激光位移传感器在晶圆检测中的应用研究

Application Research of Laser Displacement Sensor in Wafer Inspection

由于极高的光学分辨要求,导致焦深日益减小,为适应十分有限的焦深,探索一种可以应用于晶圆检测设备中的调焦技术。主要研究内容包括激光位移传感器检焦测量原理、调焦工作原理、调焦流程以及利用最小二乘法拟合晶圆面型。采用Tenengrad梯度函数和Sobel算子提取像素点水平方向和垂直方向的梯度值,以此来评判图像清晰度,验证激光位移传感器在晶圆检测工作中调焦得可行性,从而提供一种更加通用便捷的工程解决方案。

Due to extremely high optical resolution requirements,the depth of focus is increasingly reduced.The goal of this subject is to explore a focusing technology that can be applied to wafer inspection equipment.The main research content includes focusing measurement principle,focusing working principle,focusing process,and the use of least squares to fit the wafer surface.In this paper,the Tenengrad gradient function and Sobel operator are used to extract the horizontal and vertical gradient values of the pixel points to judge the image clarity and verify the feasibility of using the laser displacement sensor to focus in wafer inspection.So as to provide a more general and convenient engineering solution.