# US 2024/0201577 A1 · Method and system for reticle enhancement technology

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 2024/0201577 A1
- Document ID: US20240201577A1
- Status: Published application
- Kind: A1
- Application number: 18/427,577
- Filed: 2024-01-30
- Published: 2024-06-20
- Earliest claimed: 2022-01-28
- Assignees: D2S, Inc.
- Applicants: D2S, Inc.
- Inventors: Akira Fujimura; Nagesh Shirali; Ajay Baranwal
- Web page: https://patentgrep.com/patent/US20240201577A1

## CPC

- G03F 1/36: Masks having proximity correction features; Preparation thereof, e.g. optical proximity correction [OPC] design processes
- G03F 1/70: Adapting basic layout or design of masks to lithographic process requirements, e.g., second iteration correction of mask patterns for imaging
- G03F 7/70441: {Optical proximity correction [OPC]}
- G03F 7/705: {Modelling or simulating from physical phenomena up to complete wafer processes or whole workflow in wafer productions}
- G03F 1/22: Masks or mask blanks for imaging by radiation of 100nm or shorter wavelength, e.g. X-ray masks, extreme ultraviolet [EUV] masks; Preparation thereof
- G03F: PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR; (phototypographic composing devices B41B; photosensitive materials or processes for photographic purposes G03C; electrophotography, sensitive layers or processes therefor G03G)

## Abstract

Methods incorporate variable side wall angle (VSA) into calculated patterns, using a mask 3D (M3D) effect. Embodiments include inputting a mask exposure information and determining the M3D effect. Determining the M3D effect may include determining the VSA. Embodiments may include calculating a VSA; and calculating a pattern on a substrate using the calculated VSA, wherein calculating the pattern on the substrate includes a mask 3D effect.

## Claims

### Claim 1

A method for reticle enhancement technology (RET) for transferring a pattern to a substrate, the method comprising:
inputting a mask exposure information;
determining a mask 3D (M3D) effect, wherein the determining the M3D effect includes determining a variable side wall angle (VSA);
calculating a calculated pattern on the substrate using the M3D effect; and
modifying the mask exposure information based on the calculated pattern on the substrate.

### Claim 2 (depends on 1)

The method of claim 1, wherein the determining the M3D effect uses a neural network.

### Claim 3 (depends on 2)

The method of claim 2, wherein the determining the M3D effect uses a transfer function.

### Claim 4 (depends on 1)

The method of claim 1, wherein the calculating the calculated pattern on the substrate includes lithography simulation.

### Claim 5 (depends on 1)

The method of claim 1, further comprising calculating a mask 2D (M2D) effect from the mask exposure information, wherein the determining the M3D effect is inferenced from the M2D effect.

### Claim 6 (depends on 5)

The method of claim 5, further comprising iterating: 1) the calculating the M2D effect, 2) the determining the M3D effect, 3) the calculating the calculated pattern and 4) the modifying the mask exposure information.

### Claim 7 (depends on 5)

The method of claim 5, wherein the M2D effect further comprises optical proximity correction (OPC).

### Claim 8 (depends on 1)

The method of claim 1, further comprising:
inputting a target substrate pattern; and
calculating the mask exposure information from the target substrate pattern using reticle enhancement technology (RET) prior to inputting the mask exposure information.

### Claim 9 (depends on 8)

The method of claim 8, wherein the RET comprises inverse lithography technology (ILT).

### Claim 10 (depends on 1)

The method of claim 1, wherein the calculating of the calculated pattern on the substrate comprises extreme ultraviolet (EUV) simulation.

### Claim 11 (depends on 1)

The method of claim 1, wherein the determining the M3D effect includes calculating a dose margin from the mask exposure information.

### Claim 12 (depends on 1)

The method of claim 1, wherein the mask exposure information is for a multi-beam exposure system.

### Claim 13

A method for calculating a pattern to be formed on a substrate using optical lithography with a mask, the method comprising:
inputting a mask exposure information that will form a mask pattern on the mask;
calculating a variable side wall angle (VSA);
calculating the pattern on the substrate using the VSA, wherein the calculating the pattern on the substrate includes a mask 3D (M3D) effect; and
modifying the mask exposure information based on the calculated pattern on the substrate.

### Claim 14 (depends on 13)

The method of claim 13, wherein the variable side wall angle is calculated using a neural network.

### Claim 15 (depends on 13)

The method of claim 13, wherein the calculating the pattern on the substrate comprises lithography simulation.

### Claim 16 (depends on 13)

The method of claim 13, wherein the calculating the pattern on the substrate comprises extreme ultraviolet (EUV) simulation.

### Claim 17 (depends on 13)

The method of claim 13, wherein the pattern on the substrate is for a semiconductor device.

### Claim 18 (depends on 13)

The method of claim 13, further comprising calculating the mask pattern from the mask exposure information, wherein the calculating the pattern on the substrate uses the mask pattern.

### Claim 19 (depends on 13)

The method of claim 13, further comprising determining a dose margin from the mask exposure information, wherein the calculating the VSA uses the dose margin.

### Claim 20

A system for reticle enhancement technology (RET) comprising:
a. a device configured to receive a mask exposure information;
b. a device configured to determine a mask 3D (M3D) effect, wherein the determining the M3D effect includes determining a variable side wall angle (VSA); and
c. a device configured to calculate a calculated pattern on a substrate using the M3D effect.

### Claim 21 (depends on 20)

The system of claim 20, further comprising a device configured to calculate a mask 2D (M2D) effect from the mask exposure information, wherein the determining the M3D effect uses the M2D effect.

### Claim 22 (depends on 20)

The system of claim 20, wherein the device configured to determine the M3D effect uses a neural network.