Fine Treatment Agent and Fine Treatment Method Using Same

• US 20080029487A1
• Filed: 12/19/2005
• Published: 02/07/2008
• Est. Priority Date: 12/20/2004
• Status: Active Grant

• Current Assignee: Stella Chemifa Corporation
• Original Assignee: Stella Chemifa Corporation
• Inventors: Tsurumaru, Hitoshi, Hasebe, Rui, Nakashima, Hideki, Kikuyama, Hirohisa, Nii, Keiichi, Kujime, Takanobu, Ito, Kanenori, Waki, Masahide
• Granted Patent: US 7,727,415 B2
• Time in Patent Office: Days
• US Class Current: 216/99
• CPC Class Codes: C23F 1/26 for etching refractory metals
• CPC Class Codes: H01L 21/32134 by liquid etching only
• CPC Class Codes: H01L 27/124 with a particular composition, shape or layout of the wiring layers specially adapted to the circuit arrangement, e.g. scanning lines in LCD pixel circuits wiring structures per se H01L23/52

Abstract

A fine treatment agent according to the present invention is a fine treatment agent for the fine treatment of a multilayer film, including a tungsten film and a silicon oxide film comprising at least one from among hydrogen fluoride, nitric acid, ammonium fluoride and ammonium chloride. Thus, a fine treatment agent which makes fine treatment on a multilayer film, including a tungsten film and a silicon oxide film, possible by controlling the etching rate and a fine treatment method using the same can be provided.

Claims

1. A fine treatment agent, which is used for the fine processing of a multilayer film including a tungsten containing film and a silicon compound containing film, comprising

hydrogen fluoride, nitric acid and at least one of ammonium fluoride or ammonium chloride.

2. The fine treatment agent according to claim 1, which has an etching rate for said tungsten containing film at 25°

C. which is within a range from 0.5 nm/min to 5000 nm/min and an etching rate for said silicon compound containing film at 25°

C. which is within a range from 0.5 times to 2 times the etching rate for said tungsten containing film at 25°

C.

3. The fine treatment agent according to claim 2, wherein X, Y and Z satisfy the following relational expressions when the content of said hydrogen fluoride is X mol/kg, the content of the nitric acid is Y mol/kg and the content of at least one of the ammonium fluoride or the ammonium chloride is Z mol/kg;

[Formula 1]

Z≦

1.25Y−

1.75 

 

(1)
Z>

1.4Y−

3 

 

(2)
Z≦

−

0.973Y+0.108×

(100−

4X) 

 

(3)
0.5≦

X≦

10, Y>

0, 0<

Z≦

6 

 

(4).

4. The fine treatment agent according to claim 1, which has an etching rate for said tungsten containing film at 25°

C. which is within a range from 0.5 nm/min to 5000 nm/min and an etching rate for said silicon compound containing film at 25°

C. which is either less than 0.5 times or greater than 2 times the etching rate for said tungsten containing film at 25°

C.

5. The fine treatment agent according to claim 4, wherein X, Y and Z satisfy the following relational expressions when the content of said hydrogen fluoride is X mol/kg, the content of the nitric acid is Y mol/kg and the content of at least one of the ammonium fluoride or the ammonium chloride is Z mol/kg;

[Formula 2]

Z≦

−

0.973Y+0.108×

(100−

4X) 

 

(3)
0.5≦

X≦

10, Y>

0, 0<

Z≦

6 

 

(4)
Z≦

1.4Y−

3 

 

(5).

6. The fine treatment agent according to claim 1, wherein a main component of said tungsten containing film is at least one type selected from the group consisting of tungsten, titanium tungsten, copper tungsten, nickel tungsten, cobalt tungsten, molybdenum tungsten, tungsten silicide and tungsten nitride.

7. The fine treatment agent according to claim 1, wherein said silicon compound containing film is a single layer of one type selected from the group consisting of a silicon thermal oxide film, a non-doped silicate glass film, a phosphorous doped silicate glass film, a boron doped silicate glass film, a phosphorous and boron doped silicate glass film, a TEOS film, a fluorine containing silicon oxide film, a carbon containing silicon oxide film, a silicon nitride oxide film and a natural oxide film, or a multilayer film of two or more types selected from the group.

8. The fine treatment agent according to claim 1, wherein the etching rate for said silicon compound containing film at 25°

C. is within a range from 0.5 nm/min to 5000 nm/min.

9. The fine treatment agent according to claim 1, further containing 0.001 weight percent to 0.1 weight percent of a surfactant.

10. A fine treatment method comprising:

providing the fine treatment agent according to claim 1;

and finely processing at least one of a tungsten containing film or a silicon compound containing film by using the fine treatment agent as an etchant.

11. The fine treatment agent according to claim 1, which contains metal elements in an amount of no more than 1 ppb.

12. The fine treatment method according to claim 10, wherein both the tungsten containing film and the silicon compound containing film are finely processed at the same time using as an etchant the fine treatment agent having an etching rate for the tungsten containing film at 25°

C. which is within a range from 0.5 nm/min to 5000 nm/min and an etching rate for the silicon compound containing film at 25°

C. which is within a range from 0.5 times to 2 times the etching rate for the tungsten containing film at 25°

C.

13. The fine treatment method according to claim 10, wherein one of the tungsten containing film or the silicon compound containing film is predominantly finely processed using as an etchant the fine treatment agent having an etching rate for the tungsten containing film at 25°

C. which is within a range from 0.5 nm/min to 5000 nm/min and an etching rate for the silicon compound containing film at 25°

C. which is less than 0.5 times or more than 2 times the etching rate for the tungsten containing film at 25°

C.

14. The fine treatment method according to claim 10, wherein the processing step is conducted at a temperature of 5°

C. to 50°

C.