Lithography Materials - The chemistry and scanning electron micrographs of nanoscale images of a "low-blur" CA resist


A practical demonstration of this is presented in the figure below. The resist chemistry illustrated there has the unusual property that the acid catalyzed deprotection chemistry (a hydrolysis in this case) occurs in minutes at room temperature, compared to a typical post-exposure bake requiring a temperature of 100 degrees C or more. Since, at room temperature, the rate of diffusion will be lowered, the deprotection/diffusion rate ratio is this system is significantly increased compared to more conventional systems. In practice, this resist chemistry has been experimentally measured1 to have a image blur only one-third that of conventional CA resists. Images of this resist exposed using electron-beam nanolithography2 are evidence that this resist chemistry is capable of resolving features to at least the 30 nm dimensional scale.

The chemistry (top) and scanning electron micrographs of nanoscale images (bottom) of a 'low-blur' CA resist.

 References

  1. J.P. Cain, P.P. Naulleau, E.M. Gullikson, C.J. Spanos, J. Vac. Sci. Techn. B, 24, 1234-1237, (2006)
  2. G. M. Wallraff, D. R. Medeiros, J. Bucchino, K. Petrillo, C. Rettner, Martha Sanchez, W. Hinsberg, F. Houle, D. Goldfarb, Karen Temple, C. E. Larson, B. Davis, L. Sundberg, P. Brock, J. A. Hoffnagle, S. Wind and Wu-Song Huang, J. Vac. Sci. Technol. B, 22, 3479-3484 (2004)