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

Patent metadata

Field	Value
Publication number	US-2022084829-A1
Application number	US-202117393601-A
Country	US
Kind code	A1
Filing date	Aug 4, 2021
Priority date	Sep 11, 2020
Publication date	Mar 17, 2022
Grant date	—

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, and a trench penetrating the first oxide film, the nitride film, and the second oxide film is formed; chamfering the oxide films 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.

2 . The method of claim 1 , wherein the first plasma process uses a fluorine-containing radical.

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

4 . The method of claim 1 , wherein a selection ratio of the nitride film to the oxide film is a first selection ratio in the first plasma process,
wherein a selection ratio of the nitride film to the oxide film is a second selection ratio greater than the first selection ratio in the second plasma process.

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

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

7 . A method for fabricating a semiconductor device comprising:
providing a substrate, in which an insulating film structure including a plurality of oxide films and a plurality of nitride films alternately stacked, a vertical structure penetrating the insulating film structure and including a charge storage film for storing data, and a trench penetrating the insulating film structure are formed; chamfering the plurality of oxide films exposed by the trench while removing a part of the plurality of nitride films exposed by the trench by using a first plasma process; removing a plurality of nitride films left after the first plasma process to form a gate formation region exposing a part of the vertical structure by using a second plasma process; and filling a metal in the gate formation region so as to be electrically connected to the vertical structure.

8 . The method of claim 7 , wherein the first plasma process uses a fluorine-containing radical.

9 . The method of claim 7 , wherein the second plasma process uses a nitrogen-containing radical and an oxygen-containing radical.

10 . The method of claim 7 , wherein a selection ratio of the nitride film to the oxide film is a first selection ratio in the first plasma process,
wherein a selection ratio of the nitride film to the oxide film is a second selection ratio greater than the first selection ratio in the second plasma process.

11 . An apparatus for processing a substrate comprising:
a first space disposed between an electrode and an ion blocker; a second space disposed between the ion blocker and a shower head; a processing space for processing a substrate under the shower head; and a support module disposed in the processing space and for supporting a substrate, wherein 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, is located on the support module, wherein a fluorine-containing gas is provided in the first space to generate a first plasma, wherein the first plasma is provided to the processing space through the ion blocker and the shower head so that a part of the plurality of nitride films exposed by the trench are removed while chamfering a plurality of exposed oxide films.

12 . The apparatus of claim 11 , wherein nitrogen and hydrogen-containing gas is provided in the processing space,
wherein the first plasma is filtered by the ion blocker and provided to the processing space through the shower head, and mixed with the nitrogen and hydrogen-containing gas to generate a first etchant, wherein a part of the plurality of nitride films exposed by the trench is removed while chamfering the plurality of exposed oxide films by the first etchant.

13 . The apparatus of claim 12 , wherein the nitrogen and hydrogen-containing gas is provided through the ion blocker or the shower head.

14 . The apparatus of claim 11 , wherein after chamfering the plurality of oxide films, a nitrogen-containing gas and a first oxygen-containing gas are provided in the first space to generate a second plasma, and a remaining part of the nitride film is removed by the second plasma.

15 . The apparatus of claim 14 , wherein a second oxygen-containing gas is provided in the processing space,
wherein the second plasma is filtered by the ion blocker and provided to the processing space through the shower head, and mixed with the second oxygen-containing gas to generate a second etchant, wherein a remaining part of the nitride film is removed by the second etchant.

16 . The apparatus of claim 11 , wherein a temperature of the processing space is 10 to 100° C., and a pressure of the processing space is 650 to 850 mTorr.

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

• H10D30/0413

  of FETs having charge-trapping gate insulators, e.g. MNOS transistors · CPC title