Resolution limits due to confinement effects in resists

As discussed in Chapter 11, experimental results suggest that material properties of UTR films can differ in significant ways from their bulk counterparts. Of particular interest, because of its influence on the viscoelastic behavior of the spin-coated films, is the effect of film thickness on Eg (see Eig. 17.29), which decreases with film thickness for the particular substrate investigated in the study. 

Despotopoulou, R.D. Miller, J.F. Rabolt, and C.W. Frank, Polymer chain organization and orientation in ultrathin films A spectroscopic investigation, J. Polym. Sci. Pt. B 34, 2335 (1996) L.B. Rothman, Properties of thin pol3dmide films, J. Electrochem. Soc. 127, 2116 (1980). 

Okoroanyanwu, Thin film instabilities and implications for ultrathin resist processes, J. Vac. Sci. Technol. B 18(6), 3381 3387(2000) U. Okoroanyanwu, Limits of ultrathin resist processes, Future Fab Int. 10, 157 163 (2001). 

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