06852973 is referenced by 21 patents and cites 7 patents.

The present invention sets out to provide a scanning charged particle microscope equipped with a rapid control function capable of extrapolating an in-focus point from image information for a single frame and an automatic focusing system capable of reliably and precisely carrying out a focusing operation for a horizontal pattern image. The automatic focusing system provided in the scanning charged particle microscope of the present invention is provided with means for changing a focal point each raster scan line, and control means for comparing image information each scanning line and extrapolating focusing positions. The scanning line can then be made to be an inclined scanning line that is a combination of a horizontal component and a vertical component with respect to a chip array on a semiconductor wafer. Further, a method is adopted comprising a first step of reliably taking in a coarse in-focus point and a second step of detecting the in-focus point with a high degree of precision.

Title
Scanning charged particle microscope
Application Number
10/410224
Publication Number
6852973 (B2)
Application Date
April 9, 2003
Publication Date
February 8, 2005
Inventor
Atsushi Uemoto
Chiba
JP
Hidekazu Suzuki
Chiba
JP
Agent
Adams & Wilks
Assignee
SII NanoTechnology
JP
IPC
G01N 013/16
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