Polystyrene cross-linking negative resists

Table 3.5. Polystyrene-Based Cross-Linking Negative DUV Resists...

We report here a novel technique used to measure the cross-linking and scission yields for negative acting resist systems. The three systems investigated were polyfglycidyl methacrylate-co-3-chlorostyrene) (GMC), poly(3-chloro-styrene) (PCLS), and polystyrene (PS). The technique requires generating an... 

When some or all of the phenyl rings are substituted with halogen (Scheme 6.11), the radiation sensitivity and the cross-linking efficiency of polystyrene can be enhanced significantly. Negative electron-beam resist formulated from iodi-nated and chlorinated polystyrene and based on this approach have been reported. Sensitivity of about 2 p.C/cm and resolution of about 1-p.m features have been demonstrated with these materials. ... 

A comparative study of polystyrene (PS) with bis(perfluorophenyl) azides 1-2 and the corresponding non-fluorinated bisazides 3-4 as deep-UV resists is reported. Inclusion of as low as 1.2 wt-% of 1 in PS led to 70% retention of thickness after photolysis and development. PS containing 2.4 wt-% of 1 is > 100 times more sensitive as a deep-UV negative resist than PS itself. The presence of 1 in PS also increased the contrast of the resist. On a molar basis, 1 was about 10 times as effective as non-fluorinated bisazide 3 in cross-linking PS while 2 was about 6 times as effective as 4. PS containing 2.4 wt-% of 1 was found to have a deep-UV sensitivity of 5-10 mJ cm and resolution of about 0.5 /tm. 

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