Indirect determination of a processing parameter

Patent metadata

Field	Value
Publication number	US-10359705-B2
Application number	US-201615764875-A
Country	US
Kind code	B2
Filing date	Sep 21, 2016
Priority date	Oct 12, 2015
Publication date	Jul 23, 2019
Grant date	Jul 23, 2019

Abstract

A method including measuring a value of a directly measureable processing parameter of a patterning process from a portion of a substrate produced by the patterning process; obtaining a relationship between the directly measureable processing parameter and a not directly measureable processing parameter; and determining a value of the not directly measureable processing parameter from the value of the directly measureable processing parameter and the relationship.

First claim

The invention claimed is:

1. A method, comprising:
measuring, by a measurement machine, a value of a directly measureable processing parameter of a patterning process from a portion of a physical substrate physically processed by the patterning process, the directly measureable processing parameter comprising a characteristic of a feature that is part of a device designed to be functional;
obtaining a relationship between the directly measureable processing parameter and a not directly measureable processing parameter; and
determining, by a hardware computer system, a value of the not directly measureable processing parameter from the value of the directly measureable processing parameter and the relationship.

2. The method of claim 1 , wherein the directly measureable processing parameter comprises a critical dimension (CD) of the feature.

3. The method of claim 1 , wherein the feature is a feature in a resist image on the substrate.

4. The method of claim 1 , wherein the not directly measureable processing parameter is a focus at which the portion of the substrate is exposed, or is a dose at which the portion of the substrate is exposed.

5. The method of claim 1 , wherein the relationship is retrieved from a database, established by an experiment or established by simulation.

6. The method of claim 1 , wherein the value of the not directly measureable processing parameter is determined from a median of values of the directly measureable processing parameter.

7. The method of claim 1 , wherein the portion has a higher probability of containing a defect than a threshold, or wherein the portion contains a hot spot.

8. The method of claim 1 , wherein the value of the directly measureable processing parameter is measured from one or more features in the portion.

9. A computer program product comprising a non-transitory computer readable medium having instructions recorded thereon, the instructions configured to cause a computer to at least:
obtain a measured value of a directly measureable processing parameter of a patterning process from a portion of a physical substrate physically processed by the patterning process, the directly measureable processing parameter comprising a characteristic of a feature that is part of a device designed to be functional and the measured value measured by a measurement machine;
obtain a relationship between the directly measureable processing parameter and a not directly measureable processing parameter; and
determine a value of the not directly measureable processing parameter from the value of the directly measureable processing parameter and the relationship.

10. A system comprising:
an inspection apparatus configured to provide a beam on a device pattern on a substrate and to detect radiation redirected by the device pattern; and
the non-transitory computer program product of claim 9 .

11. A method, comprising:
obtaining measured values of a characteristic of a plurality of features or patterns formed on a physical substrate by a lithography process, the measured values obtained using a measurement machine;
obtaining a relationship between the characteristic and a processing parameter of the lithography process;
determining values of the processing parameter for each of the features or patterns based on the values of the characteristic and the relationship;
determining, by a hardware computer system, a statistic characteristic from the values of the processing parameter; and
evaluating the statistic characteristic against a criterion,
where the (i) statistic characteristic, (ii) the result of the evaluation, or (iii) information derived from (i) or (ii), is for control, design, modification or monitoring of a process of manufacturing devices that includes the lithography process or of a physical object or apparatus to be used in process of manufacturing devices.

12. The method of claim 11 , wherein the characteristic relates to geometry of the features or patterns.

13. The method of claim 11 , wherein the characteristic relates locations of the features or patterns relative to the substrate or relative to one another.

14. The method of claim 11 , wherein the processing parameter comprises a dose of the features or patterns or a focus of the features or patterns.

15. The method of claim 11 , wherein the statistic characteristic is a mean, a variance or standard deviation of the values of the processing parameter.

16. The method of claim 11 , further comprising obtaining a further statistic characteristic from values of the processing parameter for features or patterns formed by the same lithography process or a further lithography process.

17. A computer program product comprising a non-transitory computer readable medium having instructions recorded thereon, the instructions when executed by a computer system configured to cause the computer system to at least:
obtain measured values of a characteristic of a plurality of features or patterns formed on a physical substrate by a lithography process, the measured values obtained using a measurement machine;
obtain a relationship between the characteristic and a processing parameter of the lithography process;
determine values of the processing parameter for each of the features or patterns based on the values of the characteristic and the relationship;
determine a statistic characteristic from the values of the processing parameter; and
evaluate the statistic characteristic against a criterion,
where the (i) statistic characteristic, (ii) the result of the evaluation, or (iii) information derived from (i) or (ii), is for control, design, modification or monitoring of a process of manufacturing devices that includes the lithography process or of a physical object or apparatus to be used in process of manufacturing devices.

18. The computer program product of claim 17 , wherein the statistic characteristic is a mean, a variance or standard deviation of the values of the processing parameter.

19. The computer program product of claim 17 , wherein the instructions are further configured to cause the computer system to obtain a further statistic characteristic from values of the processing parameter for features or patterns formed by the same lithography process or a further lithography process.

20. The computer program product of claim 9 , wherein the feature is a feature in a resist image on the substrate.

Assignees

• Asml Netherlands Bv

Inventors

• Wang Te-Sheng

Classifications

• H10P76/2041

  Photolithographic processes · CPC title

• H10P74/203

  Structural properties, e.g. testing or measuring thicknesses, line widths, warpage, bond strengths or physical defects · CPC title

• G03F7/70641

  Focus · CPC title

• G03F7/70558

  Dose control, i.e. achievement of a desired dose · CPC title

• G03F7/70625 Primary

  Dimensions, e.g. line width, critical dimension [CD], profile, sidewall angle or edge roughness · CPC title