# US 11,079,670 B2 · Manufacturing method of phase shift mask and phase shift mask

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

- Number: US 11,079,670 B2
- Document ID: US11079670B2
- Status: Granted
- Kind: B2
- Application number: 16/334,870
- Filed: 2018-09-21
- Published: 2020-06-04
- Granted: 2021-08-03
- Earliest claimed: 2018-02-11
- Assignees: Beijing Boe Display Technology Co., Ltd.; Boe Technology Group Co., Ltd.
- Applicants: Beijing BOE Display Technology Co., Ltd.; BOE Technology Group Co., Ltd.
- Inventors: Mingxuan Liu; Huibin Guo; Yongzhi Song; Xiaoxiang Zhang; Wenqing Xu; Zumou Wu; Xiaolong Li
- Web page: https://patentgrep.com/patent/US11079670B2

## CPC

- G03F 1/26: Phase shift masks [PSM]; PSM blanks; 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

Disclosed are a manufacturing method of a phase shift mask and a phase shift mask. The manufacturing method of a phase shift mask includes: forming a pattern of metal shielding layer on a base substrate; forming a phase shift layer and a first photoresist layer in sequence on the pattern of metal shielding layer; patterning the first photoresist layer with the pattern of metal shielding layer serving as a mask to form a pattern of first photoresist layer; and etching the phase shift layer with the pattern of first photoresist layer serving as a mask to form a pattern of phase shift layer.

## Claims

### Claim 1

A manufacturing method of a phase shift mask, comprising:
forming a pattern of metal shielding layer on a base substrate;
forming a phase shift layer and a first photoresist layer in sequence on the pattern of metal shielding layer;
patterning the first photoresist layer with the pattern of metal shielding layer serving as a mask to form a pattern of first photoresist layer in such a way that an orthographic projection of the pattern of first photoresist layer on the base substrate completely covers an orthographic projection of the pattern of metal shielding layer on the base substrate and an area of the orthographic projection of the pattern of first photoresist layer on the base substrate is larger than an area of the orthographic projection of the pattern of metal shielding layer on the base substrate; and
etching the phase shift layer with the pattern of first photoresist layer serving as a mask to form a pattern of phase shift layer,
wherein patterning the first photoresist layer with the pattern of metal shielding layer serving as the mask to form the pattern of first photoresist layer comprises:
enabling at least a portion of light emitted from an exposure machine located at a side of the base substrate facing away from the pattern of metal shielding layer to be transmitted through the phase shift layer having a light transmitting property, with shielding by the pattern of metal shielding layer, such that the first photoresist layer is exposed to form the pattern of first photoresist layer.

### Claim 2 (depends on 1)

The manufacturing method of claim 1, wherein exposing the first photoresist layer comprises:
under-exposing the first photoresist layer such that an orthographic projection of the pattern of first photoresist layer on the base substrate completely covers an orthographic projection of the pattern of metal shielding layer on the base substrate and an area of the orthographic projection of the pattern of first photoresist layer on the base substrate is larger than an area of the orthographic projection of the pattern of metal shielding layer on the base substrate.

### Claim 3 (depends on 2)

The manufacturing method of claim 2, wherein etching the phase shift layer with the pattern of first photoresist layer serving as the mask to form the pattern of phase shift layer comprises:
etching the phase shift layer with the pattern of first photoresist layer serving as the mask to form the pattern of phase shift layer in such a way that an orthographic projection of the pattern of phase shift layer on the base substrate completely covers the orthographic projection of the pattern of metal shielding layer on the base substrate and an area of the orthographic projection of the pattern of phase shift layer on the base substrate is larger than the area of the orthographic projection of the pattern of metal shielding layer on the base substrate.

### Claim 4 (depends on 1)

The manufacturing method of claim 1, wherein forming the pattern of metal shielding layer on the base substrate comprises:
forming a metal shielding layer and a second photoresist layer in sequence on the base substrate;
patterning the second photoresist layer to form a pattern of second photoresist layer;
etching the metal shielding layer with the pattern of second photoresist layer serving as a mask to form the pattern of metal shielding layer; and
removing the pattern of second photoresist layer.

### Claim 5 (depends on 4)

The manufacturing method of claim 4, wherein patterning the second photoresist layer to form the pattern of second photoresist layer comprises:
drawing and patterning the second photoresist layer by using a drawing machine to form the pattern of second photoresist layer.

### Claim 6 (depends on 1)

The manufacturing method of claim 1, further comprising: after forming the pattern of phase shift layer, removing the pattern of first photoresist layer.