Method for fabricating semiconductor device and apparatus for processing substrate using plasma

Patent metadata

Field	Value
Publication number	US-12451358-B2
Application number	US-202117393601-A
Country	US
Kind code	B2
Filing date	Aug 4, 2021
Priority date	Sep 11, 2020
Publication date	Oct 21, 2025
Grant date	Oct 21, 2025

Abstract

A method of fabricating a semiconductor device with improved electrical characteristics and reliability is provided. The method of fabricating the semiconductor device includes providing a substrate, in which a first oxide film, a nitride film, and a second oxide film are sequentially stacked, and a trench penetrating the first oxide film, the nitride film, and the second oxide film is formed, chamfering the oxide film exposed by the trench while removing a part of the nitride film exposed by the trench by using a first plasma process, and removing the nitride film left after the first plasma process by using a second plasma process.

First claim

What is claimed is:

1. A method for fabricating a semiconductor device comprising:
providing a substrate, in which a first oxide film, a nitride film, and a second oxide film are sequentially stacked, the substrate further comprising a trench penetrating the first oxide film, the nitride film, and the second oxide film in a thickness direction perpendicular to an upper surface of the substrate;
chamfering the first and second oxide films exposed by the trench to reduce the thickness of ends of the first and second oxide films while removing a part of the nitride film exposed by the trench by using a first plasma process, wherein the first plasma process uses a fluorine-containing radical; and
removing a portion of the nitride film left after the first plasma process by using a second plasma process,
wherein a selection ratio of the nitride film to the first and second oxide films is a first selection ratio in the first plasma process,
wherein a selection ratio of the nitride film to the first and second oxide films is a second selection ratio greater than the first selection ratio in the second plasma process.

2. The method of claim 1 , wherein the second plasma process uses first and second radicals, the first radical being a nitrogen-containing radical and the second radical being an oxygen-containing radical.

3. The method of claim 1 , further comprising filling a space, from which the nitride film has been removed, with a metal.

4. The method of claim 1 , wherein the first plasma process and the second plasma process are performed in-situ.

5. The method of claim 1 , wherein the chamfering is performed after formation of the trench penetrating the first oxide film, the nitride film, and the second oxide film in the thickness direction.

Assignees

• Semes Co Ltd

Inventors

• Koo Joun Taek
• Lee Seong Gil
• Park Wan Jae
• Um Young Je
• Kim Dong Hun
• Lee Ji Hwan
• Oh Dong Sub
• Noh Myoung Sub
• Kim Du Ri

Classifications

• H10P72/0421

  for drying etching · CPC title

• H10P50/242 Primary

  of Group IV materials · CPC title

• H10D64/013 Primary

  of electrodes having a conductor capacitively coupled to a semiconductor by an insulator · CPC title

• H10P50/283 Primary

  by chemical means · CPC title

• H10B43/27

  the channels comprising vertical portions, e.g. U-shaped channels · CPC title