Projection exposure tool for microlithography and method for microlithographic imaging

Patent metadata

Field	Value
Publication number	US-9442393-B2
Application number	US-201414524486-A
Country	US
Kind code	B2
Filing date	Oct 27, 2014
Priority date	Sep 28, 2010
Publication date	Sep 13, 2016
Grant date	Sep 13, 2016

Abstract

A projection exposure tool for microlithography for imaging mask structures of an image-providing substrate onto a substrate to be structured includes a measuring apparatus configured to determine a relative position of measurement structures disposed on a surface of one of the substrates in relation to one another in at least one lateral direction with respect to the substrate surface and to thereby simultaneously measure a number of measurement structures disposed laterally offset in relation to one another.

First claim

What is claimed is:

1. A tool, comprising:
a measuring apparatus configured to determine a relative position of measurement structures relative to each other in a lateral direction,
wherein:
the tool is a microlithography projection exposure tool configured to image mask structures of a first substrate onto a second substrate which is different from the first substrate;
the measurement structures are disposed on a surface of the first substrate, or the measurement structures are disposed on a surface of the second substrate; and
the measuring apparatus is configured so that, during use of the measuring apparatus, the measuring apparatus determines, via simultaneous interferometric measurement, relative lateral positions of at least three measurement structures which are laterally offset relative to each other.

2. The tool of claim 1 , wherein the measuring apparatus is configured to simultaneously measure the lateral relative position of measurement structures distributed over the whole substrate surface comprising the measurement structures.

3. The tool of claim 1 , wherein the measuring structures are on the surface of the second substrate.

4. The tool of claim 1 , wherein the measuring apparatus comprises at least two reflective elements configured to reflect back onto the measurement structures measuring light divided into two measuring beams by diffraction on the measurement structures.

5. The tool of claim 1 , wherein the measuring apparatus comprises a beam splitter for splitting measuring light into two measuring beams with different propagation directions before striking the substrate to be measured.

6. The tool of claim 5 , wherein the beam splitter comprises a diffraction grating.

7. The tool of claim 5 , wherein the measuring apparatus is configured to irradiate the measuring light at an angle to the substrate surface to be measured onto the beam splitter.

8. The tool of claim 5 , wherein the measuring apparatus is configured to superimpose coherently images of the measurement structures generated via the two measuring beams.

9. The tool of claim 1 , wherein the measuring apparatus is configured to determine distortion over the substrate surface from the lateral position measurements, and the projection exposure tool further comprises an exposure control device which is configured to adapt a local imaging scale dynamically to the distortion when exposing the substrate.

10. The tool of claim 1 , wherein the measuring apparatus is configured to take topography measurements at a number of points of the substrate surface simultaneously.

11. The tool of claim 1 , wherein the measuring apparatus is configured to take the lateral position measurements with measuring light of a first wavelength, and the topography measurements with measuring light of a second wavelength.

12. The tool of claim 11 , wherein the measuring apparatus comprises a diffraction grating configured to split the measuring light of the first wavelength into two measuring beams, and the diffraction grating being configured so that at least 90% of the measuring light of the second wavelength passes through the diffraction grating without being diffracted.

13. The tool of claim 12 , wherein the diffraction grating is tilted relative to the propagation direction of the measuring light of the second wavelength.

14. The tool of claim 1 , wherein the measuring apparatus is configured to take the measurement of the whole substrate surface in less than 10 seconds.

15. The tool of claim 1 , wherein the measuring structures are on the surface of the second substrate, and the measuring apparatus comprises a beam splitter for splitting measuring light into two measuring beams with different propagation directions before striking the substrate to be measured.

16. The tool of claim 1 , wherein the measuring structures are on the surface of the second substrate, the measuring apparatus comprises a diffraction grating configured to split the measuring light of the first wavelength into two measuring beams, and the diffraction grating being configured so that at least 90% of the measuring light of the second wavelength passes through the diffraction grating without being diffracted.

17. A method, comprising:
using interferometric measurement to simultaneously determine relative lateral positions of at least three measurement structures with respect to a substrate on which the at least three measurement structures are laterally offset relative to each other, the substrate being a first substrate or a second substrate; and
using a microlithography projection exposure tool to image mask structures on the first substrate onto the second substrate while simultaneously locally varying an imaging parameter based on the lateral position measurements.

18. The method of claim 17 , comprising locally varying an imaging scale while exposing the substrate.

19. The method of claim 17 , wherein the measurement structures disposed on the substrate comprise diffraction gratings of different periodicities.

20. The method of claim 17 , wherein the measurement marks are on the second substrate, and an entirety of the measurement structures forms a web structure with a plurality of web meshes which surround structurable product areas with a single exposure of the first substrate.

Assignees

• Zeiss Carl Smt Gmbh

Inventors

• Hetzler Jochen
• Goehnermeier Aksel

Classifications

• G03F7/70733

  Handling masks and workpieces, e.g. exchange of workpiece or mask, transport of workpiece or mask · CPC title

• G01B2290/65

  Spatial scanning object beam · CPC title

• G03F9/7049

  Technique, e.g. interferometric · CPC title

• G03F9/7003 Primary

  Alignment type or strategy, e.g. leveling, global alignment · CPC title

• G01B9/02015

  characterised by the beam path configuration · CPC title