Patent · US Active

Method for detecting an object structure and apparatus for carrying out the method

US11892769B2 · kind B2 · utility

1Cited by

3References

23Claims

0Family size

Assignee

Carl Zeiss SMT GmbH · DE

Inventors

Beat Marco Mout · Aalen, DE
Dirk Seidel · Jena, DE
Christoph Husemann · Jena, DE
Ulrich Matejka · Jena, DE

Key dates

Filing date	Sep 11, 2020
Grant date	Feb 6, 2024
Priority date	—
Expiry date	Sep 23, 2042

Classification

Technology area (CPC G)Physics
CPC primaryG01B2210/56
WIPO fieldOptics
WIPO sectorInstruments

Abstract

When detecting an object structure, at least one portion of the object is initially illuminated with illumination light of an at least partly coherent light source from at least one preferred illumination direction. At least one diffraction image of the illuminated portion is recorded by spatially resolved detection of the diffraction intensity of the illumination light, diffracted by the illuminated portion, in a detection plane. At least one portion of the object structure is reconstructed from the at least one recorded diffraction image using an iterative method. Here, the iteration diffraction image of a raw object structure is calculated starting from an iteration start value and said raw object structure is compared to the recorded diffraction image in each iteration step. The iteration start value is taken by starting from a raw object structure of the object structure to be detected, which is obtained by an iteration start value ascertainment method that is independent of the remaining detection method. This yields a method in which a detection of an object structure is designed to be insensitive at a given accuracy.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.