ZINC OXIDE BASED SUBSTRATE AND METHOD FOR MANUFACTURING ZINC OXIDE BASED SUBSTRATE

• US 20110204355A1
• Filed: 08/26/2010
• Published: 08/25/2011
• Est. Priority Date: 08/28/2009
• Status: Abandoned Application

• Current Assignee: Tokyo Denpa Co., Ltd. (Murata Manufacturing Co Limited), ROHM Co., Ltd.
• Original Assignee: Mitsubishi Chemical Corporation (Mitsubishi Chemical Group Corp.), Tokyo Denpa Co., Ltd. (Murata Manufacturing Co Limited), ROHM Co., Ltd.
• Inventors: YUJI, Hiroyuki, NAKAHARA, Ken, SUZUKI, Takao
• Application Number:
  US12/869,227
• Publication Number:
  US 20110204355A1
• Time in Patent Office: Days
• US Class Current: 257/43
• CPC Class Codes: C04B 2235/3206 Magnesium oxides or oxide-forming salts thereof
• CPC Class Codes: C04B 2235/3284 Zinc oxides, zincates, cadmium oxides, cadmiates, mercury oxides, mercurates or oxide forming salts thereof
• CPC Class Codes: C04B 2235/72 Products characterised by the absence or the low content of specific components, e.g. alkali metal free alumina ceramics
• CPC Class Codes: C04B 2235/721 Carbon content
• CPC Class Codes: C04B 35/453 based on zinc, tin, or bismuth oxides or solid solutions thereof with other oxides, e.g. zincates, stannates or bismuthates
• CPC Class Codes: C23C 14/086 of zinc, germanium, cadmium, indium, tin, thallium or bismuth
• CPC Class Codes: C23C 14/24 Vacuum evaporation
• CPC Class Codes: H01L 21/02403 Oxides
• CPC Class Codes: H01L 21/02414 Oxide semiconducting materials not being Group 12/16 materials, e.g. ternary compounds
• CPC Class Codes: H01L 21/02554 Oxides
• CPC Class Codes: H01L 21/02565 Oxide semiconducting materials not being Group 12/16 materials, e.g. ternary compounds
• CPC Class Codes: H01L 21/02631 Physical deposition at reduced pressure, e.g. MBE, sputtering, evaporation

Abstract

A zinc oxide based substrate satisfies a condition that impurities Si, C, Ge, Sn, and Pb which are Group IV elements each have a concentration of 1×10¹⁷ cm⁻³ or less. More preferably, the zinc oxide based substrate 2 satisfies a condition that impurities Li, Na, K, Rb, and Fr which are Group I elements each have a concentration of 1×10¹⁶ cm⁻³ or less. The impurity concentration of a zinc oxide based semiconductor grown on the zinc oxide based substrate can be reduced in this manner.

Claims

1. A zinc oxide based substrate comprising:

an impurity of a Group IV element of any of Si, C, Ge, Sn, and Pb, the impurity having a concentration of 1×

10¹⁷ cm<sup>−

3</sup> or less.

4. The zinc oxide based substrate of claim 1, wherein:

the zinc oxide based substrate is formed of Mg_xZn_1-xO (0≦

X≦

0.5).

2. A zinc oxide based substrate comprising:

an impurity of a Group I element of any of Li, Na, K, Rb, and Fr, the impurity having a concentration of 1×

10¹⁶ cm<sup>−

3</sup> or less; and

an impurity of a Group IV element of any of Si, C, Ge, Sn, and Pb, the impurity having a concentration of 1×

10¹⁷ cm<sup>−

3</sup> or less.

3. The zinc oxide based substrate of claim 2, wherein:

the Group I element is Li; and

the Group IV element is Si.

7. The zinc oxide based substrate of claim 2, wherein:

the zinc oxide based substrate is formed of Mg_xZn_1-xO (0≦

X≦

0.5).

8. The zinc oxide based substrate of claim 3, wherein:

the zinc oxide based substrate is formed of Mg_xZn_1-xO (0≦

X≦

0.5).

5. Method for manufacturing a zinc oxide based substrate comprising:

the step of forming an ingot made of a zinc oxide based semiconductor by a hydrothermal synthesis method in which a zinc oxide based material with a weight ratio of Si being 100 ppm or less is used.

6. The method for manufacturing a zinc oxide based substrate of claim 5, wherein:

the method includes the step of heat-processing the zinc oxide based substrate at 1300°

C. or more.