Cleaning method of semiconductor structure

Patent metadata

Field	Value
Publication number	US-2022199394-A1
Application number	US-202117645302-A
Country	US
Kind code	A1
Filing date	Dec 20, 2021
Priority date	Dec 21, 2020
Publication date	Jun 23, 2022
Grant date	—

Abstract

A cleaning method of a semiconductor structure is provided. The method includes providing a substrate, where the substrate includes a functional surface and a back surface that is opposite to the functional surface. The method also includes forming a fluid passivation film on the functional surface of the substrate. In addition, the method includes after forming the fluid passivation film, performing a first charge removal treatment on the functional surface of the substrate through a wet cleaning process. Further, the method includes after performing the first charge removal treatment, performing a main cleaning treatment on the functional surface and the back surface of the substrate.

First claim

What is claimed is:

1 . A cleaning method of a semiconductor structure, comprising:
providing a substrate, wherein the substrate comprises a functional surface and a back surface that is opposite to the functional surface; forming a fluid passivation film on the functional surface of the substrate; after forming the fluid passivation film, performing a first charge removal treatment on the functional surface of the substrate through a wet cleaning process; and after performing the first charge removal treatment, performing a main cleaning treatment on the functional surface and the back surface of the substrate.

2 . The cleaning method according to claim 1 , wherein:
the fluid passivation film is made of a material comprising liquid, wherein the liquid comprises pure water or isopropanol.

3 . The cleaning method according to claim 2 , wherein:
forming the fluid passivation film comprises a spray process, wherein process parameters of the spray process comprise: a rotation speed in a range of approximately 0-1200 rpm, a flow rate in a range of approximately 0-2000 sccm, and a time period in a range of approximately 0-5 minutes.

4 . The cleaning method according to claim 1 , wherein:
the wet cleaning process comprises a first stage, and a second stage after the first stage, in the first stage, a liquid film of a solution of the wet cleaning process covers a surface of the fluid passivation film, and in the second stage, the liquid film of the solution of the wet cleaning process and the fluid passivation film are inter-soluble, to form a mixed solution film, wherein the mixed solution film is located on the functional surface of the substrate.

5 . The cleaning method according to claim 4 , wherein:
a ratio of a thickness of the fluid passivation film over a thickness of the liquid film is in a range of approximately 0-5:1.

6 . The cleaning method according to claim 5 , wherein:
the thickness of the fluid passivation film is in a range of approximately 0-5 mm.

7 . The cleaning method according to claim 5 , wherein:
the thickness of the liquid film is in a range of approximately 0-5 mm.

8 . The cleaning method according to claim 4 , wherein:
the solution of the wet cleaning process comprises a deionized aqueous solution containing carbon dioxide dissolved therein, wherein parameters of the wet cleaning process comprise: a PH value of the solution in a range of approximately 4-7, an electrical conductivity of the solution in a range of approximately 0-50 μS/cm, a flow rate of the solution in a range of approximately 0-2000 sccm, a time period in a range of approximately 0-5 minutes, and a rotation speed in a range of approximately 0-1200 rpm.

9 . The cleaning method according to claim 4 , wherein:
the mixed solution film comprises a deionized aqueous solution containing carbon dioxide dissolved therein, wherein a solution of the mixed solution film has a PH value in a range of approximately 4-7, and an electrical conductivity in a range of approximately 0-40 μS/cm.

10 . The cleaning method according to claim 4 , wherein:
the solution of the wet cleaning process comprises a deionized aqueous solution containing ammonia dissolved therein, wherein parameters of the wet cleaning process comprise: a PH value of the solution in a range of approximately 7-11, an electrical conductivity of the solution in a range of approximately 0-50 μS/cm, a flow rate of the solution in a range of approximately 0-2000 sccm, a time period in a range of approximately 0-5 minutes, and a rotation speed in a range of approximately 0-1200 rpm.

11 . The cleaning method according to claim 4 , wherein:
the mixed solution film comprises a deionized aqueous solution containing ammonia dissolved therein, wherein a solution of the mixed solution film has a PH value in a range of approximately 7-11, and an electrical conductivity in a range of approximately 0-40 μS/cm.

12 . The cleaning method according to claim 1 , wherein:
a solution of the main cleaning treatment performed on the functional surface and the back surface of the substrate comprises an acidic solution or an alkaline solution.

13 . The cleaning method according to claim 1 , wherein:
the substrate comprises a base and a fin structure over the base, wherein a surface of the fin structure is the functional surface of the substrate.

14 . The cleaning method according to claim 1 , wherein:
the substrate comprises a base, and a device layer over the base, wherein: a surface of the device layer is the functional surface of the substrate, the device layer comprises an isolation structure and a device structure located in the isolation structure, and the device structure comprises at least one of a transistor, a diode, a triode, a capacitor, an inductor, and a conductive structure.

15 . The cleaning method according to claim 14 , wherein:
the substrate further comprises a dielectric layer located over the device layer, and a conductive layer located in the dielectric layer, wherein the conductive layer is electrically connected to the device structure, and a surface of the conductive layer is the functional surface of the substrate.

16 . The cleaning method according to claim 1 , before forming the fluid passivation film on the functional surface of the substrate, further comprising:
performing a second charge removal treatment on the back surface of the substrate.

17 . The cleaning method according to claim 16 , wherein:
the second charge removal treatment performed on the back surface of the substrate comprises a wet cleaning process, wherein a solution of the wet cleaning process comprises a deionized aqueous solution containing carbon dioxide dissolved therein or a deionized aqueous solution containing ammonia dissolved therein.

Assignees

• Semiconductor Mfg Int Shanghai Corp
• Semiconductor Mfg Int Beijing Corp

Inventors

• Zhang Jing

Classifications

• H10P70/15 Primary

  by wet cleaning only (H10P70/52 takes precedence) · CPC title

• H10P70/56

  Cleaning of wafer backside · CPC title

• H10P70/23

  during, before or after processing of insulating materials · CPC title

• H10P70/20 Primary

  Cleaning during device manufacture · CPC title

• C01C1/024

  Purification · CPC title