Ulvac, Inc.

Marubun Corporation

Riken Corporation

Toshiba Kikai Kabushiki Kaisha

Tokyo Ohka Kogyo Co., Ltd.

Dai Nippon Printing Co., Ltd.

National Institute of Advanced Industrial Science and Technology

Nippon Tungsten Co., Ltd.

Shibaura Machine Co., Ltd.

Dowa Holdings Co., Ltd.

Yukio Kashima

Takaharu Tashiro

Ryuichiro Kamimura

Yamato Osada

Hideki Hirayama

Eriko Matsuura

Mitsunori Kokubo

Takafumi Ookawa

Toshiro Morita

Satoshi Shimatani

Hideki Takagi

Hiromi Nishihara

Masafumi Jo

Noritoshi Maeda

Sung Won Youn

Yasuhiro Watanabe

Takeshi Iwai

Sachie Fujikawa

Yasushi Iwaisako

Tsugumi Nagano

Kanji Furuta

Yohei Aoyama

A deep ultraviolet LED with a design wavelength &#x3bb;, including a reflecting electrode layer (Au), a metal layer (Ni), a p-GaN contact layer, a p-block layer made of a p-AlGaN layer, an i-guide layer made of an AlN layer, a multi-quantum well layer, an n-AlGaN contact layer, a u-AlGaN layer, an AlN template, and a sapphire substrate that are arranged in this order from a side opposite to the sapphire substrate, in which the thickness of the p-block layer is 52 to 56 nm, a two-dimensional reflecting photonic crystal periodic structure having a plurality of voids is provided in a region from the interface between the metal layer and the p-GaN contact layer to a position not beyond the interface between the p-GaN contact layer and the p-block layer in the thickness direction of the p-GaN contact layer, the distance from an end face of each of the voids in the direction of the sapphire substrate to the interface between the multi-quantum well layer and the i-guide layer satisfies &#x3bb;/2n(where &#x3bb; is the design wavelength and n1Deff is the effective average refractive index of each film of the stacked structure from the end face of each void to the i-guide layer) in the perpendicular direction, the distance being in the range of 53 to 57 nm, the two-dimensional reflecting photonic crystal periodic structure has a photonic band gap that opens for TE polarized components, and provided that the period a of the two-dimensional reflecting photonic crystal periodic structure satisfies a Bragg condition with respect to light with the design wavelength &#x3bb;, the order m of a formula of the Bragg condition: m&#x3bb;/n=2(where m is the order, &#x3bb; is the design wavelength, nis the effective refractive index of two-dimensional photonic crystals, and a is the period of the two-dimensional photonic crystals) satisfies 2&#x2264;m&#x2264;4, and the radius of each void is R, R/a satisfies 0.30&#x2264;R/a&#x2264;0.40.

Deep ultraviolet LED and method for producing the same

Provided is a deep ultraviolet LED with a design wavelength &#x3bb;, including a reflecting electrode layer, an ultra-thin metal layer, and a p-type contact layer that are arranged in this order from a side opposite to a substrate; and a hemispherical lens bonded to a rear surface of the substrate on a side of the p-type contact layer, the hemispherical lens being transparent to light with the wavelength &#x3bb;. The refractive index of the hemispherical lens is greater than or equal to the average value of the refractive index of the substrate and the refractive index of air and is less than or equal to the refractive index of the substrate. The hemispherical lens has a radius that is greater than or equal to the radius of an inscribed circle of the substrate and is about equal to the radius of a circumscribed circle of the substrate.

Deep ultraviolet LED and method for manufacturing the same

The light extraction efficiency of a deep ultraviolet LED is increased. The deep ultraviolet LED has a design wavelength &#x3bb;, and includes, sequentially arranged from a side opposite to a substrate, a reflecting electrode layer, a metal layer, a p-GaN contact layer, a p-AlGaN layer that is transparent to light with the wavelength &#x3bb;, one of a multi-quantum barrier layer or an electron blocking layer, a barrier layer, and a quantum well layer. A thickness of the p-AlGaN layer is less than or equal to 100 nm. A reflecting photonic crystal periodic structure having a plurality of voids is provided in a region in a thickness direction including at least an interface between the p-GaN contact layer and the p-AlGaN layer such that the reflecting photonic crystal periodic structure does not extend beyond the p-AlGaN layer in a direction of the substrate. Maximum light extraction efficiency is obtained when a distance from end faces of the voids in the direction of the substrate to the quantum well layer is greater than or equal to a total thickness of the barrier layer and the multi-quantum barrier layer (or the electron blocking layer) and less than or equal to 80 nm, and a depth h of each void is less than or equal to a total thickness of the p-AlGaN layer and the p-GaN contact layer. The reflecting photonic crystal periodic structure has a photonic band gap that opens for TE polarized components. A period a of the photonic crystal periodic structure satisfies a Bragg condition with respect to light with the design wavelength &#x3bb;. An order m in a formula of the Bragg condition satisfies 1&#x2264;m&#x2264;5. Provided that a radius of each void is R, R/a with which the photonic band gap becomes maximum is satisfied.

Provided is a deep ultraviolet LED with a design wavelength &#x3bb;, including an Al reflecting electrode layer, an ultrathin metal layer, and a transparent p-AlGaN contact layer that are sequentially arranged from a side opposite to a substrate, and a photonic crystal periodic structure provided in the range of the thickness direction of the transparent p-AlGaN contact layer. The photonic crystal periodic structure has a photonic band gap.

A semiconductor light emitting element with a design wavelength of &#x3bb;, comprising a photonic crystal periodic structure having two structures with different refractive indices at each of one or more interfaces between layers that form the light emitting element. The period a and the radius R that are parameters of each of the one or more periodic structures and the design wavelength &#x3bb; satisfy Bragg conditions. The ratio (R/a) between the period a and the radius R is a value determined so that a predetermined photonic band gap (PBG) for TE light becomes maximum for each periodic structure. The parameters of each periodic structure are determined so that light extraction efficiency of the entire semiconductor light emitting element with respect to light with the wavelength &#x3bb; becomes maximum as a result of conducting a simulation analysis with a FDTD method using as variables the depth h of the periodic structure that is of greater than or equal to 0.5a and the period a and the radius R that are determined for each order m of the Bragg conditions.

Semiconductor light emitting element and method for producing the same

A deep ultraviolet LED with a design wavelength of &#x3bb; is provided that includes a reflecting electrode layer, a metal layer, a p-type GaN contact layer, and a p-type AlGaN layer that are sequentially stacked from a side opposite to a substrate, the p-type AlGaN layer being transparent to light with the wavelength of &#x3bb;; and a photonic crystal periodic structure that penetrates at least the p-type GaN contact layer and the p-type AlGaN layer. The photonic crystal periodic structure has a photonic band gap.

A semiconductor light emitting element including, in a light extraction layer thereof, a photonic crystal periodic structure including two systems (structures) with different refractive indices. An interface between the two systems (structures) satisfies Bragg scattering conditions, and the photonic crystal periodic structure has a photonic band gap.

Light emitting element and method for manufacturing same

A method for manufacturing a device having a concavo-convex structure includes forming an organic resist film on an n-type semiconductor layer in which a fine concavo-convex structure is to be formed; forming a silicon-containing resist film on the organic resist film; patterning the silicon-containing resist film by nanoimprint; oxidizing the silicon-containing resist film with oxygen-containing plasma to form a silicon oxide film; dry-etching the organic resist film by using the silicon oxide film as an etching mask; dry-etching the n-type semiconductor layer by using the silicon oxide film and the organic resist film as an etching masks; and removing the silicon oxide film and the organic resist film.

Method for manufacturing device

Growing community of inventors

Tokyo, Japan

Yukio Kashima