Effects of resin and inhibitor structure on dissolution rate

7 Effects of resin and inhibitor structure on dissolution rate 

There is ample evidence that the structural properties of phenolic resins such as novolac and poly (hydroxy styrene), as well as the inhibitors associated with them, do exert considerable influence on the dissolution properties of the DNQ/ novolac resist.  

Hanabata, Y. Uetani, and A. Furuta, Novolak design for high resolution positive photoresists. II. stone wall model for positive photoresist development, Proc. SPIE 920, 349 482 (1990). C.G. Willson, R. Miller, D. McKean, N. Clecak, T. Tompkins, D. Hofer, J. Michl, and J. Downing, Design of a positive resist for projection lithography in the mid UV, Polym. Sci. Eng. 23, 1004 (1983) M.K. Templeton, C.R. Szamanda, and A. Zampini, Dissolution kinetics of positive photo resists the secondary structure model, Proc. SPIE 771, 136 (1987). 

As discussed earlier in the secondary structure model, Templeton et al. have shown that the steric arrangement of the methylene links in the novolac resin can have a profound effect on its dissolution rate and on lithographic performance. Using molecular mechanics, these authors have calculated the equilibrium secondary structures of cresol-formaldehyde oligomers. They found that the secondary structure of these molecules determines the relative positions of the hydroxyl groups in the novolac matrix, and hence the possibility of intramolecular hydrogen bonding.  

Templeton, C.R. Szamanda, and A. Zampini, Dissolution kinetics of positive photoresists the secondary structure model, Proc. SPIE 771, 136 (1987). 

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