Plasma etching apparatus

1. A method comprising:

providing an apparatus comprising:

a chamber;

a substrate support disposed inside the chamber to support a substrate;

a shield disposed above a center portion of the substrate, with a gap such that plasma is not generated between the shield and the center portion of the substrate, to expose an edge portion thereof, and for preventing plasma from being generated above the center portion of the substrate except at the edge portion;

an antenna disposed at a position on an outer wall of the chamber;

a bias power applying unit;

a curtain gas passageway;

a reaction gas supply passageway; and

a gas injection nozzle;

spraying a curtain gas to a space between the shield and the substrate, using the curtain gas passageway;

spraying a reaction gas to an area between a side surface of the shield and an inner sidewall of the chamber, using the reaction gas supply passageway and the gas injection nozzle which are formed within the shield;

applying plasma-generating power to an area between the edge portion of the substrate and an inner wall of the chamber, using the antenna; and

applying bias to the substrate support, using the bias power applying unit.

2. The method as claimed in claim 1 , wherein the substrate support has a diameter less than that of the substrate to expose a bottom-side region of the edge portion of the substrate.

3. The method as claimed in claim 1 , wherein the substrate support has a same diameter as the shield.

4. The method as claimed in claim 3 , wherein the exposed bottom-side region of the edge portion of the substrate by the substrate support has a width of 1 to 4 mm, and an exposed topside region of the edge portion of the substrate by the shield has a width of 1 to 4 mm.

5. The method as claimed in claim 1 , wherein the substrate support has a diameter less than that of the shield.

6. The method as claimed in claim 1 , wherein the gap between the shield and the center portion of the substrate is in a range of 0.1 to 3 mm.

7. The method as claimed in claim 1 , wherein the shield is formed integrally with or separately from a top wall of the chamber.

8. The method as claimed in claim 1 , wherein the shield is spaced apart from the edge portion of the substrate.

9. The method as claimed in claim 1 , wherein the curtain gas passageway is formed at a center of the shield.

10. The method as claimed in claim 9 , wherein the curtain gas passageway comprises a first curtain gas passageway formed at the center of the shield, a second curtain gas passageway formed at an edge of the shield, and a third curtain gas passageway formed between the first curtain gas passageway and the second curtain gas passageway.

11. The method as claimed in claim 10 , wherein the second and the third curtain gas passageway form concentric circles.

12. The method as claimed in claim 1 , wherein the reaction gas supply passageway is separately formed from the curtain gas passageway.

13. The method as claimed in claim 12 , wherein the gas injection nozzle is formed at a side surface of the shield.

14. The method as claimed in claim 1 , wherein a driving unit is installed below the substrate.

15. The method as claimed in claim 1 , wherein the antenna is disposed in a form of a circular strip or in a spiral form in a region on a top or bottom wall of the chamber between an inner sidewall of the chamber and the shield, or on an outer sidewall of the chamber.

16. The method as claimed in claim 1 , wherein the bias-applying unit and the antenna use a common power source, a first matching circuit is connected between the common power source and the bias-applying unit; and a second matching circuit is connected between the common power source and the antenna.

17. The method as claimed in claim 1 , wherein an insulation material is provided on an inner surface of a wall of the chamber where the antenna is installed.