Patent ID: 8728338

Claim:
An etching method using an etching apparatus, wherein the etching apparatus comprises: a rotatable stage where an object to be etched is placed; and four arms comprising an etchant supply nozzle for supplying etchant to a surface to be etched on the object; wherein the four arms can be positioned in a direction substantially from a center of the stage toward a peripheral portion with an angle difference of about 90°; and wherein the etching method comprises: supplying the etchant to a first position nearest to the center of the object which is rotating, from a first etchant supply nozzle placed on a first arm; supplying the etchant to a second position second nearest to the center of the object, from a second etchant supply nozzle placed on a second arm, wherein the second arm is substantially symmetrically positioned with respect to the first arm and the second arm has an angle difference of about 180° with respect to the first arm; supplying the etchant to a third position on the object from a third etchant supply nozzle placed on a third arm, wherein the third arm is positioned between the first arm and the second arm; supplying the etchant to a fourth position of the object from a fourth etchant supply nozzle placed on a fourth arm, wherein the fourth arm is substantially symmetrically positioned with respect to the third arm; supplying the etchant to a fifth position of the object from a fifth etchant supply nozzle placed on the second arm; supplying the etchant to a sixth position of the object from a sixth etchant supply nozzle placed on the first arm.