Patent ID: 7560225

Claim:
A method of ion milling comprising the steps of: depositing a photoresist material on a substrate surface in a liquid form; baking the photoresist material prior to an exposing step; exposing the photoresist material through a mask that defines first and second features on the substrate surface to be protected from ion milling, the first and second features being separated by a distance that is greater than a thickness of the photoresist material; developing the photoresist material to remove photoresist material from selected area on the substrate surface between the first and second features while leaving the photoresist material on the first and second features; baking the photoresist material, alter the developing step, on the substrate surface at an elevated temperature for a selected time period; ion milling the selected area on the substrate surface not covered by photoresist material to remove substrate material to a selected etch depth; and removing all photoresist material from the substrate surface.