In this article, the authors present and demonstrate a novel, versatile lithography method with high resolution that they call chemical lithography (ChemLith). The concept is based on the fact that most of the commonly used photoresists change their solubility upon an acid-catalyzed chemical reaction. In photolithography, photoacid generator is mixed in the resist formula and the acid is generated by photon-initiated reactions. Using photons sets the fundamental limit on the feature size for photolithography. To overcome this limit, they propose to physically introduce the catalyzing acid (proton source) to the desired position on the resist surface. This concept can be implemented in two,different ways, using a template in a manner similar to nanoimprint lithography or using an atomic force microscope tip similar to nanoprobe based nanolithography. They have achieved nanoscale feature size in both cases, which confirms the potential of ChemLith as an advanced lithography technique. (c) 2006 American Vacuum Society.