Polymer Chain Structure in Ultrathin Films

摘要

As the dimensions of integrated circuits have been shrinking, the desired resolution will soon be beyond the limit of conventional ultraviolet (UV) lithography. Deep UV and X-radiation, high energy electron beams and low energy scanning tunneling microscopy (STM) have been proposed as possible exposure systems for the next generation high resolution lithography. In order to enhance efforts for the improvement of new exposure systems, appropriate resist materials, preparation methods and processing parameters become the key factors. In optical lithography the resolution is limited by resist absorption, light diffraction, and rheological effects related to the resist development process. In electron beam lithography, the major limitation on the resolution is imposed by electron scattering (proximity effect) which causes a nonuniform incident exposure in the pattern area. (jes)