Reticle stage based linear dosimeter
US6906781B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Oct 2, 2002 |
| Grant date | Jun 14, 2005 |
| Priority date | — |
| Expiry date | Jun 19, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/70716
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A detector to measure EUV intensity employs a linear array of photodiodes. The detector is particularly suited for photolithography systems that includes: (i) a ringfield camera; (ii) a source of radiation; (iii) a condenser for processing radiation from the source of radiation to produce a ringfield illumination field for illuminating a mask; (iv) a reticle that is positioned at the ringfield camera's object plane and from which a reticle image in the form of an intensity profile is reflected into the entrance pupil of the ringfield camera, wherein the reticle moves in a direction that is transverse to the length of the ringfield illumination field that illuminates the reticle; (v) detector for measuring the entire intensity along the length of the ringfield illumination field that is projected onto the reticle; and (vi) a wafer onto which the reticle imaged is projected from the ringfield camera.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.