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:
May. 12, 2015
Filed:
Nov. 14, 2011
Jan Andries Meijer, Rotterdam, NL;
Jan Andries Meijer, Rotterdam, NL;
Mapper Lithography IP B.V., Delft, NL;
Abstract
The invention relates to a method for determining a distance between charged particle beamlets in a multi-beamlet exposure apparatus. The apparatus is provided with a sensor comprising a converter element for converting charged particle energy into light and a light sensitive detector provided with a two-dimensional pattern of beamlet blocking and non-blocking regions. The method comprises scanning a first beamlet over the pattern, receiving light generated by the converter element, and converting the received light into a first signal. Then the two-dimensional pattern and the first beamlet are moved relatively with respect to each other over a predetermined distance. Subsequently, the method comprises scanning a second beamlet over the pattern, receiving light generated by the converter element, and converting the received light into a second signal. Finally, the distance between the first beamlet and second beamlet is determined based on the first signal, the second signal and the predetermined distance.