Method of controlling a lithographic apparatus, device manufacturing method, lithographic apparatus, computer program product and method of improving a mathematical model of a lithographic process

Patent metadata

Field	Value
Publication number	US-9696635-B2
Application number	US-201213416387-A
Country	US
Kind code	B2
Filing date	Mar 9, 2012
Priority date	Mar 11, 2011
Publication date	Jul 4, 2017
Grant date	Jul 4, 2017

Abstract

A method of controlling a lithographic apparatus, the method including setting an illumination system of the lithographic apparatus to effect a selected illumination mode, measuring a value of a first parameter of the lithographic apparatus, calculating a value of a second parameter of a projected image of a feature of a test pattern having a plurality of features using a model of the lithographic apparatus and the measured value of the first parameter, and controlling the lithographic apparatus with reference to the calculated value of the second parameter.

First claim

The invention claimed is:

1. A method of controlling a lithographic projection apparatus, the method comprising:
measuring a value of a first parameter of the lithographic projection apparatus when set to effect a selected illumination mode;
calculating a value of a second parameter of a projected image of a feature of a pattern using a model of the lithographic projection apparatus and the measured value of the first parameter, wherein the model comprises a simulation model of illumination of a patterning device, patterning of the illumination by the patterning device and projecting of the patterned illumination;
controlling the lithographic projection apparatus based on the measured first parameter by changing a control setting of the lithographic apparatus; and
further controlling the lithographic projection apparatus with reference to the calculated value of the second parameter by further changing the control setting or changing another control setting, of the lithographic projection apparatus.

2. The method according to claim 1 , wherein the second parameter is one or more selected from the group consisting of: critical dimension; critical dimension uniformity; and critical dimension through pitch.

3. The method according to claim 1 , wherein the first parameter is one or more selected from the group consisting of: intensity at one or more positions in a pupil plane of an illumination system of the lithographic projection apparatus; bandwidth of radiation of the illumination mode; apodization of a projection system of the lithographic projection apparatus; and polarization of radiation of the illumination mode.

4. The method according to claim 1 , wherein calculating a value of the second parameter comprises calculating values of the second parameter for respective ones of a plurality of features of the pattern, the plurality of features including features that are different in pitch, or orientation, or both pitch and orientation.

5. The method according to claim 1 , wherein changing the control setting affects the first parameter.

6. The method according to claim 1 , wherein the model is one or more selected from the group consisting of: an aerial image model and a resist model.

7. The method according to claim 1 , further comprising:
performing an exposure of the pattern onto a substrate;
measuring a value of the second parameter in a pattern formed on the substrate; and
comparing the calculated value of the second parameter and the measured value of the second parameter.

8. The method according to claim 7 , further comprising adjusting the model of the lithographic apparatus with reference to the comparison between the calculated value of the second parameter and the measured value of the second parameter.

9. The method according to claim 7 , wherein measuring the value of the second parameter is performed using a scatterometer.

10. The method according to claim 1 , wherein the illumination mode defines an intensity distribution across directions of illumination of the patterning device.

11. The method according to claim 10 , wherein the lithographic projection apparatus comprises a programmable device arranged to direct radiation into a plurality of directions of illumination of the patterning device.

12. The method according to claim 11 , wherein the programmable device comprises an array of individually controllable mirrors.

13. The method according to claim 12 , further comprising adjusting an offset value applied to at least one of the individually controllable mirrors with reference to the calculated value of the second parameter.

14. The method according to claim 1 , wherein controlling the lithographic projection apparatus with reference to the calculated value of the second parameter comprises using the calculated value to determine a setting of one or more selected from the following:
a position of a mirror in a programmable mirror array used to define the illumination mode;
a setting of a zoom-axicon device;
a setting of a dose control device;
a setting of a radiation source;
a setting of a projection system; and
a setting of a support of the patterning device or of a radiation-sensitive substrate.

15. The method according to claim 1 , wherein the method is performed prior to use of the lithographic projection apparatus for production of devices.

16. The method according to claim 1 , wherein the method is performed periodically.

17. A device manufacturing method using a lithographic projection apparatus, the method comprising:
measuring a value of a first parameter of the lithographic projection apparatus when set to effect a selected illumination mode;
calculating a value of a second parameter of a projected image of a feature of a test pattern, separate from a product pattern, using a model of the lithographic projection apparatus and the measured value of the first parameter, wherein the model comprises a simulation model of illumination of a patterning device, patterning of the illumination by the patterning device and projecting of the patterned illumination;
changing a control setting of the lithographic apparatus with reference to the calculated value of the second parameter; and
imaging the product pattern onto the substrate using the illumination mode and the changed control setting.

18. A lithographic apparatus arranged to image a pattern comprising a plurality of features onto a substrate, the lithographic apparatus comprising:
a support for a patterning device;
a controllable illumination system arranged to illuminate the patterning device;
a projection system arranged to project an image of the patterning device onto the substrate; and
a control system arranged to:
measure a value of a first parameter of the lithographic projection apparatus when set to effect a selected illumination mode;
calculate a value of a second parameter of a projected image of a feature of a pattern using a model of the lithographic apparatus and the measured value of the first parameter, wherein the model comprises a simulation model of the illumination of the patterning device, the patterning of the illumination by the patterning device and the projecting of the image of the patterning device;
control the lithographic projection apparatus based on the measured first parameter by changing a control setting of the lithographic apparatus; and
further control the lithographic projection apparatus with reference to the calculated value of the second parameter by further changing the control setting or changing another control setting, of the lithographic projection apparatus.

19. A computer program product comprising a non-transitory computer-readable storage medium having stored thereon instructions for performing a method of controlling a lithographic projection apparatus, the method comprising:
measuring a value of a first parameter of the lithographic projection apparatus when set to effect a selected illumination mode;
calculating a value of a second parameter of a projected image of a feature of a pattern using a model of the lithographic projection apparatus and the measured value of the first parameter, wherein the model comprises a simulation model of illumination of a patterning device, patterning of the illumination by the patterning device and projecting of the patterned illumination;
controlling the lithographic projection apparatus based on the measured first parameter by changing a control setting of the lithographic apparatus; and
further controlling the lithographic projection appara

Assignees

• Engelen Adrianus Fransiscus Petrus
• Megens Henricus Johannes Lambertus
• Mulkens Johannes Catharinus Hubertus
• Kazinczi Robert
• Wang Jen-Shiang
• Asml Netherlands Bv

Inventors

• Engelen Adrianus Fransiscus Petrus
• Megens Henricus Johannes Lambertus
• Mulkens Johannes Catharinus Hubertus
• Kazinczi Robert
• Wang Jen-Shiang

Classifications

• G03F7/70616

  Monitoring the printed patterns · CPC title

• G03F7/705 Primary

  Modelling or simulating from physical phenomena up to complete wafer processes or whole workflow in wafer productions · CPC title

• G03F7/70091

  Illumination settings, i.e. intensity distribution in the pupil plane or angular distribution in the field plane; On-axis or off-axis settings, e.g. annular, dipole or quadrupole settings; Partial coherence control, i.e. sigma or numerical aperture [NA] · CPC title

• G03F7/706837

  Data analysis, e.g. filtering, weighting, flyer removal, fingerprints or root cause analysis · CPC title

• G03F7/706849

  Irradiation branch, e.g. optical system details, illumination mode or polarisation control · CPC title