Real time telecentricity measurement
US7999939B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 17, 2007 |
| Grant date | Aug 16, 2011 |
| Priority date | — |
| Expiry date | Jul 5, 2029 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/70191
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Systems and methods are provides for measuring and correcting for a given telecentricity in a lithographic apparatus. A radiation beam is partitioned into a plurality of beams, each of which is modulated using an array of individually controllable elements and projected onto a portion of a substrate through a projection system. A set of alignment beams is transmitted simultaneously on paths similar to those traversed by the plurality of radiation beams, and a corresponding set of sensors respectively measures an angle and a position of the set of alignment beams proximate to an entrance of the projection system. An assembly of telecentricity control mirrors (TCM) adjusts appropriate ones of the plurality of radiation beams in response to the measurement to correct for any detected telecentricity errors.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.