THE MODELING AND SIMULATION OF NONLINEAR PHOTOBLEACHING MATERIALS

Abstract

We found that the Dill's parameters of nonlinearly photobleaching materials of p-diazo-N,N-dimethylaniline chloride zinc chloride(DZC) and poly(di-n-hexylsilane) (PDHS) are irregularly dependent on their film thickness, and also their refractive indexes change during exposure. These difficulties make Dill's model inadequate for the simulation of nonlinear photobleaching materials used in contrast enhanced lithography. A direct approach was proposed to solve these difficulties. Equations with four parameters were derived to simulate the bleaching curves of DZC, PDHS and reported bleaching curve of CEM-2. Equations correlated very well with these curves by using best fitted parameters. Linearity was found with parameters in these equations as a function of film thickness of DZC and PDHS. Based on this linearity, simulations of these nonlinear bleaching curves are more accurate than those using Dill's model.