Nozzle plate manufacturing method, nozzle plate, droplet discharge head manufacturing method, droplet discharge head, and printer
A nozzle plate manufacturing method that offers excellent protection against discharge liquid and that enables a nozzle plate having high nozzle-hole accuracy to be manufactured with good yield. The invention also provides a nozzle plate, a droplet discharge head manufacturing method, and a droplet discharge head.
1. A method for manufacturing a plate, the method comprising:
forming a first etching mask on a first surface of a silicon substrate;
forming a first depression in the first surface of the silicon substrate by a first etching;
removing the first etching mask;
forming a first liquid-resistant protective film on the silicon substrate, the first liquid-resistant protective film having liquid resistance;
bonding a support substrate to the first surface of the silicon substrate, the support substrate supporting the silicon substrate;
reducing the silicon substrate to a desired thickness from a second surface side opposite to the first surface;
forming a second etching mask on the second surface of the silicon substrate;
forming a second depression in the second surface of the silicon substrate by a second etching; and
detaching the support substrate from the silicon substrate.
2. The method according to claim 1 , further comprising:
forming a liquid repellent layer on the first liquid-resistant protective film, the liquid repellent layer having liquid repellency, and
removing a part of the first liquid-resistant protective film and a part of the liquid repellent layer.
3. The method according to claim 2 , further comprising:
forming a second liquid-resistant protective film on the silicon substrate, the second liquid-resistant protective film having liquid resistance.
4. The method according to claim 1 , wherein
a thickness of the silicon substrate is reduced by grinding.
5. The method according to claim 1 , wherein
the first depression and the second depression are formed by dry etching.
6. The method according to claim 1 , wherein
the second depression is formed by isotropic dry etching.
7. The method according to claim 1 , wherein
the second depression is formed by anisotropic dry etching.
8. The method according to claim 1 , wherein
an open area of the second depression is larger than an open area of the first depression.
9. The method according to claim 1 , wherein
a cross sectional area of the second depression parallel to the first surface gradually increases from the first surface toward the second surface.
10. The method according to claim 1 , wherein
the first liquid-resistant protective film is a thermal oxidation film.
11. A method for manufacturing a nozzle plate, the method comprising:
forming the nozzle plate by using the method according to claim 1 .
12. A method for manufacturing a droplet discharge head, which includes a nozzle plate that has a plurality of nozzle holes from which a liquid is discharged, a cavity substrate that has a plurality of cavities in which the liquid is contained, and a pressure generator that discharges the liquid to the cavities, the method comprising:
forming the nozzle plate by using the method according to claim 1 .
13. A method for manufacturing a plate, the method comprising:
forming a first etching mask on a first surface of a silicon substrate;
forming a first depression in the first surface of the silicon substrate by a first etching;
removing the first etching mask;
forming a first liquid-resistant protective film on the silicon substrate, the first liquid-resistant protective film having liquid resistance;
reducing the silicon substrate to a desired thickness from a second surface side opposite to the first surface;
forming a second etching mask on the second surface of the silicon substrate;
forming a second depression in the second surface of the silicon substrate by a second etching; and
removing the first liquid-resistant protective film.
14. The method according to claim 13 , further comprising:
forming a second liquid-resistant protective film on the silicon substrate, the second liquid-resistant protective film having liquid resistance.
15. The method according to claim 14 , further comprising:
forming a liquid repellent layer on the silicon substrate, the liquid repellent layer having liquid repellency.
16. The method according to claim 13 , further comprising:
forming a liquid repellent layer on the silicon substrate, the liquid repellent layer having liquid repellency.
17. The method according to claim 13 , wherein
when the first liquid-resistant protective film is removed, an area that includes the second depression is removed.
18. The method according to claim 13 , wherein
when the first liquid-resistant protective film is removed, an outer circumference of the silicon substrate is not removed.
19. The method according to claim 13 , wherein
a thickness of the silicon substrate is reduced by grinding.
20. The method according to claim 13 , wherein
the first depression and second depression are formed by dry etching.
21. The method according to claim 13 , wherein
the second depression is formed by isotropic dry etching.
22. The method according to claim 13 , wherein
the second depression is formed by anisotropic dry etching.
23. The method according to claim 13 , wherein
an open area of the second depression is larger than an open area of the first depression.
24. The method according to claim 13 , wherein
a cross sectional area of the second depression parallel to the first surface gradually increases from the first surface toward the second surface.
25. The method according to claim 13 , wherein
the first liquid-resistant protective film is a thermal oxidation film.
26. A method for manufacturing a nozzle plate, the method comprising:
forming the nozzle plate by using the method according to claim 13 .
27. A method for manufacturing a droplet discharge head, which includes a nozzle plate that has a plurality of nozzle holes from which a liquid is discharged, a cavity substrate that has a plurality of cavities in which the liquid is contained, and a pressure generator that discharges the liquid to the cavities, the method comprising:
forming the nozzle plate by using the method according to claim 13 .