Abstract: A method for exposing a resist layer with regions of photosensitivity to an image in a lithographic process using a high numerical aperture imaging tool. There is employed a substrate having thereover a layer reflective to the imaging tool radiation and a resist layer having a region of photosensitivity over the reflective layer, with the resist layer having a thickness. The imaging tool is adapted to project radiation containing an aerial image onto the resist layer, with a portion of the radiation containing the aerial image passing through the resist layer and reflecting back to the resist layer. The reflected radiation forms an interference pattern in the resist layer of the projected aerial image through the resist layer thickness.
Type:
Grant
Filed:
November 3, 2005
Date of Patent:
December 30, 2008
Assignee:
International Business Machines Corporation
Inventors:
Kafai Lai, Dirk Pfeiffer, Alan E. Rosenbluth