| US 7,535,162 B2 | ||
| Zinc oxide phosphor, process for producing the same and light emitting device | ||
| Naoki Ohashi, Ibaraki (Japan); Takamasa Ishigaki, Ibaraki (Japan); Hiroyuki Taguchi, Ibaraki (Japan); Isao Sakaguchi, Ibaraki (Japan); Hajime Haneda, Ibaraki (Japan); and Takashi Sekiguchi, Ibaraki (Japan) | ||
| Assigned to National Institute for Materials Science, Tsukuba-shi (Japan) | ||
| Appl. No. 10/554,724 PCT Filed Apr. 30, 2004, PCT No. PCT/JP2004/006402 § 371(c)(1), (2), (4) Date Jan. 23, 2007, PCT Pub. No. WO2004/096949, PCT Pub. Date Nov. 11, 2004. |
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| Claims priority of application No. 2003-124743 (JP), filed on Apr. 30, 2003. | ||
| Prior Publication US 2007/0158615 A1, Jul. 12, 2007 | ||
| Int. Cl. H01J 1/62 (2006.01) | ||
| U.S. Cl. 313—503 [313/486; 252/301.6 R] | 11 Claims |
| 1. A zinc oxide phosphor comprising:
zinc oxide;
at least one of aluminum, gallium, and indium doped to said zinc oxide; and
at least one of lithium and sodium doped to said zinc oxide,
wherein a surface layer containing solid-soluted hydrogen is formed at a hydrogen concentration controlled so as to inactivate
defects formed in the phosphor to contribute to non-radiative transition and not to inactivate defects contributing to radiative
transition, or hydrogen is contained at a concentration controlled so as to inactivate defects formed in the phosphor to contribute
to non-radiative transition over the entire region of a grain of the phosphor and not to inactivate defects contributing to
radiative transition, and
wherein when the phosphor is excited with ultraviolet rays or electromagnetic waves or electron rays at a shorter wavelength
than that of ultraviolet rays, the maximum intensity of an emission spectrum at room temperature is observed in a wavelength
range of 550 to 650 nm, and the spectrum is a continuous spectrum extending from 400 nm or less at the short-wavelength tail
and to 800 nm or more at the long-wavelength tail.
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