Abstract

SU-8 is nowadays the photoresist most employed in micromechanics and MEMS applications. The knowledge of the photoacid distribution is essential for maximizing the lithographic processing and for minimizing the critical dimensions of the lithography In this paper we measure the kinetic constant C of the photoacid generation in SU8 negative photoresists using two different methods. The measurements, performed under homogeneous exposures and under holographic exposures at wavelength λ=364 nm, show a good accordance for the kinetic constant values of the photoreaction. The maximal variations of the absorption coefficient and refractive index under using holographic exposures were also measured.

© 2010 Optical Society of America