Chinese Academy of Sciences

Jinhua Feng

Yi Li

Yu He

Xiangang Luo

Song Hu

Lixin Zhao

Jian Wang

Wei Yan

Shaoyu Zhang

Hongyu Shao

Sihan Wu

Yanli Li

Provided are illumination field non-uniformity detection system, detection method, correction method, and device provided. The system includes displacement control module, controlling displacement platform to drive photodetector and image sensor to move within illumination field; illumination signal acquisition module, controlling the photodetector to collect different response signals at various collecting frequencies within the illumination field and controlling the image sensor to collect response images within the illumination field; data processing module, obtaining, based on different response signals, multiple illumination fields with different light radiation intensities and light intensity distribution considered to be uniform; based on this, obtaining multiple corrected image sensor grayscale matrices; fitting the multiple corrected image sensor grayscale matrices to obtain parameter matrix; and non-uniformity detection module, correcting the response images based on the parameter matrix; and characterizing non-uniformity of light intensity distribution within the illumination field using non-uniform metrics of grayscale distribution of the corrected response images.

Illumination field non-uniformity detection system, detection method, correction method, and device

The present disclosure provides a high accuracy measurement system for focusing and leveling. The system determines an off-focus distance in the perpendicular direction within the exposure field and an inclination in the horizontal direction by measuring heights of four detection points on a substrate by using a four-channel detection method, thereby achieving focusing and leveling of the substrate. The detection of the substrate heights is implemented by a focusing method based on dual-channel light intensity modulation. Two superposed grating fringes are formed with phase difference of &#x3c0;/2. The shift can be resolved by the phase variation of corresponding fringes. According to the method, the off-focus distance can be derived. The present disclosure effectively eliminates the error due to the intensity changes caused by the fluctuations of the source or the reflectance of the substrate surface. The apparatus for focusing and leveling is easy to be implemented and has an accuracy of nanoscale.

High accuracy measurement system for focusing and leveling

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Sichuan, China

Jinhua Feng