Patent ID: 6309806
Filing Date: 2001-10-30
Classification: G03F

Abstract:
A method of providing the inside surface of a metal liner for an engine cylinder with at least one oil retaining microscopic feature having a desired depth less than a thickness of the metal liner, including the steps of coating at least a part of the inside surface with photo-sensitive material, directing light onto the material to photo-expose a selected portion of the material, removing the exposed selected portion or the unexposed material thereby to leave an opening through the coating, applying an etching substance to etch the inside surface through the opening to form the microscopic feature in the inside surface having the desired depth between about 3 .mu.m and about 15 .mu.m, wherein the light which is directed onto the photo-sensitive material comprises a collimated beam and during exposure the beam and the inside surface are relatively moved so that the beam impinges upon the selected portion of the photo-sensitive coating to be exposed.