Particle scattering field calculation and analysis based on Mie scattering theory

Wafer surface defect detection plays an important role in product yield improvement. Particles are the main source in the majority of defects on wafer. We calculate and analyze the scattering field around the particles on the un-patterned wafer surface by light scattering method. A model was built to calculate an isolated particle based on Mie theory firstly, and another model was built to calculate particle scattering field on a smooth wafer surface based on Bidirectional Reflectance Distribution Function (BRDF). We simulated the scattering field with different parameters set: incidence angle, polarization state and scattering angle channel. The results verify the feasibility of our method to calculate the scattering field.