The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 24, 1986
Filed:
Nov. 21, 1983
Vincent J Coates, Palo Alto, CA (US);
Duane C Holmes, San Jose, CA (US);
Guillermo L Toro-Lira, Mountain View, CA (US);
Nanometrics Incorporated, Sunnyvale, CA (US);
Abstract
In scanning electron microscopes the field established between the focusing lens housing at ground potential and the secondary emission electron detector at a positive potential attracts and carries the secondary electrons to the detector. This field is often displaced from the secondary emission source so that much of the emission is attracted to other areas of the microscope and is lost to the detector. To greatly improve detection efficiency, an electron attracting grid at a potential between that on the detector and the focusing lens housing ground reference potential is interposed between the detector and the specimen and positioned so that the new field established between grid and lens housing dips down toward the specimen surface and thus collects substantially all of the secondary emission electrons which then are attracted to higher potential on the detector.