Device for Treating an Object with Plasma

• US 20150243485A1
• Filed: 07/22/2013
• Published: 08/27/2015
• Est. Priority Date: 07/20/2012
• Status: Abandoned Application

• Current Assignee: Plasma-Therm Corporation
• Original Assignee: Nanoplas Inc.
• Inventors: Segers, Marc, Baujon, Gilles, Guidotti, Emmanuel, Pilloux, Yannick, Rabinzohn, Patrick, Richard, Julien, Girault, Vincent
• Application Number:
  US14/415,976
• Publication Number:
  US 20150243485A1
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H01J 2237/334 Etching
• CPC Class Codes: H01J 37/32082 Radio frequency generated discharge H01J37/32357, H01J37/32366, H01J37/32394 and H01J37/32403 take precedence
• CPC Class Codes: H01J 37/32357 Generation remote from the workpiece, e.g. down-stream
• CPC Class Codes: H01J 37/32366 Localised processing
• CPC Class Codes: H01J 37/32403 Treating multiple sides of workpieces, e.g. 3D workpieces
• CPC Class Codes: H01J 37/32449 Gas control, e.g. control of the gas flow
• CPC Class Codes: Y10T 428/24802 Discontinuous or differential coating, impregnation or bond [e.g., artwork, printing, retouched photograph, etc.]

Abstract

A system for treating an object with plasma includes a vacuum processing chamber having a holder on which the object to be treated is placed, at least two subassemblies each including at least one plasma source able to generate a plasma and being supplied with radio-frequency power Pi and with a gas i of independent flow rate ni. The plasma generated by one of the subassemblies is a partially ionized gas or gas mixture of different chemical nature from the plasma generated by the other subassembly or subassemblies. A process for selectively treating a composite object employing such a device is described.

Claims

1-17. -17. (canceled)

18. A system for the treatment of an object by plasma comprising:

a treatment vacuum chamber having a support on which the object to be treated is placed; and

at least two subassemblies each comprising at least one plasma source allowing a plasma to be generated, each plasma source of a subassembly being supplied by radio frequency power Pi and independently by a gas i at a flow-rate ni, wherein plasma generated by one subassembly is a partially ionized gas or a gas mixture, of a different chemical nature from plasma generated by the other subassembly or subassemblies.

19. The system according to claim 18 wherein each source of plasma of a subassembly comprises:

a gas inlet system;

a discharge chamber made of a plasma-inert material;

a device for coupling the radiofrequency (RF) power to the discharge chamber; and

a gas outlet.

20. The system according to claim 18 further comprising a control device to control each of the subassemblies depending upon a specific parameterization by application of radiofrequency power Pi and/or a flow-rate of gas ni specific to each subassembly.

21. The system according to claim 18 wherein each subassembly comprises a gas inlet specific to the subassembly connected to the gas inlet of each plasma source of the subassembly.

22. The system according to claim 18 wherein each subassembly comprises a conducting element connected to the coupling device of each plasma source of the subassembly.

23. The system according to claim 18 wherein the subassemblies are arranged along concentric rings.

24. The system according to claim 18 wherein the subassemblies are arranged in parallel.

25. The system according to claim 24 wherein each subassembly comprises at least two plasma sources, each plasma source comprising two chambers in series.

26. A selective plasma treatment process of a composite object comprising at least two different materials A and B, the process implementing a treatment system according to claim 18 and comprising the following steps:

generating a first plasma by a first of the subassemblies and treating the object using the first plasma;

generating a second plasma by a second of the subassemblies and treating the object using the second plasma.

27. The process according to claim 26 wherein the plasma generation steps are repeated alternately, or with partial or total overlap.

28. The process according to claim 26 wherein the plasma generating steps are repeated with a partial overlap of the steps by at most 25%.

29. A process for an etching treatment of a composite object that has at least two layers of different materials A and B with the layer of material A covering at least partially the layer of material B, the process comprising:

treating, using a first plasma, at least a first zone of the object comprising on the surface, the material A, said treating using the first plasma comprising a passivation or activation of material B; and

treating, using a second plasma, at least a second zone of the object comprising on the surface, the material A, the treating using the second plasma comprising partial or total removal of material A, to form a zone comprising the material B on the surface when the removal is total, the process able to start either with a step of activation or passivation using the first plasma, or with a step of removal using the second plasma.

30. The process according to claim 29 wherein the first and second treating steps are performed in an alternating manner according to a periodicity varying between 0.5 seconds and 120 seconds until a desired removal of material A is obtained.

31. The process according to claim 29 wherein a ratio of a duration of the activation step or the passivation step to a duration of the removal varies between 0.1 and 10.

32. The process according to claim 29 wherein the first material A is silicon nitride Si₃N₄ and the second material B is the oxide of silicon SiO₂.

33. An etched composite object obtained by the process according to claim 29.

34. The composite object according to claim 33 comprising one of an integrated circuit wafer, a substrate for a flat screen, a substrate for solar cells, or a substrate for an electronically printed device.