Process window identifier

Patent metadata

Field	Value
Publication number	US-9842186-B2
Application number	US-201514861847-A
Country	US
Kind code	B2
Filing date	Sep 22, 2015
Priority date	Sep 22, 2014
Publication date	Dec 12, 2017
Grant date	Dec 12, 2017

Abstract

Disclosed herein is a computer-implemented method for determining an overlapping process window (OPW) of an area of interest on a portion of a design layout for a device manufacturing process for imaging the portion onto a substrate, the method comprising: obtaining a plurality of features in the area of interest; obtaining a plurality of values of one or more processing parameters of the device manufacturing process; determining existence of defects, probability of the existence of defects, or both in imaging the plurality of features by the device manufacturing process under each of the plurality of values; and determining the OPW of the area of interest from the existence of defects, the probability of the existence of defects, or both.

First claim

The invention claimed is:

1. A method of determining an overlapping process window (OPW) of an area of interest on a portion of a design layout for a device manufacturing process for imaging the portion onto a substrate, the method comprising:
obtaining a plurality of features in the area of interest;
obtaining a plurality of values of one or more processing parameters of the device manufacturing process;
determining, by a computer system, an existence of a defect, a probability of the existence of a defect, or both, in imaging each of the plurality of features by the device manufacturing process under each of the plurality of values;
determining, by the computer system, the OPW of the area of interest including the plurality of features from the existence of a defect, the probability of the existence of a defect, or both; and
producing electronic data using the OPW to configure an aspect of the device manufacturing process.

2. The method of claim 1 , wherein the plurality of features is selected based on data representing the design layout.

3. The method of claim 1 , wherein the existence of a defect, the probability of the existence of a defect, or both, are determined from one or more characteristics of individual process windows (IPWs) of the plurality of features without actually determining the entire IPWs.

4. The method of claim 3 , further comprising compiling the one or more characteristics into a map.

5. The method of claim 1 , wherein the existence of a defect, the probability of the existence of a defect, or both, is determined from individual process windows (IPWs) of the plurality of features.

6. The method of claim 1 , wherein the existence of a defect, the probability of the existence of a defect, or both, is determined using an empirical rule.

7. The method of claim 6 , wherein the empirical rule is a classifier or a database.

8. The method of claim 7 , wherein the classifier takes the plurality of values and one or more characteristics of the plurality of features as input and outputs the existence of a defect, the probability of the existence of a defect, or both.

9. The method of claim 8 , wherein the classifier is selected from a group consisting of: logistic regression and multinomial logit, probit regression, the perceptron algorithm, support vector machine, import vector machine, and linear discriminant analysis.

10. The method of claim 1 , wherein the existence of a defect, the probability of the existence of a defect, or both, is determined using a computational model that calculates or simulates a portion or a characteristic of images of the plurality of features, and determines the existence of a defect, the probability of the existence of a defect, or both, from the portion or the characteristic.

11. The method of claim 1 , wherein the existence of a defect, the probability of the existence of a defect, or both, is determined using experimental data obtained from a substrate inspection tool.

12. The method of claim 1 , wherein the defect is selected from a group consisting of necking, line pull back, line thinning, critical dimension error, overlapping, resist top loss, resist undercut, and bridging.

13. The method of claim 1 , wherein one or more of the one or more processing parameters are selected from a group consisting of: focus, dose, a characteristic of an illumination source, a characteristic of projection optics, a characteristic of a resist, data obtained from metrology, data from an operator of a processing apparatus used in the device manufacturing process, a characteristic of development of the resist, a characteristic of post-exposure baking of the resist, and a characteristic of etching.

14. The method of claim 1 , further comprising determining individual process windows (IPWs) of the plurality of features.

15. The method of claim 14 , wherein determination of the OPW comprises overlapping the IPWs.

16. The method of claim 1 , further comprising selecting a point in the OPW and conducting the device manufacturing process under values of the processing parameters represented by this point.

17. The method of claim 16 , wherein the point is farthest from any boundary of the OPW.

18. The method of claim 1 , wherein the plurality of features comprise a processing window limiting pattern (PWLP).

19. The method of claim 1 , wherein the device manufacturing process involves using a lithography apparatus.

20. The method of claim 1 , wherein the area of interest comprises a processing window limiting pattern (PWLP).

21. The method of claim 1 , wherein the area of interest comprises two or more disconnected portions of the design layout.

22. The method of claim 1 , further comprising determining a global process window of the portion of the design layout from the OPW.

23. The method of claim 1 , wherein at least one of the plurality of values is outside an individual process window (IPW) of at least one of the plurality of features.

24. The method of claim 1 , wherein the plurality of values comprise a plurality of sets of values of a plurality of the processing parameters.

25. A non-transitory computer program product comprising a computer readable medium having instructions recorded thereon, the instructions when executed configured to cause a computer system to:
obtain a plurality of features in an area of interest on a portion of a design layout for a device manufacturing process for imaging the portion onto a substrate;
obtain a plurality of values of one or more processing parameters of the device manufacturing process;
determine an existence of a defect, a probability of the existence of a defect, or both, in imaging each of the plurality of features by the device manufacturing process under each of the plurality of values;
determine overlapping process window (OPW) data of the area of interest including the plurality of features from the existence of a defect, the probability of the existence of a defect, or both; and
produce electronic data using the OPW data to configure an aspect of the device manufacturing process.

26. The non-transitory computer program product of claim 25 , wherein the instructions are configured to cause the computer system to determine the existence of a defect, the probability of the existence of a defect, or both, from one or more characteristics of individual process windows (IPWs) of the plurality of features without actually determining the entire IPWs.

Assignees

• Asml Netherlands Bv

Inventors

• Chen Frank Gang
• De Vocht Joseph Werner
• Du Yuelin
• Li Wanyu
• Lu Yen-Wen

Classifications

• G06F30/398 Primary

  Design verification or optimisation, e.g. using design rule check [DRC], layout versus schematics [LVS] or finite element methods [FEM] (optical proximity correction [OPC] design processes G03F1/36) · CPC title

• G03F7/70508

  Data handling in all parts of the microlithographic apparatus, e.g. handling pattern data for addressable masks or data transfer to or from different components within the exposure apparatus · CPC title

• G03F7/70641

  Focus · CPC title

• G03F7/70666

  Aerial image, i.e. measuring the image of the patterned exposure light at the image plane of the projection system · CPC title

• G03F7/70625

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