Contact thermal lithography

Abstract

Contact thermal lithography is a method for fabricating microscale patterns using heat transfer. In contrast to photolithography, where the minimum achievable feature size is proportional to the wavelength of light used in the exposure process, thermal lithography is limited by a thermal diffusion length scale and the geometry of the situation. In this thesis the basic principles of thermal lithography are presented. A traditional chrome-glass photomask is brought into contact with a wafer coated with a thermally sensitive polymer. The mask-wafer combination is flashed briefly with high intensity light, causing the chrome features heat up and conduct heat locally to the polymer, transferring a pattern. Analytic and finite element models are presented to analyze the heating process and select appropriate geometries and heating times. In addition, an experimental version of a contact thermal lithography system has been constructed and tested. Early results from this system are presented, along with plans for future development.