Simulate and optimize optical inspection systems for defect detection using FDTD in combination with Lumerical’s scripting language.
Optimization of optical inspection systems requires studying many illumination and collection modes. There are various parameters that can be adjusted, such as input and output light polarization, illumination and collection numerical apertures, defocusing, etc. In principle, for each configuration of the inspection system, a fully-vectorial simulation of the interaction of light with the analyzed structure is required. Optimization routines are usually composed of many of these simulations; therefore, the process can be very time consuming and demanding in terms of computing resources. By implementing a two-step simulation process, where the light-structure interaction and the optical system simulation are done separately, the optimization process can be done much more efficiently.