Device for improving plasma activity PVD-reactors

• US 20070017804A1
• Filed: 07/21/2006
• Published: 01/25/2007
• Est. Priority Date: 07/22/2005
• Status: Abandoned Application

• Current Assignee: Sandvik Intellectual Property AB (Sandvik AB)
• Original Assignee: Sandvik Intellectual Property AB (Sandvik AB)
• Inventors: Myrtveit, Toril, Rodmar, Markus, Selinder, Torbjorn
• Application Number:
  US11/490,502
• Publication Number:
  US 20070017804A1
• Time in Patent Office: Days
• US Class Current: 204/298.160
• CPC Class Codes: C23C 14/022 by means of bombardment with energetic particles or radiation
• CPC Class Codes: C23C 14/355 using electrons, e.g. triode sputtering
• CPC Class Codes: H01J 37/3233 using charged particles
• CPC Class Codes: H01J 37/3405 Magnetron sputtering

Abstract

The present invention relates to a device for improving plasma activity in a magnetron sputtering reactor containing substrates to be coated where a primary plasma is created by a DC or AC voltage applied between the substrates and an additional electrode. Increased plasma activity is obtained by thermionic emission of electrons from a hot filament heated by either DC or AC current or combinations thereof. The device is particularly useful for increasing the adhesion of layers deposited by magnetron sputtering on cutting tool inserts made of cemented carbide, high speed steels, cermets, ceramics or cubic boron nitride.

Claims

1. Device for improving plasma activity in a coating reactor containing substrates to be coated, where a primary plasma is created by a DC or AC voltage applied between the substrates and at least one additional electrode, said device comprising a thermionic emitter, heated by either DC or AC current or combinations thereof.

2. A device of claim 1 wherein the hot filament is the cathode of a system and the corresponding anode is one or more separate dedicated electrodes.

3. A device of claim 1 wherein the hot filament is the cathode of a system and the corresponding anode is the reactor wall.

4. A device of claim 2 or 3 wherein the corresponding anode is the at least one additional electrode used to create the primary plasma.

5. A device of claim 1 wherein the hot filament extends from top to bottom in the reactor.

6. A device of claim 5 wherein the filament is either W, thoriated W or any coated filament and the coating is an efficient electron emitter.

7. A device of claim 5 wherein the hot filament is protected by a chamber or a cage with small apertures from which the emitted electrons can escape with a potential in the range from the potential of the hot filament to the potential of the corresponding anode.

8. A device of claim 1 wherein the coating reactor is a PVD reactor.

9. A device of claim 1 wherein the thermionic emitter comprises at least one filament.

10. A device of claim 9 wherein the thermionic emitter comprises more than one filament.

11. A device of claim 10 wherein the filaments are connected in series.

12. A device of claim 10 wherein the filaments are connected in parallel.

13. A device of claim 8 wherein the PVD coating system is a magnetron sputtering system.

14. Use of the device of claim 1 in a PVD reactor to achieve enhanced sputter etching prior to the deposition of layers on cutting tool inserts made of cemented carbide, high speed steels, cermets, ceramics, cubic boron nitride or metals steel, as well as coating of metal wires, rods and bands.

15. The use of the device of claim 14 to achieve enhanced sputter etching prior to the deposition of layers on cutting tool inserts made of cemented carbide, high speed steels, cermets, ceramics or cubic boron nitride.