Method for determining an imaging function of a mask inspection microscope, and mask inspection microscope
US11243392B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | May 27, 2020 |
| Grant date | Feb 8, 2022 |
| Priority date | — |
| Expiry date | May 27, 2040 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B21/365
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The invention relates to a method for determining an imaging function of a mask inspection microscope, wherein the mask inspection microscope comprises an imaging optical element, a tube, a recording device, an object stage, an illumination unit for measurement with transmitted light and an illumination unit for measurement in reflection, comprising the following method steps: a) measuring the intensities in the pupil plane of the imaging optical element in a reflective measurement, b) measuring the intensities in the pupil plane of the imaging optical element in a transmitted-light measurement, d) Determining the imaging function of the intensities of the imaging optical element, d) determining the imaging function of the intensities of the illumination optical element comprised in the illumination unit for the transmitted-light measurement.Furthermore, the invention relates to a mask inspection microscope for determining the deviation of an actual structure from a desired structure on an object, comprising an imaging optical element, a tube, a recording device, an additional optical module, an illumination unit for measurement with transmitted light, an illumination unit for meas…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.