Method for controlling conductivity of Ga2O3single crystal

• US 7,727,865 B2
• Filed: 01/14/2005
• Issued: 06/01/2010
• Est. Priority Date: 02/18/2004
• Status: Active Grant

• Current Assignee: Waseda University (Waseda University Educational Association)
• Original Assignee: Waseda University (Waseda University Educational Association)
• Inventors: Aoki, Kazuo, Shimamura, Kiyoshi, Ichinose, Noboru, Garcia Villora, Encarnacion Antonia
• Primary Examiner(s): Nguyen; Ha Tran T
• Assistant Examiner(s): WHALEN, DANIEL B
• Application Number:
  US10/589,852
• Publication Number:
  US 20070166967A1
• Time in Patent Office: 1,964 Days
• Field of Search: 438/510, 438/514, 438/937, 257/E31.017, 257/E33.002
• US Class Current: 438/510
• CPC Class Codes: C30B 13/00 Single-crystal growth by zone-melting; Refining by zone-melting C30B17/00 takes precedence; by changing the cross-section of the treated solid C30B15/00; under a protective fluid C30B27/00; for the growth of homogeneous polycrystalline material with defined structure C30B28/00
• CPC Class Codes: C30B 29/16 Oxides
• CPC Class Codes: H01L 2224/48463 the connecting portion on the bonding area of the semiconductor or solid-state body being a ball bond
• CPC Class Codes: H01L 2224/49107 on the semiconductor or solid-state body
• CPC Class Codes: H01L 33/26 Materials of the light emitting region
• CPC Class Codes: Y10S 438/937 Hillock prevention

Abstract

To provide a method of controlling a conductivity of a Ga₂O₃ system single crystal with which a conductive property of a β-Ga₂O₃ system single crystal can be efficiently controlled.

The light emitting element includes an n-type β-Ga₂O₃ substrate, and an n-type β-AlGaO₃ cladding layer, an active layer, a p-type β-AlGaO₃ cladding layer and a p-type β-Ga₂O₃ contact layer which are formed in order on the n-type β-Ga₂O₃ substrate. A resistivity is controlled to fall within the range of 2.0×10⁻³ to 8×10² Ωcm and a carrier concentration is controlled to fall within the range of 5.5×10¹⁵ to 2.0×10¹⁹/cm³ by changing a Si concentration within the range of 1×10⁻⁵ to 1 mol %.

Claims

1. A method of controlling a conductivity of a Ga₂O₃ system single crystal, comprising:

adding an n-type dopant to the Ga₂O₃ system single crystal to change a resistivity of the Ga₂O₃ system single crystal substantially linearly with an added amount of the n-type dopant,

wherein the n-type dopant comprises one of Zr, Si, Hf, Ge, Sn, and Ti,

wherein the Ga₂O₃ system single crystal is prepared with a Ga₂O₃ polycrystalline raw material, and

wherein the Ga₂O₃ polycrystalline raw material has a purity of 6N.

2. The method of controlling a conductivity of a Ga₂O₃ system single crystal according to claim 1, wherein a value of 2.0×

10<sup>−

3</sup> to 8.0×

10² Ω

cm is obtained as the resistivity by said adding said n-type dopant.

3. The method of controlling a conductivity of a Ga₂O₃ system single crystal according to claim 2, wherein a carrier concentration of the Ga₂O₃ system single crystal is controlled to fall within a range of 5.5×

10¹⁵ to 2.0×

10¹⁹ cm³ as a range of the resistivity.

4. The method of controlling a conductivity of a Ga₂O₃ system single crystal according to claim 1, wherein the n-type dopant comprises one of Si, Hf, and Sn.

5. The method of controlling a conductivity of a Ga₂O₃ system single crystal according to claim 1, wherein the n-type dopant comprises one of Si and Hf.

6. A method of controlling a conductivity of a Ga₂O₃ system single crystal, comprising:

contacting a Ga₂O₃ polycrystalline raw material comprising a predetermined dopant to a Ga₂O₃ seed crystal; and

growing the Ga₂O₃ system single crystal on the Ga₂O₃ seed crystal such that said predetermined dopant is substituted for Ga in the Ga₂O₃ system single crystal to obtain a desired resistivity in the Ga₂O₃ system single crystal of 1×

10³ Ω

cm or greater,

wherein said predetermined dopant comprises a p-type dopant for controlling said conductivity of the Ga₂O₃ system single crystal, said p-type dopant comprising one of H, Li, Na, K, Rb, Cs, Fr, Be, Mg, Ca, Sr, Ba, Ra, Mn, Fe, Co, Ni, Pd, Cu, Ag, Au, Zn, Cd, Hg, Tl, and Pb, and wherein said Ga₂O₃ polycrystalline raw material has a purity of 6N.

7. The method of controlling a conductivity of a Ga₂O₃ system single crystal according to claim 6, wherein said conductivity of the Ga₂O₃ system single crystal is dependent on an added amount of said p-type dopant.

8. A method of manufacturing a Ga₂O₃ system single crystal, comprising:

adding an n-type dopant to the Ga₂O₃ system single crystal, said n-type dopant comprising one of Zr, Si, Hf, Ge, Sn, and Ti; and

manufacturing the Ga₂O₃ system single crystal having a resistivity depending on an added amount of said n-type dopant by changing the resistivity of the Ga₂O₃ system single crystal substantially linearly with the added amount of said n-type dopant,

wherein the Ga₂O₃ system single crystal is prepared with a Ga₂O₃ polycrystalline raw material, and

wherein the Ga₂O₃ polycrystalline raw material has a purity of 6N.

9. The method of manufacturing a Ga₂O₃ system single crystal according to claim 8, wherein said n-type dopant comprises one of Si, Hf, and Sn.