Surface treatment method and surface treatment device

• US 20050269577A1
• Filed: 06/07/2005
• Published: 12/08/2005
• Est. Priority Date: 06/08/2004
• Status: Abandoned Application

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Ueda, Tetsuzo, Ueda, Daisuke
• Application Number:
  US11/146,036
• Publication Number:
  US 20050269577A1
• Time in Patent Office: Days
• US Class Current: 257/80
• CPC Class Codes: C25F 3/02 Etching
• CPC Class Codes: C25F 3/12 of semiconducting materials
• CPC Class Codes: H01L 21/30625 With simultaneous mechanical treatment, e.g. mechanico-chemical polishing
• CPC Class Codes: H01L 21/30635 of AIIIBV compounds
• CPC Class Codes: H01L 33/0095 Post-treatment of devices, e.g. annealing, recrystallisation or short-circuit elimination
• CPC Class Codes: H01S 5/0213 Sapphire, quartz or diamond based substrates
• CPC Class Codes: H01S 5/0217 Removal of the substrate
• CPC Class Codes: H01S 5/04252 characterised by the material
• CPC Class Codes: H01S 5/04254 characterised by the shape
• CPC Class Codes: H01S 5/18369 based on dielectric materials
• CPC Class Codes: H01S 5/32341 blue laser based on GaN or GaP

Abstract

The present invention is conceived in order to accomplish an object of providing a surface treatment method and a surface treatment device that can planarize, at high speed, the surface of a nitride semiconductor with an excellent evenness. The surface treatment device includes an electrolyte supply port 15 for supplying a KOH electrolyte 14 containing fine metal particles and an abrasive, a storage container 40 having an opening on the top surface and is for storing the KOH electrolyte 14 supplied from the electrolyte supply port 15, a wafer holder 12 for fixing the GaN substrate 11 and bringing the surface of the GaN substrate 11 into contact with the KOH electrolyte 14 by impregnating the surface of the substrate into the KOH electrolyte 14 in the storage container 40 from above, a load 13 placed on the wafer holder 12, a device housing 16, a polishing pad 17 for polishing the surface of the GaN substrate 11 and an ultraviolet light source 42.

Claims

1. A surface treatment method for planarizing a surface of a substrate, comprising

planarizing of the surface of the substrate by performing etching of the surface using an electrolyte containing fine metal particles in a way that the surface is brought into contact with the electrolyte.

2. The surface treatment method according to claim 1,

wherein the etching is performed together with irradiation of light on the surface of the substrate that is brought into contact with the electrolyte.

3. The surface treatment method according to claim 2,

wherein energy of the light to be irradiated on the surface of the substrate is greater than a band gap of the substrate.

4. The surface treatment method according to claim 2,

wherein the light to be irradiated on the surface of the substrate is a laser light.

5. The surface treatment method according to claim 1,

wherein the surface of the substrate is brought into contact with the electrolyte by impregnating the surface of the substrate into the electrolyte or by bringing the surface of the substrate into contact with a surface of a holding member into which the electrolyte is infiltrated.

6. The surface treatment method according to claim 1,

wherein the fine metal particles are made of one of Pt, Au and Ag.

7. The surface treatment method according to claim 1,

wherein the electrolyte includes an abrasive, and

the etching is performed together with polishing of the surface of the substrate.

8. The surface treatment method according to claim 1,

wherein an electrically conductive member is placed in the electrolyte, and

the etching of the surface of the substrate is performed together with application of voltage to between the surface and the electrically conductive member.

9. The surface treatment method according to claim 1,

wherein the etching of the surface of the substrate is performed together with heating of the substrate.

10. The surface treatment method according to claim 1,

wherein the substrate is made of a compound semiconductor including nitrogen.

11. A surface treatment device for planarizing a surface of a substrate, comprising:

a storage unit operable to store an electrolyte containing fine metal particles; and

a contact unit operable to bring the surface of the substrate into contact with the electrolyte.

12. The surface treatment device according to claim 11, further comprising

a light source for irradiating light on the surface of the substrate.

13. The surface treatment device according to claim 12,

wherein the light source is a laser light source.

14. The surface treatment device according to claim 11,

wherein said storage unit is a storage container having an opening on the top surface and is for storing the electrolyte, and

said contact unit is operable to fix the substrate and operable to impregnate the surface of the substrate into the electrolyte in the storage container.

15. The surface treatment device according to claim 11,

wherein said storage unit is a holding member into which the electrolyte is infiltrated, and

said contact unit is operable to fix the substrate and operable to bring the surface of the substrate into contact with the holding member.

16. The surface treatment device according to claim 11, further comprising

a polishing pad for polishing the surface of the substrate, the pad being placed facing the surface.

17. The surface treatment device according to claim 11, further comprising

a polishing pad for polishing the surface of the substrate, the pad being placed facing the surface of the substrate, and

a light source for irradiating light on the surface of the substrate, the light source being placed opposite the substrate across the polishing pad,

wherein the polishing pad has an opening.

18. The surface treatment device according to claim 11,

wherein said storage unit is a storage container having an opening on the top surface and is for storing the electrolyte,

said contact unit is operable to fix the substrate and operable to impregnate the surface of the substrate into the electrolyte in the storage container,

the surface treatment device further comprises:

a polishing pad for polishing the surface of the substrate, the polishing pad being placed facing the surface; and

a light source for irradiating the light on the surface of the substrate, the light source being placed at a side of the storage container; and

a side surface of the storage container is transparent to the light emitted by the light source.

19. The surface treatment device according to claim 11, further comprising:

an electrically conductive polishing pad for polishing the surface of the substrate, the polishing pad being placed facing the surface;

electrodes placed in contact with the substrate; and

an electronic power supply for applying voltage to between the electrodes and the polishing pad.

20. The surface treatment device according to claim 11, further comprising a heater for heating the substrate.