Detection system and method based on optical dark field microscopy

Abstract

The invention relates to the field of defect detection and nanoparticle detection, and provides a detection system and method based on an optical dark field microscopy. According to the present invention, by using the difference between the surface fluctuation of the sample and the spatial distribution and the geometrical morphology of the detection target, the illumination light beam in the specific polarization state is irradiated to the to-be-detected region of the sample at the certain angle so as to reduce the stray light intensity of the nano-scale or sub-nano-scale fluctuation scattering on the surface of the sample; the polarization of the signal light scattered by the stray light and the detection target is different, the polarization state of the detection light beam is regulated and controlled, most stray light is filtered out, background noise caused by the stray light is reduced, the detection signal-to-noise ratio is increased, and the detection sensitivity is improved. By using the system and the method disclosed by the invention, defects and nanoparticles which can be detected by an optical method can be greatly pushed to smaller sizes.

Description

technical field [0001] The present invention relates to the field of defect detection and nanoparticle technology, in particular to a detection system and method based on dark-field microscopy technology, which selects the polarization state of the light-frequency electric field and the incident angle of the illumination beam, and regulates the polarization state of the light-frequency electric field of the detection beam , A system and method for enhancing the detection signal-to-noise ratio. Background technique [0002] Defect detection usually refers to the detection of defects on the sample surface, including but not limited to foreign pollutants, abnormal protrusions on the sample surface, scratches on the sample surface, grooves on the sample surface, deformation of specific pattern structures on the sample surface, etc. Defect detection has a large demand in various industrial productions, such as integrated circuits, display panels, glass and metal products and othe...

AI Technical Summary

Problems solved by technology

When the detection target is smaller than a certain size, the stray light intensity will be close to or even greater than the signal light intensity, causing the detection signal to be overwhelmed by background noise

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