Simulation of defect detection schemes for wafer inspection in VLSI manufacturing

The detection of critical defects on modern VLSI wafers is a challenging and complex problem. Simulation of these critical defects allows for rapid characterization and optimization of in-line detection schemes. In this paper we introduce a 3D electromagnetic field simulator (METRO 3D) that calculates the scattering of light from wafer topographies. An approach that allows highly absorptive materials to be investigated is discussed for the three dimensional topography simulator. With this enhancement to the simulator, several defect studies were performed and the results of these studies illustrate the ability of the simulator to model wafer topographies and defects that occur in modern fab lines.