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The capability of SEMATECH's Lasertec M7360 inspection tool to detect particles of different sizes and composition was studied on the surface of fused silica and MoSi multilayers (MLs) with a Si cap layer. Particles of Au, Ag, SnO2, Fe2O3, and Al2O3 were deposited and inspected 10 times with the M7360. Tool pixel size histograms were used to calculate the average pixel size per particle category. The calibration curves of pixel size for polystyrene latex (PSL) spheres were used to convert the average pixel size to the optical size of the defects as detected by the M7360. Selective sets of each category of particles then were reviewed by atomic force microscope (AFM) to calculate the sphere equivalent volume diameter (SEVD) of the particles. The contribution of the surface on which particles were deposited and defect composition and shape were studied. Our results indicate that for Fe2 O3 and SnO particles, size distribution on the surface of fused silica and MLs is similar and no effect of the substrate was observed. The AFM-measured SEVD size of particles were close to the nominal size of particles specified by the particle supplier. Optical size of particles were found to be larger or smaller than SEVD size for the different particles. In the case of the Au particles, the PSL equivalent optical size was found to be larger than the SEVD in good agreement with the modeling. By using prefabricated rectangular defects on a fused silica surface, we showed that the M7360 differentiates between the PSL and SEVD size of prefabricated defects. The PSL size is smaller than the SEVD size of prefabricated defects for particle sizes below 100 nm.
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