Etchant and method for fabricating liquid crystal display using the same
View Patent ↗Provided are an etchant used for a transparent conductive oxide layer and a method for fabricating a liquid crystal display (LCD) using the etchant. The etchant includes 2-5 wt % sulfuric acid, 0.02-10 wt % hydrogen sulfate of alkali metal, and deionized water as the remainder.
1. An etchant for a transparent conductive oxide layer comprising:
2-15 wt % sulfuric acid;
0.02-10 wt % hydrogen sulfate of an alkali metal; and deionized water as the remainder,
wherein the transparent conductive oxide layer is made of indium tin oxide (ITO) or indium zinc oxide (IZO).
2. The etchant of claim 1 , wherein the hydrogen sulfate of an alkali metal includes KHSO 4 .
3. The etchant of claim 2 , further comprising a 0.02-10 wt % auxiliary oxidizer.
4. The etchant of claim 3 , wherein the auxiliary oxidizer is a compound of at least one selected from the group consisting of H 3 PO 4 , HNO 3 , CH 3 COOH, HClO 4 , H 2 O 2 , and oxone.
5. The etchant of claim 1 , wherein the hydrogen sulfate of an alkali metal includes KHSO 4 , further comprising a 0.02-10 wt % auxiliary oxidizer, further comprising a 0.01-5 wt % auxiliary inhibitor.
6. The etchant of claim 5 , wherein the auxiliary oxidizer is a compound of at least one selected from a group consisting of H 3 PO 4 , HNO 3 , CH 3 COOH, HClO 4 , H 2 O 2 , and oxone.
7. The etchant of claim 5 , wherein the auxiliary inhibitor is a compound of at least one selected from the group consisting of CH 3 COONH 4 , NH 4 SO 3 NH 2 , NH 4 C 6 H 5 O 2 , NH 4 COONH 4 , NH 4 Cl, NH 4 H 2 PO 4 , NH 4 OOCH, NH 4 HCO 3 , H 4 NO 2 CCH 2 C(OH)(CO 2 NH 4 )CH 2 CO 2 NH 4 , NH 4 PF 6 , HOC(CO 2 H)(CH 2 CO 2 NH 4 ) 2 , NH 4 NO 3 , (NH 4 ) 2 S 2 O 8 , H 2 NSO 3 NH 4 , and (NH 4 ) 2 SO 4 .
8. The etchant of claim 1 , wherein the hydrogen sulphate of an alkali metal includes KHSO 4 , further comprising 0.01-5 wt % auxiliary inhibitor.
9. The etchant of claim 8 , wherein the auxiliary inhibitor is a compound of at least one selected from the group consisting of CH 3 COONH 4 , NH 4 SO 3 NH 2 , NH 4 C 6 H 5 O 2 , NH 4 COONH 4 , NH 4 Cl, NH 4 H 2 PO 4 , NH 4 OOCH, NH 4 HCO 3 , H 4 NO 2 CCH 2 C(OH)(CO 2 NH 4 )CH 2 CO 2 NH 4 , NH 4 PF 6 , HOC(CO 2 H)(CH 2 CO 2 NH 4 ) 2 , NH 4 NO 3 , (NH 4 ) 2 S 2 O 8 , H 2 NSO 3 NH 4 , and (NH 4 ) 2 SO 4 .
10. The etchant of claim 1 , further comprising a 0.02-10 wt % auxiliary oxidizer.
11. The etchant of claim 10 , wherein the auxiliary oxidizer is a compound of at least one selected from the group consisting of H 3 PO 4 , HNO 3 , CH 3 COOH, HClO 4 , H 2 O 2 , and oxone.
12. The etchant of claim 1 , further comprising a 0.02-10 wt % auxiliary oxidizer, further comprising a 0.01-5 wt % auxiliary inhibitor.
13. The etchant of claim 12 , wherein the auxiliary oxidizer is a compound of at least one selected from the group consisting of H 3 PO 4 , HNO 3 , CH 3 COOH, HClO 4 , H 2 O 2 , and oxone.
14. The etchant of claim 12 , wherein the auxiliary inhibitor is a compound of at least one selected form the group consisting of CH 3 COONH 4 , NH 4 SO 3 NH 2 , NH 4 C 6 H 5 O 2 , NH 4 COONH 4 , NH 4 Cl, NH 4 H 2 PO 4 , NH 4 OOCH, NH 4 HCO 3 , H 4 NO 2 CCH 2 C(OH)(CO 2 NH 4 )CH 2 CO 2 NH 4 , NH 4 PF 6 , HOC(CO 2 H)(CH 2 CO 2 NH 4 ) 2 , NH 4 NO 3 , (NH 4 ) 2 S 2 O 8 , H 2 NSO 3 NH 4 , and (NH 4 ) 2 SO 4 .
15. The etchant of claim 1 , further comprising a 0.01-5 wt % auxiliary inhibitor.
16. The etchant of claim 15 , wherein the auxiliary inhibitor is a compound of at least one selected from the group consisting of CH 3 COONH 4 , NH 4 SO 3 NH 2 , NH 4 C 6 H 5 O 2 , NH 4 COONH 4 , NH 4 Cl, NH 4 H 2 PO 4 , NH 4 OOCH, NH 4 HCO 3 , H 4 NO 2 CCH 2 C(OH)(CO 2 NH 4 )CH 2 CO 2 NH 4 , NH 4 PF 6 , HOC(CO 2 H)(CH 2 CO 2 NH 4 ) 2 , NH 4 NO 3 , (NH 4 ) 2 S 2 O 8 , H 2 NSO 3 NH 4 , and (NH 4 ) 2 SO 4 .
17. The etchant of claim 1 , wherein the indium tin oxide (ITO) is amorphous indium tin oxide (ITO).
18. An etchant for a transparent conductive oxide layer, comprising:
2-15 wt % sulfuric acid;
0.02-10 wt % hydrogen sulfate of alkali metal;
a 0.02-10 wt % auxiliary oxidizer;
a 0.01-5 wt % auxiliary inhibitor; and
deionized water as the remainder,
wherein the transparent conductive oxide layer is made of indium tin oxide (ITO) or indium zinc oxide (IZO).
19. The etchant of claim 18 , wherein hydrogen sulfate of alkali metal includes KHSO 4 .
20. The etchant of claim 18 , wherein the auxiliary oxidizer is a compound of at least one selected from the group consisting of H 3 PO 4 , HNO 3 , CH 3 COOH, HClO 4 , H 2 O 2 , and oxone.
21. The etchant of claim 18 , wherein the auxiliary inhibitor is a compound of at least one selected from the group consisting of CH 3 COONH 4 , NH 4 SO 3 NH 2 , NH 4 C 6 H 5 O 2 , NH 4 COONH 4 , NH 4 Cl, NH 4 H 2 PO 4 , NH 4 OOCH, NH 4 HCO 3 , H 4 NO 2 CCH 2 C(OH)(CO 2 NH 4 )CH 2 CO 2 NH 4 , NH 4 PF 6 , HOC(CO 2 H)(CH 2 CO 2 NH 4 ) 2 , NH 4 NO 3 , (NH 4 ) 2 S 2 O 8 , H 2 NSO 3 NH 4 , and (NH 4 ) 2 SO 4 .
22. The etchant of claim 18 , wherein the indium tin oxide (ITO) is amorphous indium tin oxide (ITO).
23. A method for fabricating a liquid crystal display (LCD), the method comprising:
providing an insulating substrate in which a transparent conductive oxide layer is formed; and
patterning the transparent conductive oxide layer by etching the transparent conductive oxide layer using the etchant of one of claims 1 to 14 .
24. The method of claim 23 , wherein the etching is performed at 30-50° C.
25. The method of claim 23 , wherein the etching is performed for 20-100 seconds.
26. The method of claim 23 , wherein the transparent conductive oxide layer is made of indium tin oxide (ITO) or indium zinc oxide (IZO).
27. The method of claim 26 , wherein the indium tin oxide (ITO) is amorphous indium tin oxide (ITO).