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:
Jul. 05, 1983
Filed:
Aug. 03, 1981
Kenneth C Smith, Cambridge, GB;
National Research Development Corporation, London, GB;
Abstract
In electron beam lithography apparatus a substrate, on which an exposure pattern is to be produced, is exposed to a plurality of electron beams. In a double beam arrangement one beam is capable of the highest resolution required and has a necessarily low writing speed. The other beam is relatively coarse in beam width but carries a higher current and has a much higher writing speed. Single-pole magnetic lens focusing is used with close angular spacing between the beams. Scanning of the pattern is programmed for economy of time so that the beams produce complementary portions of the pattern, the fine beam defining for example the edges of a structure while the coarse beam scans the area bounded by the edges. Scanning may be simultaneous or sequential. Selection of the relative values of beam potential and the use of energy selective detectors enable the two scanned regions to be imaged.