Abstract
This paper describes silylation and dry development research on 193nm NTS4 and 248nm PlasmaskTM 305u resists. In the first section we performed a statistically designed set of experiments on 248nm exposed PlasmaskTM 305U resist, silylated with TMDS and dry developed with an O2/SO2 plasma. The effects of some of the important dry development parameters such as TCP power, Bias power and SO2 and O2 gas flows on etch rate, uniformity, etch anisotropy, profile, line edge roughness (LER) and several lithographic parameters are described and quantified. Trends for the effects of temperature and pressure are also presented. In a second set of experiments these Plasmask/TMDS trends are applied to the process optimization for 0.12 and 0.13μm lines and spaces on NTS4 resist exposed with 193nm radiation and silylated with DMSDMA. The effects of a plasma bake step and an improved breakthrough step on the LER of the NTS4 process are also demonstrated for sub-0.15μm structures. In both sets of experiments the silylation and the dry development are carried out in a cluster tool consisting of a silylation prototype module and a Lam TCPTM 9400SE Alliance etcher. The resulting features of an optimized dry development process are presented in Figure 14.
