公开(公告)号：WO03058681A3

公开(公告)日：2003-08-28

申请号：PCT/US0241364

申请日：2002-12-24

Applicant: KLA TENCOR CORP

Inventor： KRANTZ MATTHIAS C ,  PETTIBONE DONALD W ,  KVAMME DAMON F ,  STOKOWSKI STAN

IPC: G01N21/896 ,  G01N21/956 ,  G03F1/84 ,  G03F7/20 ,  H01L21/027 ,  G01B9/02

CPC classification number: G01N21/95607 ,  G01N2021/95676 ,  G03F1/84

Abstract: Provided are apparatus and methods for detecting phase defects. The invention relies generally on the distortion of light as it passes through defects in phase shift masks (310) to detect these defects. Light traveling through a defect, such as a bump in an etched area will travel at a different rate than light traveling through air. In order to enhance the signals generated from the defects, the invention in several embodiments provides a defocused light beam (302) by setting the focus of the beam to a level above or below the photomask subject to inspection. The light from the photomask is collected by a detector (314) that is split into at least two portions, each generating a signal. A resulting differential signal produced from the signals generated at each of two detector portions is used to determine whether a defect in the photomask is present, in one embodiment, by generating an image from the resulting signal.

Abstract translation: 提供了用于检测相位缺陷的装置和方法。 本发明通常依赖于当光通过相移掩模（310）中的缺陷以检测这些缺陷时的光的失真。 穿过缺陷的光，例如蚀刻区域中的凸起，将以与通过空气传播的光不同的速度行进。 为了增强从缺陷产生的信号，本发明在几个实施例中通过将光束的焦点设置在待检查的光掩模上方或下方的水平来提供散焦光束（302）。 来自光掩模的光由检测器（314）收集，检测器（314）被分成至少两部分，每个产生一个信号。 在一个实施例中，由在两个检测器部分中的每一个产生的信号产生的所得到的差分信号用于确定光掩模中的缺陷是否通过从所得到的信号产生图像。