Resist process development for sub-100-nm ion projection lithography

Ion projection lithography (IPL) is designed to realize resist structures o n the wafer plane well below 100 nm. Patterns from a stencilmask are printe d with 4 X reduction using an electrostatic lens system. First exposures wi th the IPL Process Development Tool [Proc. SPIE 3997 (2000)] will start wit hin the fourth quarter of this year. In the meantime, a baseline resist pro cess for i-line, DUV and e-beam resists has been established with exposures on a 1 X masked ion beam lithography (MIBL) tool at IMS-Vienna. The result s as obtained with 75-keV He+ ions are compared with experiments using a 30 -keV e-beam writer at IMS-Chips, Stuttgart. Resists were provided by Shiple y and Clariant. For the first time, through close interaction with industri al resist companies, ion beam resist materials are available and characteri zed with well tailored sensitivities in order to vary the IPL exposure dose between 0.4 and 3 muC/cm(2) (double the dose to clear large areas value). These materials will be essential to study and establish the required IPL r esist exposure dose for sub-100-mn structures. We measured the sensitivitie s (dose to clear large areas), contrast curves as well as MIBL dose latitud es. With higher precision than previously done [J. Vac. Sci. Technol. B 15 (1997) 2355] the contrast curves have to be established as input data for I PL simulations. The IPL sensitivity is lower by more than an order of magni tude, compared to 30-keV e-beam exposure. Our paper presents and discusses the results. For IPL resist simulations the Monte Carlo simulator SRIM 2000 [Ziegler et al., The Stopping and Ranges of Ions in Solids, Pergamon, New York (1985)] is used to obtain energy density distributions in CxHyOz resis t materials. We are presenting and comparing point spread functions of 60 a nd 75 keV H+ ions, He+ ions and electrons. (C) 2001 Published by Elsevier S cience BY.