Submerged plasma generator, method of generating plasma in liquid and method of decomposing toxic substance with plasma in liquid

• US 7,067,204 B2
• Filed: 03/31/2003
• Issued: 06/27/2006
• Est. Priority Date: 04/01/2002
• Status: Active Grant

• Current Assignee: Growth, Inc.
• Original Assignee: National University Corporation Ehime University
• Inventors: Nomura, Shinfuku, Hiromichi, Toyota
• Primary Examiner(s): Turner, Archene
• Application Number:
  US10/507,919
• Publication Number:
  US 20050227115A1
• Time in Patent Office: 1,184 Days
• Field of Search: 428/698, 422/156, 422/292, 422/305, 427/430.1, 427/445, 204/157.42, 204/157.46, 204/489, 204/490
• US Class Current: 428/698
• CPC Class Codes: A62D 2101/22 containing halogen
• CPC Class Codes: A62D 2101/28 containing oxygen, sulfur, selenium or tellurium, i.e. chalcogen
• CPC Class Codes: A62D 2203/10 Apparatus specially adapted for treating harmful chemical agents; Details thereof
• CPC Class Codes: A62D 3/13 to sonic energy
• CPC Class Codes: A62D 3/17 to electromagnetic radiation, e.g. emitted by a laser
• CPC Class Codes: A62D 3/19 to plasma
• CPC Class Codes: B01D 19/0084 using an electric current
• CPC Class Codes: B01J 10/002 carried out in foam, aerosol or bubbles
• CPC Class Codes: B01J 19/088 giving rise to electric discharges for heating purposes H05B7/00; for the production of ozone C01B13/11, H01T19/00
• CPC Class Codes: B01J 19/10 employing sonic or ultrasonic vibrations
• CPC Class Codes: B01J 19/12 employing electromagnetic waves
• CPC Class Codes: B01J 2219/0877 Liquid
• CPC Class Codes: B01J 2219/0896 Cold plasma
• CPC Class Codes: B01J 2219/1215 Single reactor
• CPC Class Codes: B01J 2219/1293 Single source
• CPC Class Codes: C23C 16/26 Deposition of carbon only
• CPC Class Codes: C23C 16/27 Diamond only
• CPC Class Codes: C23C 16/50 using electric discharges generation and control of plasma in discharge tubes for surface treatment H01J37/32, H01J37/34
• CPC Class Codes: C23C 16/511 using microwave discharges
• CPC Class Codes: H05H 1/46 using applied electromagnetic fields, e.g. high frequency or microwave energy H05H1/26 takes precedence
• CPC Class Codes: H05H 1/463 : using antennas or applicators

Abstract

A method and apparatus for generating plasma in a liquid. The apparatus includes an ultrasonic wave generator for generating bubbles in the liquid, and an electromagnetic wave generator for continuously irradiating electromagnetic waves to the liquid from within the liquid in order to generate plasma. The method of generating plasma in a liquid includes the steps of generating bubbles in the liquid by irradiating ultrasonic waves in the liquid, and generating plasma in the bubbles by continuously irradiating electromagnetic waves from within the liquid to the bubbles.

Claims

1. A submerged plasma generating apparatus comprising bubble generating means for generating bubbles in a liquid, and an electromagnetic wave generator for continuously irradiating electromagnetic waves to the liquid from within the liquid.

2. The submerged plasma generating apparatus according to claim 1, wherein the bubble generating means comprises a heating device.

3. The submerged plasma generating apparatus according to claim 1, wherein the bubble generating means comprises a decompression device.

4. The submerged plasma generating apparatus according to claim 1, wherein the bubble generating means comprises an ultrasonic wave generator for irradiating ultrasonic waves in a liquid.

5. The submerged plasma generating apparatus according to claim 1, further comprising a substrate mount for mounting of a substrate being an object being formed with a thin film.

6. The submerged plasma generating apparatus according to claim 1, wherein the liquid contains hydrocarbon.

7. The submerged plasma generating apparatus according to claim 6, wherein the liquid contains dodecane.

8. The submerged plasma generating apparatus according to claim 5, wherein an amorphous carbon film is formed on surfaces of the substrate.

9. The submerged plasma generating apparatus according to claim 5, wherein a silicon carbide film is formed on surfaces of the substrate.

10. The submerged plasma generating apparatus according to claim 5, further comprising a vessel for accommodating therein a liquid, supply means for continuously supplying the liquid to the vessel, and discharge means for discharging the liquid from the vessel.

11. The submerged plasma generating apparatus according to claim 4, wherein the liquid contains harmful substances and plasma is generated in the liquid for decomposing harmful substances.

12. The submerged plasma generating apparatus according to claim 11, wherein the liquid contains dioxin or polychlorinated biphenyl (PCB).

16. The submerged plasma generating apparatus according to claim 2, further comprising a substrate mount for mounting of a substrate being an object being formed with a thin film.

17. The submerged plasma generating apparatus according to claim 3, further comprising a substrate mount for mounting of a substrate being an object being formed with a thin film.

18. The submerged plasma generating apparatus according to claim 4, further comprising a substrate mount for mounting of a substrate being an object being formed with a thin film.

19. The submerged plasma generating apparatus according to claim 2, wherein the liquid contains hydrocarbon.

20. The submerged plasma generating apparatus according to claim 3, wherein the liquid contains hydrocarbon.

13. A submerged plasma generating method of generating bubbles in a liquid, and continuously irradiating electromagnetic waves from within the liquid on bubbles for generating plasma in the bubbles.

14. A harmful decomposition method with submerged plasma, the method comprising irradiating ultrasonic waves in a liquid, which contains harmful substances, for generating bubbles in the liquid, and continuously irradiating electromagnetic waves from within the liquid on the bubbles for generating plasma in the bubbles to decompose harmful substances in the liquid.

15. The harmful decomposition method with submerged plasma, according to claim 14, wherein the liquid contains dioxin or polychlorinated biphenyl.

21. A method of forming a silicon carbide film on surfaces of a substrate, the method comprising irradiating ultrasonic waves in a liquid, which contains silicon, to generate bubbles in the liquid, continuously irradiating electromagnetic waves from within the liquid on the bubbles to generate plasma in the bubbles, and causing the bubbles to come into contact with the substrate.