Fast imaging algorithm for simulation pattern transfer in deep-UV resis and extracting post exposure bake parameters

摘要

This paper presents a simulator, RIAR (Rapid Imaging Analysis for Resists), for fast imaging resist profiles given a post exposure bake (PEB) model. First, the aerial image profile on the surface of the resist is obtained through SPLAT> Then the image profile is converted into the resist pattern after PEB and develop by solving a given 2-dimemsional PEB model, which is usually a 2-D partial differential equation (PDE) system. The 2-D PDE system is taken as an image tranform and is solved by iteratively approximating the solution with 3-Variable polynomial on space and is much faster than the traditional PDE solver. The time complexity of RIAR and STORM are compared with respect to reaction rate, diffusivity, simulation scale, etc. RIAR achieves a speed up of 5 to 7 times STORM, maintaining the precision. In addition, RIAR consumes much less memory and can simulate domains of 9,000 nodes on a DEC Alpa 600MHz, 256MB DRAM workstation in a reasonable time. An example of applying RIAR in line-end shortening simulation is also given.