Method and apparatus to determine a patterning process parameter

Patent metadata

Field	Value
Publication number	US-11710668-B2
Application number	US-202017072391-A
Country	US
Kind code	B2
Filing date	Oct 16, 2020
Priority date	Mar 1, 2016
Publication date	Jul 25, 2023
Grant date	Jul 25, 2023

Abstract

A metrology target includes: a first structure arranged to be created by a first patterning process; and a second structure arranged to be created by a second patterning process, wherein the first structure and/or second structure is not used to create a functional aspect of a device pattern, and wherein the first and second structures together form one or more instances of a unit cell, the unit cell having geometric symmetry at a nominal physical configuration and wherein the unit cell has a feature that causes, at a different physical configuration than the nominal physical configuration due to a relative shift in pattern placement in the first patterning process, the second patterning process and/or another patterning process, an asymmetry in the unit cell.

First claim

The invention claimed is:

1. A metrology target comprising:
a first structure arranged to be created by a first patterning process; and
a second structure arranged to be created by a second patterning process, wherein the first structure and/or second structure is not used to create a functional aspect of a device pattern,
wherein the first and second structures together form one or more instances of a unit cell, the unit cell having geometric symmetry at a nominal physical configuration and wherein the unit cell has a feature that causes, at a different physical configuration than the nominal physical configuration due to a relative shift in pattern placement in the first patterning process, the second patterning process and/or another patterning process, an asymmetry in the unit cell, and
wherein the first structure comprises a structure being essentially elongate in a first direction with a first dimension in a second direction substantially perpendicular to the first direction and/or a first type of material and the second structure comprises a structure being essentially elongate in the first direction with a second dimension in the second direction or a second type of material, wherein the feature comprises the first dimension and/or the first type of material being different than the second dimension and/or the second type of material.

2. The target of claim 1 , wherein the first structure comprises closed curve structures and the second structure comprises closed curve structures.

3. The target of claim 1 , wherein structures of the first structure are arranged in a first array in a direction substantially perpendicular to a direction in which structures are arranged in a third array of structures.

4. A computer program product comprising a computer non-transitory readable medium having a data structure therein, the data structure corresponding to the metrology target of claim 1 .

5. One or more reticles comprising one or more patterns configured to facilitate production of the first and second structures of the metrology target of claim 1 .

6. The target of claim 1 , wherein the first structure comprises structures arranged in an array in the second direction and at least one such structure comprises a plurality of sub-structures separated by one or more voids or one or more cuts arranged along the first direction and/or the second structure comprises structures arranged in an array in the second direction and at least one such structure comprises a plurality of sub-structures separated by one or more voids or one or more cuts arranged along the first direction,
wherein the feature comprises the one or more voids or one or more cuts of the first structure and/or the second structure.

7. The target of claim 6 , wherein the voids or cuts of the first structure and/or the second structure are produced using a different patterning process than the first and second patterning processes.

8. The target of claim 6 , wherein the first structure comprises the voids or cuts and the second structure comprises the voids.

9. The target of claim 8 , wherein the voids or cuts of the first structure have a different pitch than the voids or cuts of the second structure.

10. The target of claim 8 , wherein at least one void or cut of the first structure lines up with at least one void or cut of the second structure at the nominal physical configuration.

11. A method comprising:
creating a first structure for a metrology target, the first structure to be created by a first patterning process that creates a corresponding device feature of a device;
creating a second structure for the metrology target, the second structure to be created by a second patterning process that creates a further corresponding device feature of device, wherein the first and second structures together form one or more instances of a unit cell, the unit cell having geometric symmetry at a nominal physical configuration; and
introducing a feature within the first structure and/or within the second structure that causes, at a different physical configuration than the nominal physical configuration due to a relative shift in location of device features in the device from an expected location of the device features in the device, an asymmetry in the unit cell.

12. The method of claim 11 , wherein a feature of the first structure has a substantially same dimension and/or pitch as the corresponding feature of the device and/or a feature of the second structure has a substantially same dimension and/or pitch as the corresponding feature of the device.

13. The method of claim 11 , wherein the feature in the metrology target causes a first type of asymmetry in the unit cell for a relative shift in a first direction and causes a second different type of asymmetry in the unit cell for a relative shift in a second different direction.

14. A computer program product comprising a computer non-transitory readable medium having instructions therein, the instructions, when executed by a computer system, configured to cause the computer system to cause the method of claim 11 .

15. The method of claim 11 , further comprising evaluating one or more selected from: printability of the metrology target, detectability of the metrology target, robustness of the metrology target to process variations, and/or matching of the metrology target to a device pattern.

16. The method of claim 15 , comprising iteratively evaluating matching of the metrology target to a device pattern and detectability of the metrology target.

17. A metrology target comprising:
a first structure arranged to be created by a first patterning process; and
a second structure arranged to be created by a second patterning process, wherein the first structure and/or second structure is not used to create a functional aspect of a device pattern,
wherein the first and second structures together form one or more instances of a unit cell, the unit cell having geometric symmetry at a nominal physical configuration and wherein the unit cell has a feature that causes, at a different physical configuration than the nominal physical configuration due to a relative shift in pattern placement in the first patterning process, the second patterning process and/or another patterning process, an asymmetry in the unit cell, and
wherein the first and/or second structure comprises a plurality of structures having one or more voids or cuts therein, and
wherein the structures of the first and/or second structure are configured for determination of a parameter associated with the first and second patterning processes in a first direction and the one or more voids or cuts are configured for determination of a parameter associated with the first and second patterning processes in a second direction different from the first direction.

18. The target of claim 17 , wherein the one or more voids or cuts are produced using a different patterning process than the first and second patterning processes.

19. The target of claim 17 , wherein the first structure comprises the one or more voids and/or cuts and the second structure comprises the one or more voids and/or cuts.

20. The target of claim 17 , wherein structures of the first structure are arranged in a first array in a direction substantially perpendicular to a direction in which structures of the second structure are arranged in a second array or in which structures are arranged in a third array of structures.

Assignees

• Asml Netherlands Bv

Inventors

• Van Leest Adriaan Johan
• Tsiatmas Anagnostis
• Hinnen Paul Christiaan
• Mcnamara Elliott Gerard
• Verma Alok
• Theeuwes Thomas
• Cramer Hugo Augustinus Joseph
• De La Fuente Valentin Maria Isabel
• Van Witteveen Koen
• Zaal Martijn Maria
• Wang shu-jin

Classifications

• H10P74/203 Primary

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

• H10P50/691

  for Group V materials or Group III-V materials · CPC title

• G03F7/706851

  Detection branch, e.g. detector arrangements, polarisation control, wavelength control or dark/bright field detection · CPC title

• G03F7/706847

  Production of measurement radiation, e.g. synchrotron, free-electron laser, plasma source or higher harmonic generation [HHG] · CPC title

• G06F2119/18

  Manufacturability analysis or optimisation for manufacturability · CPC title