公开(公告)号：US6064475A

公开(公告)日：2000-05-16

申请号：US329780

申请日：1999-06-10

Applicant: Hung-Chih Chen ,  Yao-Chanet Chu ,  Tzu-Yu Lin ,  Chih-Chien Hung

Inventor： Hung-Chih Chen ,  Yao-Chanet Chu ,  Tzu-Yu Lin ,  Chih-Chien Hung

IPC: G03F7/20 ,  G03F9/00 ,  H01L21/66 ,  G01C1/00

CPC classification number: G03F7/70641 ,  G03F9/7026 ,  H01L22/20 ,  Y10S414/136

Abstract: An apparatus and method for determining local de-focus problems on a real time basis in a wafer exposure system. The distance of a wafer from an objective lens and rotation of the wafer about two orthogonal axis at each field position is adjusted to achieve optimum focus for each field of the wafer. The rotational data is fed to a computer and analyzed to determine if any of the rotational angles or if the difference between individual rotational angle and the mean rotational angle exceed critical angles. If any of the critical angles are exceeded local de-focus will occur and the exposure system must be checked for defects. If none of the critical angles are exceeded processing continues with the next wafer. The comparison of the rotational angles to the critical angles is performed for each wafer before continuing with the next wafer so that problems are discovered on a real time basis.

Abstract translation: 一种用于在晶片曝光系统中实时地确定局部去焦问题的装置和方法。 调整晶片与物镜的距离以及在每个场位置处围绕两个正交轴的晶片的旋转以实现晶片每个场的最佳聚焦。 旋转数据被馈送到计算机并分析以确定是否有任何旋转角度或者如果各个旋转角度与平均旋转角度之间的差异超过临界角度。 如果超过任何临界角，则会发生局部去焦点，并且必须检查曝光系统的缺陷。 如果没有一个临界角超过，则下一个晶片将继续进行。 在继续下一个晶片之前，对每个晶片执行旋转角度与临界角度的比较，从而实时地发现问题。