Research And Implementation Of The System Structure Of A Lithography Simulation Tool In VDSM

VDSM (Very Deep Sub-micron) era has come in IC design and manufacture field. Beginning from 0.18um technology node, Sub-wavelength Lithography is widely used in semiconductor manufacture process. When the IC character size is very close to the limitation of exposure system in theory, the real shapes created on the wafer will not be consistent with the layout, which is called OPE (Optical Proximity Effect). The distortion in pattern transferring process may influence functionality and performance of IC products and lower the production yield. RET (Resolution Enhancement Technology) are now widely used in Sub-wavelength Lithography circumstance to solve some manufacturability problems.RET needs support of corresponding EDA software. RET has two ways to modify the layout. One is OPC (Optical Proximity Effect), the other is PSM (Phase Shifting Mask). Both of the two methods need a tool to simulate the image on the wafer under real lithography situations. This thesis focuses on the study of lithography process simulation.To build the source model, mask model and optical project model of lithographic system, we have studied the IC manufacture process, analyzed lithographic machine structure and the imaging theory. Based on the research of the lithography simulation system structure and summerizing of the tools present, we develop a lithography simulation tool which has powerful math library and supports all lithography system units. The script language enviorment has good development extensions. What's more, we have implemented a lithography simulation development tool, Litholab, which can help the researchers on lithography simulation.