公开(公告)号：US20170084424A1

公开(公告)日：2017-03-23

申请号：US15272194

申请日：2016-09-21

Applicant: KLA-Tencor Corporation

Inventor： Doug K. Masnaghetti ,  Richard R. Simmons ,  Scott A. Young ,  Mark A. McCord ,  Rainer Knippelmeyer

IPC: H01J37/22 ,  H01J37/20 ,  H01J37/06 ,  H01J37/153 ,  H01J37/10 ,  H01J37/28 ,  H01J37/244

CPC classification number: H01J37/153 ,  H01J37/21 ,  H01J37/28 ,  H01J2237/12 ,  H01J2237/1532 ,  H01J2237/216 ,  H01J2237/221

Abstract: A scanning electron microscopy system is disclosed. The system includes a multi-beam scanning electron microscopy (SEM) sub-system. The SEM sub-system includes a multi-beam electron source configured to form a plurality of electron beams, a sample stage configured to secure a sample, an electron-optical assembly to direct the electron beams onto a portion of the sample, and a detector assembly configured to simultaneously acquire multiple images of the surface of the sample. The system includes a controller configured to receive the images from the detector assembly, identify a best focus image of images by analyzing one or more image quality parameters of the images, and direct the multi-lens array to adjust a focus of one or more electron beams based on a focus of an electron beam corresponding with the identified best focus image.