ETCH RESISTANCE ENHANCEMENT AND ABSORBENCY OPTIMIZATION WITH POLYAROMATIC COMPOUNDS FOR THE DESIGN OF 193 NM PHOTORESISTS

The O-2 and SF6 plasma etch rate reduction of poly methyl methacrylate films provided by a series of adamantane and anthracene derivatives a t different loadings was examined. The improvement is substantial at l oadings up to 10 % but further reduction by increasing loading is not easily achieved. Anthracenes have distinctly better performance especi ally with SF, plasmas. Spectral characteristics of anthracene compound s at the 193 nm legion allow loadings of 5-10% to produce single layer model resists. The loadings amount depends on the specific compound u sed and the spectrum of the base polymer. Good sensitivities for 193nm imaging have been obtained only with acrylate/anthracene formulations based on the concept of chemical amplification with onium salts.