Inventors:
Paul Stephen Andry - Mohegan Lake NY
Evan George Colgan - Chestnut Ridge NY
Hisanori Kinoshita - Kusatsu, JP
Hiroaki Kitahara - Ohtsu, JP
Frank R. Libsch - White Plains NY
Kai R. Schleupen - Yorktown Heights NY
Assignee:
International Business Machines Corporation - Armonk NY
International Classification:
H01L 2100
US Classification:
438158, 438151, 438159, 438160
Abstract:
A method for opening resist in raised areas of a semiconductor device. In one aspect, a conductive layer is formed over a channel insulator layer to form a raised portion including a height above a substantially planar surrounding area, the channel insulator layer being aligned to a gate electrode. A photoresist layer is formed over the raised portion and the surrounding area, and patterned by employing a gray scale light mask to reduce exposure light on the photoresist over the raised portion. Then, the photoresist is etched to thin it such that a gap is formed in the photoresist down to the conductive layer over the raised portion, but the photoresist remains everywhere else, and the conductive layer is etched in accordance with the photoresist to form source and drain electrodes which are self aligned to the channel insulator layer.