Mask-Patterns Including Intentional Breaks

• US 20070196742A1
• Filed: 10/04/2006
• Published: 08/23/2007
• Est. Priority Date: 10/04/2005
• Status: Active Grant

• Current Assignee: Synopsys Incorporated
• Original Assignee: Luminescent Technologies, Inc. (KLA Corporation)
• Inventors: Liu, Yong, Abrams, Daniel, Peng, Danping, Rissman, Paul
• Granted Patent: US 7,793,253 B2
• Time in Patent Office: Days
• US Class Current: 430/5
• CPC Class Codes: G03F 1/36 Masks having proximity correction features; Preparation thereof, e.g. optical proximity correction [OPC] design processes

Abstract

A method for determining a mask pattern to be used on a photo-mask in a photolithographic process is described. During the method, a target pattern that includes at least one continuous feature is provided. Then a mask pattern that includes a plurality of distinct types of regions corresponding to the distinct types of regions of the photo-mask is determined. Note that the mask pattern includes at least two separate features corresponding to at least the one continuous feature. Furthermore, at least the two separate features are separated by a spacing having a length and the spacing overlaps at least a portion of at least the one continuous feature.

Claims

1. A method for determining a mask pattern to be used on a photo-mask in a photolithographic process, wherein the photo-mask has a plurality of distinct types of regions having distinct optical properties, comprising:

providing a target pattern, wherein the target pattern includes at least one continuous feature; and

determining the mask pattern that includes a plurality of distinct types of regions corresponding to the distinct types of regions of the photo-mask, wherein the mask pattern includes at least two separate features corresponding to at least the one continuous feature, at least the two separate features are separated by a spacing having a length, and wherein the spacing overlaps at least a portion of at least the one continuous feature.

2. The method of claim 1, wherein at least the two separate features are associated with an intersection in at least the one continuous feature.

3. The method of claim 1, wherein at least the two separate features at least partially overlap at least the one continuous feature.

4. The method of claim 1, wherein the length is a function of a width of at least a portion of the one continuous feature.

5. The method of claim 1, wherein at least the two separate features are separated by a topological change in the mask pattern.

6. The method of claim 1, wherein the determining includes an optical proximity correction.

7. The method of claim 1, wherein the determining includes calculating a gradient of a function, wherein the function depends on an initial mask pattern and the estimate of a wafer pattern to be printed using the photo-mask in the photo-lithographic process, and wherein the gradient is calculated in accordance with a formula obtained by taking a derivative of the function.

8. The method of claim 7, wherein the estimated wafer pattern is determined using a model of the photo-lithographic process.

9. The method of claim 8, wherein the model of the photo-lithographic process includes a photo-resist model.

10. The method of claim 1, wherein at least the one continuous feature includes a line, an intersection of two or more lines, or a contact.

11. The method of claim 1, wherein the target pattern corresponds to at least a portion of an integrated circuit.

12. The method of claim 1, wherein at least one of at least the two separate features includes one or more partial indentations, and wherein a respective partial indentation of the one or more partial indentations has a pre-determined width.

13. The method of claim 1, wherein at least one or at least the two separate features includes one or more bumps, and wherein a respective bump of the one or more bumps has a pre-determined width.

14. The method of claim 1, wherein the target pattern and the mask pattern include bitmap images.

15. The method of claim 1, wherein the target pattern and the mask pattern include grayscale images.

16. The method of claim 15, wherein the determining is performed at sub-pixel resolution.

17. The method of claim 1, wherein the determining is performed over a range of process conditions in the photo-lithographic process.

18. A computer-program product for use in conjunction with a computer system, the computer-program product comprising a computer-readable storage medium and a computer-program mechanism embedded therein for determining a mask pattern to be used on a photo-mask in a photolithographic process, wherein the photo-mask has a plurality of distinct types of regions having distinct optical properties, the computer-program mechanism including:

instructions for providing a target pattern, wherein the target pattern includes at least one continuous feature; and

instructions for determining the mask pattern that includes a plurality of distinct types of regions corresponding to the distinct types of regions of the photo-mask, wherein the mask pattern includes at least two separate features corresponding to at least the one continuous feature, at least the two separate features are separated by a spacing, and wherein the spacing overlaps at least a portion of at least the one continuous feature.

19. A computer system, comprising:

at least one processor;

at least one memory; and

at least one program module, the program module stored in the memory and configured to be executed by the processor, wherein at least the program module is for determining a mask pattern to be used on a photo-mask in a photolithographic process, wherein the photo-mask has a plurality of distinct types of regions having distinct optical properties, at least the program module including;

instructions for providing a target pattern, wherein the target pattern includes at least one continuous feature; and

instructions for determining the mask pattern that includes a plurality of distinct types of regions corresponding to the distinct types of regions of the photo-mask, wherein the mask pattern includes at least two separate features corresponding to at least the one continuous feature, at least the two separate features are separated by a spacing, and wherein the spacing overlaps at least a portion of at least the one continuous feature.

20. A method for determining a mask pattern to be used on a photo-mask in a photolithographic process, wherein the photo-mask has a plurality of distinct types of regions having distinct optical properties, comprising:

providing a target pattern, wherein the target pattern includes at least one continuous feature; and

determining the mask pattern that includes a plurality of distinct types of regions corresponding to the distinct types of regions of the photo-mask, wherein;

the mask pattern includes at least two separate features corresponding to at least the one continuous feature;

the two separate features represent a first type of region having a first distinct optical property;

each of the two separate features at least partially overlaps a portion of the continuous feature;

the two separate features are separated by a gap that represents a second type of region having a second distinct optical property; and

the gap overlaps at least a portion of the continuous region.

21. A method for determining a write pattern to be used by a write device in a semiconductor-manufacturing process, comprising:

providing a target pattern, wherein the target pattern includes at least one continuous feature; and

determining the write pattern, wherein the write pattern includes instructions for at least two separate features corresponding to at least the one continuous feature, at least the two separate features are separated by a spacing, and wherein the spacing overlaps at least a portion of at least the one continuous feature.

22. A photo-mask for use in a photolithographic process, wherein the photo-mask has a plurality of distinct types of regions having distinct optical properties, and wherein a mask pattern to which the photo-mask corresponds is determined in a process including the operations of:

providing a target pattern, wherein the target pattern includes at least one continuous feature; and

determining the mask pattern that includes a plurality of distinct types of regions corresponding to the distinct types of regions of the photo-mask, wherein the mask pattern includes at least two separate features corresponding to at least the one continuous feature, at least the two separate features are separated by a spacing, and wherein the spacing overlaps at least a portion of at least the one continuous feature.

23. A semiconductor wafer, wherein the semiconductor wafer is produced in a photo-lithographic process that includes a photo-mask, wherein the photo-mask has a plurality of distinct types of regions having distinct optical properties, and wherein a mask pattern to which the photo-mask corresponds is determined in a process including the operations of:

providing a target pattern, wherein the target pattern includes at least one continuous feature; and

determining the mask pattern that includes a plurality of distinct types of regions corresponding to the distinct types of regions of the photo-mask, wherein the mask pattern includes at least two separate features corresponding to at least the one continuous feature, at least the two separate features are separated by a spacing, and wherein the spacing overlaps at least a portion of at least the one continuous feature.

24. A semiconductor wafer, wherein the semiconductor wafer is produced in a semiconductor-manufacturing process that includes a write device using a write pattern, wherein the write pattern is determined in a process including the operations of:

providing a target pattern, wherein the target pattern includes at least one continuous feature; and

determining the write pattern, wherein the write pattern includes instructions for at least two separate features corresponding to at least the one continuous feature, at least the two separate features are separated by a spacing, and wherein the spacing overlaps at least a portion of at least the one continuous feature.

25. A data file stored in a computer-readable medium, comprising:

information corresponding to mask pattern that includes a plurality of distinct types of regions corresponding to the distinct types of regions of a photo-mask that is to print a wafer pattern in a semiconductor-manufacturing process, wherein the mask pattern includes at least two separate features corresponding to at least one continuous feature in a target pattern, at least the two separate features are separated by a spacing, the spacing overlaps at least a portion of at least the one continuous feature, and wherein the wafer pattern is to approximate the target pattern.

26. A data file stored in a computer-readable medium, comprising:

information corresponding to write pattern that is to be used by a write tool in a semiconductor-manufacturing process to print a wafer pattern, wherein the write pattern includes instructions for at least two separate features corresponding to at least one continuous feature in a target pattern, at least the two separate features are separated by a spacing, the spacing overlaps at least a portion of at least the one continuous feature, and wherein the wafer pattern is to approximate the target pattern.