Patent ID: 7527743

Claim:
A method for etching an insulating film, comprising: loading a substrate supporting an insulating film on a supporting bar, the substrate including upper and lower surfaces; spraying etchant onto the upper and lower surfaces of the substrate; and moving the substrate along a lateral direction, wherein moving the substrate includes providing a plurality of rollers in contact with the lower surface of the substrate and rotating the plurality of rollers, the rollers are arranged at the both sides of the supporting bar under the substrate and the rollers at one side of the supporting bar are alternately disposed to the rollers at other side of the supporting bar along the lateral direction so that a plurality of rollers are contacted with the lower surface of the substrate in the zigzag form; and wherein spraying etchant includes spraying the etchant to the contact portions of the substrate contacted with the surface of the plurality of rollers by a surface spray nozzle.