公开(公告)号：US12074254B2

公开(公告)日：2024-08-27

申请号：US17271173

申请日：2019-08-30

Applicant: OSAKA UNIVERSITY

Inventor： Shuhei Ichikawa ,  Yasufumi Fujiwara ,  Jun Tatebayashi

IPC: H01L33/32 ,  H01L33/00 ,  H01L33/02 ,  H01L33/16

CPC classification number: H01L33/325 ,  H01L33/007 ,  H01L33/0075 ,  H01L33/025 ,  H01L33/16

Abstract: The purpose of the present invention is to provide a technique of manufacturing a nitride semiconductor layer with which, when producing a semiconductor device by forming a nitride semiconductor layer on off-angle inclined substrate, it is possible to stably supply high-quality semiconductor devices by preventing occurrence of a macro step using a material that is not likely to occur lattice strains or crystal defects by mixing with GaN and does not require continuous addition; and provided is a nitride semiconductor device which comprises a nitride semiconductor layer formed on a substrate, wherein the substrate is inclined at an off angle, a rare earth element-added nitride layer to which a rare earth element is added is formed on the substrate as a primed layer, and a nitride semiconductor layer is formed on the rare earth element-added nitride layer.

公开(公告)号：US11075322B2

公开(公告)日：2021-07-27

申请号：US16486556

申请日：2018-02-26

Applicant: OSAKA UNIVERSITY

Inventor： Yasufumi Fujiwara ,  Tomohiro Inaba

IPC: H01L33/32 ,  H01L33/00 ,  H01L33/04

Abstract: Provided is a technique for manufacturing a semiconductor light-emitting element for which it is possible to dramatically increase light emission efficiency to a greater degree than in the past. An AlInN film provided on a GaN epitaxial film that is formed on a substrate, wherein: the AlInN film is formed by lamination of AlInN layers; between the laminated AlInN layers, there is provided a cap layer that comprises GaN, AlN, or AlGaN, and has a thickness of 0.1-10 nm; a super lattice structure is formed; the total thickness exceeds 200 nm; and the root-mean-square height RMS is 3 nm or less. A method for forming an AlInN film, the method being such that: a step for forming an AlInN layer is repeated a plurality of times, said step involving using any of an organometallic vapor phase growth method, a molecular beam epitaxy method, and a sputtering method to form the AlInN layer to a thickness of 200 nm or less by epitaxial growth in an atmosphere of 700-850° C. on a GaN epitaxial film formed on a substrate; and the AlInN layer is grown until a prescribed thickness is reached.

公开(公告)号：US20150214434A1

公开(公告)日：2015-07-30

申请号：US14422185

申请日：2013-08-01

Applicant: OSAKA UNIVERSITY

Inventor： Yasufumi Fujiwara ,  Atsushi Koizumi ,  Yoshikazu Terai

IPC: H01L33/32 ,  H01L33/24 ,  H01L33/00

CPC classification number: H01L33/325 ,  H01L21/0242 ,  H01L21/02458 ,  H01L21/0254 ,  H01L21/02581 ,  H01L21/0262 ,  H01L21/02639 ,  H01L21/02647 ,  H01L33/0075 ,  H01L33/16 ,  H01L33/24

Abstract: A production method of a substrate for nitride semiconductor device comprising a mask formation step of using a metal nitride as a base material and forming a mask having a prescribed shape on the above-described base material, a three-dimensional structure growth step of growing a three-dimensional structure made of the same material as the base material on the base material having the mask formed thereon using a selective growth technique so that a layer having a higher index plane is formed on the lateral face, and an active layer growth step of growing an active layer containing a rare earth element on the lateral face of the above-described three-dimensional structure using an organometallic vapor phase epitaxial method.

Abstract translation: 一种氮化物半导体器件用基板的制造方法，其特征在于，具有使用金属氮化物作为基材并在上述基材上形成具有规定形状的掩模的掩模形成工序的三维结构生长工序， 使用选择生长技术在其上形成有掩模的基材上与基材相同的材料制成三维结构，使得在侧面上形成具有较高折射率的层，以及活性层生长步骤 使用有机金属气相外延法在上述三维结构的侧面上生长含有稀土元素的活性层。

公开(公告)号：US12068432B2

公开(公告)日：2024-08-20

申请号：US17343239

申请日：2021-06-09

Applicant: OSAKA UNIVERSITY

Inventor： Yasufumi Fujiwara ,  Takeshi Uenoyama ,  Jun Tatebayashi ,  Shuhei Ichikawa

IPC: H01L33/08 ,  H01L33/00 ,  H01L33/10 ,  H01L33/24 ,  H01L33/32 ,  H01L33/62

CPC classification number: H01L33/08 ,  H01L33/0025 ,  H01L33/10 ,  H01L33/24 ,  H01L33/325 ,  H01L33/62

Abstract: Provided is a display device including a light emitting unit that can emit a plurality of types of light having different wavelengths to the outside at a desired ratio with high intensity without increasing manufacturing costs in proportion to a number of pixels even when the number of pixels increases. Provided is a display device including a light emitting unit in which a plurality of types of PiN junction-type light emitting diodes that emit light having different wavelengths are arranged on the same substrate, and at least one type among the plurality of types of light emitting diodes has an active layer containing a rare earth element. Provided is a display device in which a plurality of types of light emitting diodes are sequentially stacked on the surface of a substrate, and a light emitting layer for one color is formed to overlap at least a portion of a light emitting layer for another color.

公开(公告)号：US11133435B2

公开(公告)日：2021-09-28

申请号：US16463765

申请日：2017-11-20

Applicant: OSAKA UNIVERSITY

Inventor： Yasufumi Fujiwara ,  Wanxin Zhu ,  Atsushi Koizumi ,  Brandon Mitchell ,  Tom Gregorkiewicz

IPC: H01L33/12 ,  C30B29/40 ,  C30B25/02 ,  C23C16/34 ,  H01L29/15 ,  H01L29/20 ,  H01L33/04 ,  H01L33/00 ,  H01L21/02 ,  H01L33/32 ,  H01L21/205 ,  C30B29/38 ,  H01S5/323

Abstract: Provided is a technique for manufacturing a nitride semiconductor substrate with which it is possible to manufacture a nitride semiconductor substrate having sufficiently reduced dislocation density with a large area even if manufactured on an inexpensive substrate made of sapphire, etc. A nitride semiconductor substrate in which a nitride semiconductor layer formed on a substrate is formed by laminating an undoped nitride layer and a rare earth element-added nitride layer to which a rare earth element is added as a doping material, and the dislocation density is of the order of 106 cm−2 or less. A method for manufacturing a nitride semiconductor substrate in which a step for growing GaN, InN, AlN, or a mixed crystal of two or more thereof on a substrate to form an undoped nitride layer, and a step for forming a rare earth element-added nitride layer to which a rare earth element is added so as to be substituted for Ga, In, or Al are performed via a series of formation steps using an organic metal vapor epitaxial technique at a temperature of 900 to 1200° C. without extraction from a reaction vessel.

公开(公告)号：US20210091268A1

公开(公告)日：2021-03-25

申请号：US16848175

申请日：2020-04-14

Applicant: Lehigh University ,  Osaka University

Inventor： Volkmar Dierolf ,  Brandon Mitchell ,  Ruoqiao Wei ,  Yasufumi Fujiwara ,  Tomasz Gregorkiewicz ,  Shuhei Ichikawa ,  Jun Tatebayashi ,  Dolf Timmerman

IPC: H01L33/32 ,  H01L33/06 ,  H01L33/12 ,  H01L33/50 ,  H01L25/075 ,  H01L33/08

Abstract: A color tunable light emission diode in which the color tone of the emission color changes by controlling the injection current, which has an active layer sandwiched between a p-type layer and an n-type layer on a substrate, and the active color layer is formed by doping Eu and Mg to an AlGaInN-based material which is GaN, InN, AlN or a mixed crystal of any two or more of them; and a micro LED display, wherein its display unit is formed by integrating image pixels having the above color tunable light emission diode are provided; and a light emitting semiconductor device technology capable of providing an ultra-small and high definition micro LED display can be provided.

公开(公告)号：US09455376B2

公开(公告)日：2016-09-27

申请号：US14422185

申请日：2013-08-01

Applicant: OSAKA UNIVERSITY

Inventor： Yasufumi Fujiwara ,  Atsushi Koizumi ,  Yoshikazu Terai

IPC: H01L31/0256 ,  H01L33/32 ,  H01L33/16 ,  H01L21/02 ,  H01L33/00 ,  H01L33/24

CPC classification number: H01L33/325 ,  H01L21/0242 ,  H01L21/02458 ,  H01L21/0254 ,  H01L21/02581 ,  H01L21/0262 ,  H01L21/02639 ,  H01L21/02647 ,  H01L33/0075 ,  H01L33/16 ,  H01L33/24

Abstract: A production method of a substrate for nitride semiconductor device comprising a mask formation step of using a metal nitride as a base material and forming a mask having a prescribed shape on the above-described base material, a three-dimensional structure growth step of growing a three-dimensional structure made of the same material as the base material on the base material having the mask formed thereon using a selective growth technique so that a layer having a higher index plane is formed on the lateral face, and an active layer growth step of growing an active layer containing a rare earth element on the lateral face of the above-described three-dimensional structure using an organometallic vapor phase epitaxial method.