Method of forming a capacitor of a semiconductor device

• US 5,985,730 A
• Filed: 06/11/1998
• Issued: 11/16/1999
• Est. Priority Date: 06/11/1997
• Status: Expired due to Term

• Current Assignee: Hyundai Electronics Industries Co. Ltd. (SK Hynix Inc.)
• Original Assignee: Hyundai Electronics Industries Co. Ltd. (SK Hynix Inc.)
• Inventors: Lim, Chan
• Primary Examiner(s): Nguyen, Tuan H.
• Application Number:
  US09/095,696
• Time in Patent Office: 523 Days
• Field of Search: 439/393, 439/3, 439/240, 439/795, 439/250, 439/253, 439/396
• US Class Current: 438/393
• CPC Class Codes: H01L 28/40 Capacitors

Abstract

The present invention relates to a method of forming a capacitor of a semiconductor device, which specially treats the surface of a charge storage electrode of the lower in order to improve the poor stepcoverage of the Ta₂ O₅ film deposited by the PECVD method in the capacitor using the Ta₂ O₅ film having a specific dielectric constant as the dielectric film, prevents the leakage current from generating according to improving the electrical characteristic of the capacitor by depositing the Ta₂ O₅ film by use of the LPCVD method where the stepcoverage is excellent, and improves the characteristic of the semiconductor device and the trust according to the result.

Claims

1. A method of forming a capacitor of a semiconductor device comprising steps of:

providing a semiconductor substrate;

forming a charge storage electrode on the top of said semiconductor substrate;

nitrifying an entire surface of said charge storage electrode;

plasma-treating and oxidizing a surface of said nitrified charge storage electrode;

depositing a Ta₂ O₅ film on said charge storage electrode surface by LPCVD method and plasma treating a Ta₂ O₅ film, wherein the process of depositing and plasma treating of a Ta₂ O₅ film is carried out at least one if not more times;

thermally treating said Ta₂ O₅ film; and

forming a plate electrode on the top of said entire surface.

2. The method according to claim 1, wherein said nitrifying process of said charge storage electrode is carried out at a temperature of 800.sup.˜

900°

C. for 40.sup.˜

100 secs. by RTN method.

3. The method according to claim 1, wherein a surface of said nitrified charge storage electrode is oxidized under a temperature of 150.sup.˜

450°

C. using an excited plasma gas, N₂ O or O₂.

4. The method according to claim 1, wherein said surface of said nitrified charge storage electrode is oxidized by a dry or wet oxidizing method, using vapor, H₂ O or O₂.

5. The method according to claim 1, wherein said plasma treating process of said Ta₂ O₅ film is carried out at the temperature of 150.sup.˜

450°

C. by use of a gas, N₂ O or O₂ or a gas UV-O₃ activated by ultraviolet.

6. The method according to claim 1, wherein the thermal treating process of said Ta₂ O₅ film is carried out at the temperature 700.sup.˜

820°

C. with a gas atmosphere of N₂ O or O₂ and thereby said Ta₂ O₅ film is polycrystalized.

7. A method of forming a capacitor of a semiconductor device comprising steps of:

providing a semiconductor substrate;

forming a charge storage electrode on the top of said semiconductor substrate;

nitrifying an entire surface of said charge storage electrode;

plasma-treating and oxidizing a surface of said nitrified charge storage electrode;

depositing a Ta₂ O₅ film on said charge storage electrode surface by the LPCVD method;

plasma-treating said Ta₂ O₅ film;

thermally treating said Ta₂ O₅ film; and

forming a plate electrode on the top of said entire surface.

8. The method according to claim 7, wherein said nitrifying process of said charge storage electrode is carried out at a temperature of 800.sup.˜

900°

C. for 40.sup.˜

100 secs. by RTN method.

9. The method according to claim 7, wherein a surface of said nitrified charge storage electrode is oxidized under a temperature of 150.sup.˜

450°

C., using an excited plasma gas, N₂ O or O₂, or by a dry or wet oxidizing method, using vapor, H₂ O or O₂.

10. The method according to claim 7, wherein said oxidation process of said nitrified charge storage electrode surface is carried out by a step of depositing the remaining portion of said Ta₂ O₅ film by the LPCVD method after depositing a portion of said Ta₂ O₅ film by the PECVD method.

11. The method according to claim 10, wherein said process of depositing said Ta₂ O₅ film by said PECVD method is carried out at a temperature of 350.sup.˜

450°

C. and pressure of 1m Torr .sup.˜

9 Torr by use of a gas, N₂ O or O₂ or a material Ta(OC₂ H₅)₅ and said Ta₂ O₅ film has a thickness of 5.sup.˜

50 Å

.

12. The method according to claim 7, wherein said plasma treating process of said Ta₂ O₅ film is carried out at a temperature of 150.sup.˜

450°

C. by use of a gas, N₂ O or O₂, or a gas UV-O₃ activated by ultraviolet.

13. The method according to claim 7, wherein a thermal treating process of said Ta₂ O₅ film is carried out at a temperature of 700.sup.˜

820°

C. with a gas atmosphere of N₂ O or O₂ and said Ta₂ O₅ film is polycrystalized.

14. A method of forming a capacitor of a semiconductor device comprising steps of:

providing a semiconductor substrate;

forming a charge storage electrode on the top of said semiconductor substrate;

removing a natural oxide film from the top of said charge storage electrode;

nitrifying an surface of said structure;

plasma-treating said nitrified surface;

depositing a portion of a first Ta₂ O₅ film on said structure surface by the LPCVD method;

plasma-treating said first Ta₂ O₅ film;

depositing a second Ta₂ O₅ film on said structure surface by the LPCVD method;

plasma-treating and thermally treating said first and second Ta₂ O₅ film; and

forming a plate electrode on top of said entire surface.

15. The method according to claim 14, wherein said nitrifying process of said charge storage electrode is carried out using RTN method.

16. The method according to claim 14, wherein said first Ta₂ O₅ film is deposited with a thickness of 50.sup.˜

70 Å

.

17. The method according to claim 14, wherein said first and second Ta₂ O₅ film is deposited in an amorphous state.

18. The method according to claim 14, wherein said plasma treating process is carried out for 1.sup.˜

20 mins. at a temperature of 130.sup.˜

450°

C. and power of 100.sup.˜

300 w.

19. The method according to claim 14, wherein said thermal treating process is carried out for 5.sup.˜

30 mins. at a temperature of 750.sup.˜

820°

C. under a gas atmosphere of O₂, or for 70.sup.˜

80 secs. at a temperature of 800.sup.˜

900°

C. under a gas atmosphere of O₂ or N₂ O.

20. The method according to claim 14, wherein the thickness of said first Ta₂ O₅ film is deposited with a thickness of 40.sup.˜

50 Å

without plasma- treating said nitrified surface.