Manufacturing method of phase shift mask and phase shift mask

Patent metadata

Field	Value
Publication number	US-2020174359-A1
Application number	US-201816334870-A
Country	US
Kind code	A1
Filing date	Sep 21, 2018
Priority date	Feb 11, 2018
Publication date	Jun 4, 2020
Grant date	—

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.

First 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.

2 . The manufacturing method of claim 1 , 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.

3 . The manufacturing method of claim 2 , 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.

4 . The manufacturing method of claim 3 , 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.

5 . 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.

6 . The manufacturing method of claim 5 , 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.

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

8 . A phase shift mask, wherein the phase shift mask is manufactured by the manufacturing method of claim 1 .

9 . A phase shift mask, comprising:
a base substrate; a pattern of metal shielding layer on the base substrate; and a pattern of phase shift layer covering the pattern of metal shielding layer, wherein an orthographic projection of the pattern of phase shift 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 phase shift 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 widths of the orthographic projection of the pattern of phase shift layer on the base substrate extending beyond the pattern of metal shielding layer on both opposite sides of the pattern of metal shielding layer are identical to each other.

10 . The phase shift mask of claim 9 , wherein the widths of the orthographic projection of the pattern of phase shift layer on the base substrate extending beyond the pattern of metal shielding layer on both opposite sides of the pattern of metal shielding layer are in a range from 0.3 μm to 1 μm, respectively.

11 . The phase shift mask of claim 9 , wherein a material of the pattern of metal shielding layer comprises chromium.

12 . The phase shift mask of claim 9 , wherein a material of the pattern of phase shift layer comprises chromium oxide or molybdenum oxide.

13 . The phase shift mask of claim 10 , wherein a material of the pattern of metal shielding layer comprises chromium.

14 . The phase shift mask of claim 10 , wherein a material of the pattern of phase shift layer comprises chromium oxide or molybdenum oxide.

Assignees

• Beijing Boe Display Tech Co
• Boe Technology Group Co Ltd

Inventors

• Liu Mingxuan
• Guo Huibin
• Song Yongzhi
• Zhang Xiaoxiang
• Xu Wenqing
• Wu Zumou
• Li Xiaolong

Classifications

• G03F1/26 Primary

  Phase shift masks [PSM]; PSM blanks; Preparation thereof · CPC title