System and method for lithography simulation

• US 8,516,405 B2
• Filed: 06/26/2012
• Issued: 08/20/2013
• Est. Priority Date: 10/07/2003
• Status: Expired due to Fees

• Current Assignee: ASML Netherlands BV (ASML Holding NV)
• Original Assignee: ASML Netherlands BV (ASML Holding NV)
• Inventors: Ye, Jun, Lu, Yen-Wen, Cao, Yu, Chen, Luoqi, Chen, Xun
• Primary Examiner(s): Kik, Phallaka
• Application Number:
  US13/533,942
• Publication Number:
  US 20120269421A1
• Time in Patent Office: 420 Days
• Field of Search: 716/52, 716/53, 716/54, 716/55, 716/112, 716/136, 700/120, 700/121, 430/5, 378/35
• US Class Current: 716/52
• CPC Class Codes: G03F 1/00 Originals for photomechanical production of textured or patterned surfaces, e.g., masks, photo-masks, reticles; Mask blanks or pellicles therefor; Containers specially adapted therefor; Preparation thereof
• CPC Class Codes: G03F 7/004 Photosensitive materials G03F7/12, G03F7/14 take precedence
• CPC Class Codes: G03F 7/705 Modelling or simulating from physical phenomena up to complete wafer processes or whole workflow in wafer productions
• CPC Class Codes: G03F 7/70666 Aerial image, i.e. measuring the image of the patterned exposure light at the image plane of the projection system
• CPC Class Codes: G06F 2119/18 Manufacturability analysis or optimisation for manufacturability
• CPC Class Codes: G06F 30/20 Design optimisation, verification or simulation optimisation, verification or simulation of circuit designs G06F30/30
• CPC Class Codes: G06F 30/333 Design for testability [DFT], e.g. scan chain or built-in self-test [BIST]
• CPC Class Codes: G06F 30/398 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 Class Codes: G06T 2207/30148 Semiconductor; IC; Wafer
• CPC Class Codes: G06T 7/0004 Industrial image inspection
• CPC Class Codes: G16Z 99/00 Subject matter not provided for in other main groups of this subclass
• CPC Class Codes: G21K 5/00 Irradiation devices discharge tubes for irradiating H01J37/00

Abstract

In one aspect, the present invention is directed to a technique of, and system for simulating, verifying, inspecting, characterizing, determining and/or evaluating the lithographic designs, techniques and/or systems, and/or individual functions performed thereby or components used therein. In one embodiment, the present invention is a system and method that accelerates lithography simulation, inspection, characterization and/or evaluation of the optical characteristics and/or properties, as well as the effects and/or interactions of lithographic systems and processing techniques.

Claims

1. A method implemented by a computer, the method comprising:

receiving data corresponding to a first design, the data including a plurality of polygons;

converting, using the computer, the data into a pixel-based representation of the first design;

identifying first and second different potential process window conditions;

processing, using the computer, the pixel-based representation to obtain first and second simulated images respectively corresponding to the first and second potential process window conditions; and

analyzing, using the computer, the first and second simulated images to determine deviations from a target design at the first and second potential process window conditions.

2. A method according to claim 1, wherein processing includes using a model of an imaging path of projection and illumination optics of a photolithographic process for imaging the first design.

3. A method according to claim 2, further comprising determining a critical dimension sensitivity of the first design to a change in at least one process parameter of the photolithographic process.

4. A method according to claim 3, wherein determining the critical dimension sensitivity of the design pattern on the photolithographic mask to the change in the at least one process parameter of the photolithographic process further includes determining a plurality of derivatives as the critical dimension sensitivity of the first design.

5. A method according to claim 3, wherein the change in the at least one process parameter of the photolithographic process is a change in focus, illumination dose, numerical aperture or illumination aperture.

6. A method according to claim 3, wherein analyzing includes determining a configuration of settings of the photolithographic process using a comparison of the first and second simulated images to the target design.

7. A method according to claim 6, wherein the configuration of settings include at least one of focus, illumination dose, numerical aperture or illumination aperture.

8. A method according to claim 2, wherein the model comprises coefficient matrices representing the imaging path of the projection and illumination optics of the photolithographic process.

9. A method according to claim 8, wherein the coefficient matrices are representative of one or more of a focus, dose, numerical aperture, illumination aperture, and aberration of the photolithographic process.

10. A method according to claim 1, further comprising:

receiving data corresponding to a second design, the data including a second plurality of polygons;

converting, using the computer, the data into a pixel-based representation of the second design;

processing, using the computer, the pixel-based representation to obtain third and fourth simulated images respectively corresponding to the first and second potential process window conditions; and

analyzing, using the computer, the third and fourth simulated images to determine deviations from the target design at the first and second potential process window conditions.

11. A method according to claim 10, wherein the second design comprises alterations to the first design.

12. A method according to claim 11, wherein the alterations comprise resolution enhancement techniques (RET).

13. A method according to claim 11, wherein the alterations comprise optical proximity correction (OPC) techniques.

14. A method according to claim 11, wherein the alterations comprise phase shift mask (PSM) techniques.

15. A method according to claim 1, wherein the first and second potential process window conditions comprise different first and second defocus values, respectively.

16. A method according to claim 1, wherein the first and second potential process window conditions comprise different first and second exposure dose values, respectively.

17. A computer program product comprising non-transitory computer-readable storage media bearing instructions which, when executed by a computer, cause the computer to perform a method comprising:

receiving data corresponding to a first design, the data including a plurality of polygons;

converting, using the computer, the data into a pixel-based representation of the first design;

identifying first and second different potential process window conditions;

processing, using the computer, the pixel-based representation to obtain first and second simulated images respectively corresponding to the first and second potential process window conditions; and

analyzing, using the computer, the first and second simulated images to determine deviations from a target design at the first and second potential process window conditions.