Nerima-ku, Japan
Nerima-ku, Japan

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Patent
Koha Co., Tamura Corporation and Japan National Institute of Materials Science | Date: 2016-06-15

Provided is a light emitting device which is suitable for a lighting apparatus, such as a projector, requiring high brightness and high light intensity exhibits little change in light emission colour and a low reduction in light emission intensity during usage, and uses a remote phosphor. According to one embodiment of the present invention, the light emitting device (10) has: an LED element (12); a side wall (13) which surrounds the LED element (12); a phosphor layer (15) which is fixed to the side wall (13) with an adhesive layer (14) therebetween, and is positioned above the LED element (12); and a metal pad (11) as a heat dissipating member. The side wall (13) has: an insulating base (13b) which surrounds the LED element (12); and a metal layer (13a) which is formed on a side surface at the LED element (12) side of the base (13b), and is in contact with the metal pad (11) and the adhesive layer (14). The adhesive layer (14) is: a resin layer that comprises a resin containing particles which have higher thermal conductivity than the resin; or a layer that comprises solder.


Patent
Koha Co. and Japan National Institute of Materials Science | Date: 2016-03-30

Provided are: a YAG-based single crystal phosphor which produces fluorescence of a non-conventional color; and a phosphor-containing member and a light emitting device, each of which is provided with this single crystal phosphor. Provided as one embodiment of the present invention is a single crystal phosphor which has a composition represented by composition formula (Y_(1-a-b)Lu_(a)Ce_(b))_(3+c)Al_(5-c)O_(12) (wherein 0 a 0.9994, 0.0002 b 0.0067 and -0.016 c 0.315), and which has an emission spectrum having CIE chromaticity coordinates x and y satisfying the relation -0.4377x + 0.7384 y -0.4585x + 0.7504 when the peak wavelength of the excitation light is 450 nm at the temperature of 25C.


Patent
Koha Co. and Japan National Institute of Materials Science | Date: 2015-03-04

One purpose of the invention is to provide a phosphor with excellent quantum efficiency, a method for manufacturing the same, and a light-emitting device that uses this phosphor. One embodiment provides a phosphor comprising monocrystals with YAG crystals as a matrix, the quantum efficiency of the phosphor at 25C being 92% or higher at an excitation light wavelength of 460 nm.


Provided are: a method for cultivating a -Ga_(2)O_(3) single crystal which makes it possible to obtain a flat -Ga_(2)O_(3) single crystal having high crystal quality; a -Ga_(2)O_(3)-single-crystal substrate; and a method for producing the same. Provided is one embodiment which is a method for cultivating a -Ga_(2)O_(3) single crystal (25) including a step for contacting a flat seed crystal (20) with a Ga_(2)O_(3) melt (12), and a step for pulling up the seed crystal (20) and growing a flat -Ga_(2)O_(3) single crystal (25) having a principal surface (26a) which intersects a surface (100), in a manner such that the crystal information of the vaporized material (23) of the Ga_(2)O_(3) melt (12) adhered to the principal surface of the seed crystal (20) is not passed on, wherein when growing the -Ga203 single crystal (25), the shoulder of the -Ga_(2)O_(3) single crystal (25); is only widened in the thickness direction (t).


Patent
Koha Co. and Japan National Institute of Materials Science | Date: 2016-08-31

As one of purposes, the present invention provides: a single-crystal phosphor which can exhibit excellent properties under high-temperature conditions; and a light-emitting device in which the phosphor is used. As one embodiment, a single-crystal phosphor is provided, which has a chemical composition represented by the compositional formula: (Y_(1-x-y-z)Lu_(x)Gd_(y)Ce_(z))_(3+a)Al_(5-a)O_(12) (0 x 0.9994, 0 y 0.0669, 0.0002 z 0.0067, -0.016 a 0.315).


Patent
Tamura Corporation and Koha Co. | Date: 2015-02-27

A Ga_(2)O_(3)-based single crystal substrate includes a main surface including BOW of not less than 13 m and not more than 0 m. The main surface may further include WARP of not more than 25 m. The main surface may further include TTV of not more than 10 m.


Patent
Tamura Corporation and Koha Co. | Date: 2015-02-27

A -Ga_(2)O_(3)-based single crystal substrate includes an average dislocation density of less than 7.3110^(4 )cm^(2). The average dislocation density may be not more than 6.1410^(4 )cm^(2). The substrate may further include a main surface including a plane orientation of (201), (101) or (001). The substrate may be free from any twinned crystal.


Patent
Tamura Corporation and Koha Co. | Date: 2016-03-02

Provided is a method for growing a -Ga_(2)O_(3)-based single crystal, whereby it becomes possible to grow a -Ga_(2)O_(3)-based single crystal having a small variation in crystal structure and also having high quality in the direction of the b axis. In one embodiment, a method for growing a -Ga_(2)O_(3)-based single crystal is provided, which comprises a step of growing a flat-plate-shaped Sn-containing -Ga_(2)O_(3)-based single crystal in the direction of the b axis using a seed crystal.


Provided are: a method for cultivating a -Ga_(2)O_(3) single crystal which makes it possible to obtain a wide -Ga_(2)O_(3) seed crystal and is to be used in the cultivation of a flat -Ga_(2)O_(3) single crystal which minimizes widening of the shoulder in the width direction; a -Ga_(2)O_(3)-single-crystal substrate obtained by using the same; and a production method therefor. Provided is one embodiment which is a method for cultivating a -Ga_(2)O_(3) single crystal which uses the EFG method and includes: a step for raising a Ga_(2)O_(3) melt (12) inside a crucible (13) up to a die (14) opening (14b) via a die (14) slit (14a), and while the horizontal position of a seed crystal (20) is shifted in the width direction (W) from the width direction (W) center of the die (14), contacting the seed crystal (20) and the Ga_(2)O_(3) melt (12) in the opening (14b) of the die (14); and a step for pulling up the seed crystal (20) which contacted the Ga_(2)O_(3) melt (12), and growing the -Ga_(2)O_(3) single crystal (25).


Patent
Tamura Corporation and Koha Co. | Date: 2015-09-30

A -Ga_(2)O_(3)-based single crystal substrate includes a -Ga_(2)O_(3)-based single crystal. The -Ga_(2)O_(3)-based single crystal includes a full width at half maximum of an x-ray rocking curve of less than 75 seconds.

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