Patent ID: 8076055

Claim:
A method of patterning a semiconductor device, the method comprising: forming a photoresist material over a semiconductor wafer; imaging a light source using a lithographic mirror of a reflective lithographic system to expose the photoresist material through a mask, the lithographic mirror comprising: a first substrate formed of a low-thermal expansion material (LTEM); a first multi-layer reflector of alternating layers of molybdenum and silicon formed on the first substrate; and a first capping layer formed in direct contact onto the first multi-layer reflector, the first capping layer comprising a single layer of an oxide that is chemically inert in an oxidizing environment, said layer of oxide selected from the group consisting of HfO 2 , Y 2 O 3 -stabilized ZrO 2 , and combinations thereof; removing a portion of the photoresist material corresponding to the portion that was exposed or a portion that was not exposed; and modifying the semiconductor wafer where the photoresist material was removed.