Kabushiki Kaisha Toshiba

Toshiba Materials Co., Ltd.

Toshiba Lighting & Technology Corporation

Meijo University

Yokohama National University

Samsung Electronics Co., Ltd.

Ryosuke Hiramatsu

Masaaki Tamatani

Yumi Fukuda

Keiko Albessard

Masahiro Kato

Naotoshi Matsuda

Kunio Ishida

Yasushi Hattori

Naomi Shida

Iwao Mitsuishi

Hironori Asai

Aoi Okada

Kazuaki Ootsuka

Yoshihito Tsutsui

Katsutoshi Komeya

Shinya Nunoue

Junichi Tatami

Toru Wakihara

Takahiro Sato

Hideaki Hirabayashi

Satoshi Kamiyama

Atsuya Sasaki

Hisayo Uetake

Shinji Saito

Shigeya Kimura

Jun Tamura

Hitoshi Yoneda

Kazuaki Otsuka

Jun-ichi Tatami

Tohru Wakihara

A semiconductor light-emitting element having an emission peak wavelength of 395 nm or more and 425 nm or less, comprises: a substrate including a first surface and a second surface, at least one surface selected from the group consisting of the first and second surfaces having an uneven region; a semiconductor layer on the first surface; and a multilayer reflective film on the second surface or the semiconductor layer, wherein the multilayer reflective film includes a structure having a plurality of first dielectric films and a plurality of second dielectric films, the first dielectric films and the second dielectric films being alternately stacked.

Semiconductor light-emitting element

A semiconductor light-emitting element according to an embodiment has a light emission peak wavelength not less than 380 nm and not more than 425 nm. The semiconductor light-emitting element includes a stacked structure including a reflective layer, a substrate provided on the reflective layer, and a semiconductor layer provided on the substrate. An uneven structure is provided in a surface of the substrate on the semiconductor layer side. The semiconductor layer includes a buffer layer made of aluminum nitride and having a thickness not less than 10 nm and not more than 100 nm. The buffer layer includes oxygen; and 0.01&#x2264;O/O&#x2264;0.5 is satisfied, where O(at %) is the oxygen concentration at a depth of 3 nm of the buffer layer, and O(at %) is the oxygen concentration at a depth of 8 nm of the buffer layer.

Semiconductor light-emitting element and method for manufacturing same

Embodiments of the present invention provide a phosphor improved in the emission intensity maintenance ratio without impairing the emission intensity and further a light-emitting device employing that phosphor. The phosphor is activated by manganese and has a basic structure comprising at least one element selected from the group consisting of potassium, sodium and calcium; at least one element selected from the group consisting of silicon and titanium; and fluorine. In an IR absorption spectrum of the phosphor, the intensity ratio of the peak in 3570 to 3610 cmto that in 1200 to 1240 cmis 0.1 or less.

Phosphor, producing method thereof, and light-emitting device employing the phosphor

A red-light emitting phosphor is provided, having a basic composition represented by K(Si,Mn)Fand also having a particular Raman spectrum, wherein the intensity ratio I/I, which is a ratio of (I) the peak in a Raman shift of 600&#xb1;10 cmassigned to Mn&#x2014;F bonds in the crystal to that (I) in a Raman shift of 650&#xb1;10 cmassigned to Si&#x2014;F bonds in the crystal, is 0.09 to 0.22. This phosphor is produced by bringing a silicon source in contact with an aqueous reaction solution containing potassium permanganate and hydrogen fluoride, wherein a molar ratio of hydrogen fluoride to potassium permanganate is 87 to 127.

Phosphor, manufacturing method thereof, and light-emitting device using the phosphor

A phosphor comprising: Wherein the phosphor satisfies I (2,500-3,000)/I (1,200-1,240)&#x3c;0.04, when I (1,200-1,240) is an intensity of a highest peak in a range of 1,200-1,240 cmand I (2,500-3,000) is an intensity of a highest peak in a range of 2,500-3,000 cmin an infrared spectrum.

Phosphor and light-emitting device

The present invention provides a red-light emitting phosphor that exhibits high luminous efficacy and emits light when excited by light having an emission peak in the blue region; and a method for manufacturing said phosphor. The phosphor represented by general formula (A):(Si,Ti,Mn)Fand also characterized in that the half-band width of a diffraction pattern attributed to the (400) plane is not less than 0.2&#xb0; determined by X-ray powder diffractometry. This phosphor can be manufactured by preparing a reaction solution consisting of an aqueous solution containing potassium permanganate and hydrogen fluoride, immersing a silicon source in said reaction solution, and reacting them for 20 to 80 minutes.

Phosphor, manufacturing method therefor, and light-emitting device using the phosphor

The present invention provides a red-light emitting phosphor having high luminous efficacy and also a manufacturing method thereof. The phosphor is a red-light emitting phosphor mainly comprising potassium fluorosilicate and having a basic surface composition represented by the formula (A): KSiF. The disclosed phosphor is characterized by being activated by manganese and also characterized in that the amount of manganese on the surface is not more than 0.2 mol % based on the total amount of all the elements on the surface. This phosphor can be manufactured by washing with a weak acid a product obtained by placing a silicon source to react in contact with a reaction solution containing potassium permanganate.

A light-emitting device of an embodiment includes a light-emitting element emitting blue excitation light and a first phosphor excited by the blue excitation light and emitting fluorescence. A peak wavelength of the fluorescence is not shorter than 520 nm and shorter than 660 nm and the peak wavelength of the fluorescence shifting in the same direction when a peak wavelength of the blue excitation light shifts. The first phosphor is one of a yellow phosphor emitting yellow fluorescence, a green phosphor emitting green fluorescence, a yellow-green/yellow phosphor emitting yellow-green/yellow fluorescence and a red phosphor emitting red fluorescence.

Light-emitting device with phosphor excited by blue excitation light

According to one embodiment, the luminescent material shows a luminescence peak in a wavelength range of 570 to 670 nm when excited with light having an emission peak in a wavelength range of 250 to 520 nm. The luminescent material includes a host material having a crystal structure substantially same as the crystal structure of SrSiAlON. The host material is activated by Eu, and includes Sr and Ca to satisfy a relationship of 0.008&#x2266;M/(M+M)&#x2266;0.114, where Mis a number of moles of Ca and Mis a number of moles of Sr.

Luminescent material

The present invention provides a fluorescent substance excellent both in quantum efficiency and in temperature characteristics, and also provides a process for producing the fluorescent substance. This fluorescent substance is an oxynitride phosphor having a low paramagnetic defect density and comprising aluminum, silicon, either or both of oxygen and nitrogen, and a metal element M, provided that the metal element M is partly replaced with an emission center element R. That phosphor can be produced by the steps of: subjecting a mixture of starting materials to heat treatment under a nitrogen atmosphere so as to obtain an intermediate fired product, and then further subjecting the intermediate fired product to heat treatment under an atmosphere of nitrogen-hydrogen mixed gas.

Process for producing fluorescent substance and fluorescent substance produced thereby

A white light emitting device includes a light emitting element having a peak wavelength at from 430 nm to 460 nm; and a fluorescent layer on the light emitting element containing a red fluorescent material and a green-yellow fluorescent material. The white light emitting device achieves high color rendering properties, a high average color rendering index Ra and a high luminescent efficiency, or a high white efficiency.

White light emitting device with red and green-yellow phosphor

A white light emitting device according to an embodiment includes: a light emitting element having a peak wavelength in a wavelength range of 430 nm or more and 470 nm or less; a first fluorescent material emits light with a first peak wavelength of 525 nm or more and 560 nm or less; a second fluorescent material emits light with a second peak wavelength longer than the first peak wavelength; and a third fluorescent material emits light with a third peak wavelength of 620 nm or more and 750 nm or less, which is longer than the second peak wavelength. The first fluorescent material and the second fluorescent material has a composition of MSiON, and when the first peak wavelength is denoted by &#x3bb;1 (nm), whereas the second peak wavelength is denoted by &#x3bb;2 (nm), 1100&#x2266;&#x3bb;1+&#x3bb;2 and &#x3bb;2&#x2212;&#x3bb;1&#x2266;60 are satisfied.

White light emitting device containing three fluorescent materials having different peak wavelengths

According to one embodiment, the luminescent material emits light having an luminescence peak within a wavelength range of 550 to 590 nm when excited with light having an emission peak in a wavelength range of 250 to 520 nm. The luminescent material has a composition represented by the following formula 1.(SrEu)SiAlON&#x2003;&#x2003;formula 1

A light emitting device according to one embodiment includes a board; plural first light emitting elements mounted on the board to emit light having a wavelength of 250 nm to 500 nm; plural second light emitting elements mounted on the board to emit light having a wavelength of 250 nm to 500 nm; a first fluorescent layer formed on each of the first light emitting elements, the first fluorescent layer including a first phosphor; and a second fluorescent layer formed on each of the second light emitting elements, the second fluorescent layer including a second phosphor. The second phosphor is higher than the first phosphor in luminous efficiency at 50&#xb0; C., and is lower than the first phosphor in the luminous efficiency at 150&#xb0; C.

Light emitting device

The embodiment provides a process for production of an oxynitride fluorescent substance. An compound containing In or Ga is adopted in the process as a material thereof. The red fluorescent substance produced by the process can be combined with a semiconductor light-emitting element, so as to be used in a light-emitting device or a light-emitting module.

Growing community of inventors

Kawasaki, Japan

Ryosuke Hiramatsu