Selection of measurement locations for patterning processes

1. A method comprising:

obtaining pattern data describing a pattern to be applied to substrates in a patterning process;

obtaining a process characteristic measured during, or following, processing of a substrate of the substrates, the process characteristic characterizing the processing of the substrate;

determining, by a hardware computer, a simulated result of the patterning process based on the pattern data and the process characteristic; and

selecting, based on the simulated result, a location for at least one substrate of the substrates where at least a feature of the pattern is, or expected to be, out of tolerance.

2. The method of claim 1 , wherein obtaining pattern data comprises obtaining a reticle model or design layout.

3. The method of claim 1 , wherein obtaining a process characteristic comprises obtaining a process characteristic measured during patterning of the substrate, the process characteristic comprising a process parameter set point or an observed characteristic of the patterning.

4. The method of claim 3 , wherein obtaining a process characteristic measured during patterning of the substrate comprises:

obtaining a leveling measurement indicative of an orientation of at least part of a surface of the substrate relative to a lithography apparatus performing the patterning process, and/or

obtaining an intensity of radiation used in the patterning process, and/or

obtaining a stage performance parameter of a stage holding the substrate during at least part of the patterning process, and/or

obtaining a value indicative of thermal distortion of an optical element used in the patterning process, and/or

obtaining a value indicative of pre or post exposure processing of resist during the patterning process.

5. The method of claim 1 , wherein obtaining a process characteristic comprises obtaining a process characteristic measured before at least one process of patterning the substrate.

6. The method of claim 5 , wherein obtaining a process characteristic measured before at least one process of patterning the substrate comprises:

obtaining a film thickness of a layer of the substrate, and/or

obtaining a value indicative of an amount of misalignment between patterns in two layers of the substrate.

7. The method of claim 1 , wherein determining a simulated result of the patterning process comprises:

simulating the patterning process with means for modeling the patterning process, and/or

predicting a dimension of the pattern applied to a substrate based on a computational lithographic simulation comprising:

a projection optics model; and

a resist model.

8. The method of claim 1 , further comprising:

obtaining additional values of the process characteristic, the additional values being measured during or following the processing of a plurality of substrates including the substrate;

simulating the patterning process for each of the plurality of substrates based on the pattern data and corresponding instances of the process characteristic, to produce a plurality of simulation results; and

selecting, based on the plurality of simulation results, a substrate from among the plurality of substrates, the substrate being selected to undergo a measurement.

9. The method of claim 1 , further comprising:

scoring a plurality of candidate locations based on differences between the simulated result and one or more tolerances of the pattern; and

selecting, based on relative values of the scores, the locations from among the candidate locations.

10. The method of claim 1 , further comprising:

measuring a substrate at the location; and

adjusting the patterning process based on a measured value from the measurement location.

11. A tangible, non-transitory, machine readable media storing instructions, the instructions, when executed by a data processing apparatus, are configured to cause the data processing apparatus to at least:

obtain pattern data describing a pattern to be applied to substrates in a patterning process;

obtain a process characteristic measured during, or following, processing of a substrate of the substrates, the process characteristic characterizing the processing of the substrate;

determine a simulated result of the patterning process based on the pattern data and the process characteristic; and

select, based on the simulated result, a location for at least one substrate of the substrates where at least a feature of the pattern is, or expected to be, a failure or out of tolerance.

12. The machine-readable medium of claim 11 , wherein the determination of a simulated result of the patterning process comprises:

simulation of the patterning process with means for modeling the patterning process, and/or

prediction of a dimension of the pattern applied to a substrate based on a computational lithographic simulation comprising:

a projection optics model; and

a resist model.

13. The machine-readable medium of claim 11 , wherein the instructions are further configured to cause the data processing apparatus to:

obtain additional values of the process characteristic, the additional values being measured during, or following, the processing of a plurality of substrates including the substrate;

simulate the patterning process for each of the plurality of substrates based on the pattern data and corresponding instances of the process characteristic, to produce a plurality of simulation results; and

select, based on the plurality of simulation results, a substrate from among the plurality of substrates, the substrate being selected to undergo a measurement.

14. The machine-readable medium of claim 11 , wherein the instructions are further configured to cause the data processing apparatus to:

score a plurality of candidate locations based on differences between the simulated result and one or more tolerances of the pattern; and

select, based on relative values of the scores, the location from among the candidate locations.

15. A method comprising:

obtaining pattern data describing a pattern to be applied to substrates in a patterning process;

obtaining a process characteristic measured during, or following, processing of a substrate of the substrates, the process characteristic characterizing the processing of the substrate;

determining, by a hardware computer, a computed or modeled result of the patterning process using the pattern data and the process characteristic as inputs into the computation or modeling; and

selecting, based on the computed or modelled result, a location for at least one substrate of the substrates where at least a feature of the pattern is, or expected to be, out of tolerance.

16. The method of claim 15 , further comprising:

scoring a plurality of candidate locations based on differences between the simulated result and one or more tolerances of the pattern; and

selecting, based on relative values of the scores, the locations from among the candidate locations.

17. The method of claim 15 , wherein obtaining a process characteristic comprises obtaining a process characteristic measured during patterning of the substrate, the process characteristic comprising a process parameter set point or an observed characteristic of the patterning.

18. The method of claim 17 , wherein obtaining a process characteristic measured during patterning of the substrate comprises:

obtaining a leveling measurement indicative of an orientation of at least part of a surface of the substrate relative to a lithography apparatus performing the patterning process, and/or

obtaining an intensity of radiation used in the patterning process, and/or

obtaining a stage performance parameter of a stage holding the substrate during at least part of the patterning process, and/or

obtaining a value indicative of thermal distortion of an optical element used in the patterning process, and/or

obtaining a value indicative of pre or post exposure processing of resist during the patterning process.

19. The method of claim 15 , further comprising:

measuring a substrate at the location; and

adjusting the patterning process based on a measured value from the measurement location.

20. A tangible, non-transitory, machine readable media storing instructions, the instructions, when executed by a data processing apparatus, are configured to cause the data processing apparatus to at least perform the method of claim 15 .