PLASMA-DEPOSITED ORGANOSILICON THIN-FILMS AS DRY RESISTS FOR DEEP ULTRAVIOLET LITHOGRAPHY

Organosilicon thin films have been formed by plasma enhanced chemical vapor deposition and employed as deep-UV photoresists. Films 20-200 nm thick were deposited from liquid organosilicon sources onto carbon-based planarizing layers and patterned in projection with a 193 nm excimer laser. At fluences below approximately-5 mJ/cm2/pulse, exposure to 193 nm radiation induced oxygen incorporation into the film. Following either a wet or dry development step, negative-tone imaging was achieved, with the remaining photooxidized film being highly resistant to the O2 reactive ion etching employed in the subsequent pattern transfer step. At higher fluences, approximately-15 mJ/cm2, positive-tone imaging by self-development was obtained for single-pulse exposures.