said nozzle apertures, thereby forming said nozzle plate.
1. A method of forming a low-stiction nozzle plate for an inkjet printhead, said nozzle plate having a plurality of nozzle apertures defined therein, each nozzle aperture having a respective nozzle rim, said method comprising the steps of:
(a) providing a partially-fabricated printhead comprising a plurality of inkjet nozzle assemblies sealed with roof material;
(b) etching partially into said roof material to form simultaneously said nozzle rims of the to-be-formed nozzle apertures and a plurality of stiction-reducing formations; and
(c) etching through said roof material to form said nozzle apertures, thereby forming said nozzle plate.
2. The method of claim 1 , wherein each nozzle rim comprises at least one projection around a perimeter of each nozzle aperture.
3. The method of claim 2 , wherein each nozzle rim comprises a plurality of coaxial projections around a perimeter of each nozzle aperture.
4. The method of claim 2 , wherein said at least one rim projection projects at least 1 micron from said nozzle plate.
5. The method of claim 1 , wherein each stiction-reducing formation comprises a columnar projection on said nozzle plate.
6. The method of claim 5 , wherein each columnar projection projects at least 1 micron from said nozzle plate.
7. The method of claim 5 , wherein each columnar projection is spaced apart from an adjacent columnar projection by less than 2 microns.
8. The method of claim 1 , wherein each stiction-reducing formation comprises an elongate wall projection on said nozzle plate.
9. The method of claim 8 , wherein each wall projection projects at least 1 micron from said nozzle plate.
10. The method of claim 8 , wherein said wall projections are positioned for minimizing color-mixing of inks on said nozzle plate.
11. The method of claim 10 , wherein said wall projections extend along said nozzle plate parallel with rows of nozzles, each nozzle in a row ejecting the same colored ink.
12. The method of claim 1 , wherein the positions of said nozzle rims and said stiction-reducing formations are defined by photolithographic masking.
13. The method of claim 1 , wherein at least half of the surface area of said nozzle plate is tiled with stiction-reducing formations.
14. The method of claim 1 , wherein said inkjet nozzle assemblies are formed on a silicon substrate and said nozzle plate is spaced apart from said substrate.
15. The method of claim 1 , wherein said nozzle plate is comprised of silicon nitride, silicon oxide, silicon oxynitride or aluminium nitride.
16. The method of claim 1 , wherein said nozzle assemblies are sealed by CVD or PECVD deposition of said roof material.
17. The method of claim 16 , wherein said roof material is deposited onto a sacrificial scaffold.
18. The method of claim 1 , wherein each inkjet nozzle assembly has at least one nozzle aperture associated therewith for ejection of ink.
19. The method of claim 1 , wherein said nozzle plate is subsequently treated with a hydrophobizing material.