Deep-UV (240-250 nm) lithography is of one the most promising new lithographic techniques for patterning devices with 0.35-0.5 μm structures. Chemically amplified resists have been reported to meet the necessary requirements of both excimer laser and Hg source-based exposure tools. The chemistry of one family of these materials involves the photogeneration of organic acid catalysts from 2,6-dinitrobenzyl esters, which, upon mild heating, effect the removal of a t-butoxy carbonyl protecting group from poly(t-butoxycarbonyloxy-α-methylstyrene), [poly(t-BOC-α-methylstyrene)]. The thermal behavior of the esters has been examined, and the quantum yield determined for selected examples. A lithographic evaluation of resists based upon several organic ester acid precursors and poly(t-BOC-α-methylstyrene) has been made. Sensitivities ranging from 2 to 100 mJ/cm² in the deep-UV region have been observed, and 0.5 μm resolution has been demonstrated, using a contact printer equipped with a 248 nm laser source.

Date Published: 30 January 1989
PDF: 9 pages
Proc. SPIE 1086, Advances in Resist Technology and Processing VI, (30 January 1989); doi: 10.1117/12.953012

Published in SPIE Proceedings Vol. 1086:
Advances in Resist Technology and Processing VI
Elsa Reichmanis, Editor(s)