A High-Speed ​​Review Method for Microscopic Defects

Abstract

The invention discloses a high-speed micro-defect review method, which comprises the following steps: A) image scanning to find the position of the defect point; B) the automatic focus of the camera is always on, and the camera moves at a constant speed along the curve formed by the defect points; C) reaching each a defect point, trigger the camera and the flash, and complete the image capture of the defect point. The method of taking pictures for the review is to pass through each defect point at a constant speed, and the automatic focus is always on. When the camera lens approaches the next defect point, the camera and flash light are triggered, and there is no pause or vibration when reaching each defect point; The vibration caused by the change of the direction of motion between the sensors settles down before the sensor reaches the position of the defect point, so the time of the entire review process is shortened, and the efficiency of the review and image acquisition is high.

Description

technical field [0001] The invention relates to the technical field of optical detection, in particular to a high-speed micro-defect review method. Background technique [0002] An effective AOI (automatic optical inspection) system generally consists of two parts: 1) fast low-magnification image scanning to find the location of product surface defects; 2) review with high-magnification microscopic images to determine the nature of the defect and types. [0003] The usual review process is to first obtain the x / y coordinates of multiple defect points, calculate the optimal path, and then review and take pictures point by point. Going from one point to the next is to move in a straight line, first accelerate, then decelerate, stop when it reaches the next defect point, perform autofocus, and then take a picture. One problem with this process is that rapid deceleration can cause vibrations in the motion system, which can cause autofocus instability. Existing solutions are t...

AI Technical Summary

Problems solved by technology

[0004] like figure 1 As shown, assume that points P1, P2, P3, P4, P5, and P6 are defect points of the wafer. In the traditional process, a straight line scan from P1 to P2 is performed. In the process of P2, the process of accelerating first and then decelerating makes the sensor vibrate and the focus is unstable

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