公开(公告)号：US20240413610A1

公开(公告)日：2024-12-12

申请号：US18699439

申请日：2022-10-24

Applicant: The Regents of the University of California

Inventor： Srinivas Gandrothula ,  Shuji Nakamura ,  Steven P. DenBaars

IPC: H01S5/183 ,  H01S5/02 ,  H01S5/30

Abstract: Methods for fabricating a vertical cavity surface emitting laser (VCSEL) using epitaxial lateral overgrowth (ELO). The ELO layers comprise island-like III-nitride semiconductor layers grown on a substrate using a growth restrict mask, wherein the island-like III-nitride semiconductor layers comprise a light emitting resonant cavity. An aperture for the resonant cavity is fabricated on a wing of the ELO layers with distributed Bragg reflector (DBR) mirrors formed on bottom and top regions of the wing of the ELO layers.

公开(公告)号：US20240405158A1

公开(公告)日：2024-12-05

申请号：US18701367

申请日：2022-10-28

Applicant: The Regents of the University of California

Inventor： Srinivas Gandrothula ,  Shuji Nakamura ,  Steven P. DenBaars

IPC: H01L33/10 ,  H01L33/00 ,  H01L33/22

Abstract: A method for fabricating epitaxial light control features, without reactive ion etching or wet etching, when active layers are included. The epitaxial light control features comprise light extraction or guiding structures integrated on an epitaxial layer of a light emitting device such as a light emitting diode. The light extraction or guiding structures are fabricated on the epitaxial layer using an epitaxial lateral overgrowth (ELO) technique. The epitaxial light control features can have many different shapes and can be fabricated with standard processing techniques, making them highly manufacturable at costs similar to standard processing techniques.

公开(公告)号：US20230420617A1

公开(公告)日：2023-12-28

申请号：US18248817

申请日：2021-10-29

Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA

Inventor： Michael Iza ,  Matthew S. Wong ,  Steven P. DenBaars ,  Shuji Nakamura

IPC: H01L33/42

CPC classification number: H01L33/42 ,  H01L33/32

Abstract: A nitride-based ultraviolet light emitting diode (UVLED) with an ultraviolet transparent contact (UVTC). The nitride-based UVLED is an alloy composition of (Ga, Al, In, B)N semiconductors, and the UVTC is composed of an oxide with a bandgap larger than that emitted in an active region of the nitride-based UVLED, wherein the oxide is an alloy composition of (Ga, Al, In, B, Mg, Fe, Si, Sn)O semiconductors, such as Ga2O3.

公开(公告)号：US11532922B2

公开(公告)日：2022-12-20

申请号：US16652282

申请日：2018-10-02

Applicant: The Regents of the University of California

Inventor： Charles Forman ,  SeungGeun Lee ,  Erin C. Young ,  Jared Kearns ,  Steven P. DenBaars ,  James S. Speck ,  Shuji Nakamura

IPC: H01S5/00 ,  H01S5/183 ,  H01S5/02 ,  H01S5/024 ,  H01S5/30 ,  H01S5/343 ,  H01S5/0234 ,  H01S5/0237 ,  H01S5/02355 ,  H01S5/32 ,  H01S5/10

Abstract: A Vertical Cavity Surface Emitting Laser (VCSEL) including a light emitting III-nitride active region including quantum wells (QWs), wherein each of the quantum wells have a thickness of more than 8 nm, a cavity length of at least 7 λ, or at least 20 λ, where lambda is a peak wavelength of the light emitted from the active region, layers with reduced surface roughness, a tunnel junction intracavity contact. The VCSEL is flip chip bonded using In—Au bonding. This is the first report of a VCSEL capable of continuous wave operation.

公开(公告)号：US20220239068A1

公开(公告)日：2022-07-28

申请号：US17613659

申请日：2020-05-28

Applicant: The Regents of the University of California

Inventor： Jared Kearns ,  Daniel A. Cohen ,  Joonho Back ,  Nathan Palmquist ,  Tal Margalith ,  Steven P. DenBaars ,  Shuji Nakamura

IPC: H01S5/183 ,  H01S5/34 ,  H01S5/343

Abstract: Vertical Cavity Surface Emitting Laser (VCSEL) configurations are disclosed. In a first example, the VCSEL includes a III-Nitride active region between a p-type III-Nitride layer and an n-type III-Nitride layer; and a curved minor on or above the p-type III-Nitride layer. The curved mirror can be formed in a III-Nitride layer or a Transparent Oxide (TO) material and enables the formation of a long VCSEL cavity that improves VCSEL lifetime, VCSEL output power, VCSEL power efficiency and VCSEL reliability. In a second example, the VCSEL has an active region with a high indium content. In a third example, the VCSEL is transparent.

公开(公告)号：US20220181513A1

公开(公告)日：2022-06-09

申请号：US17539345

申请日：2021-12-01

Applicant: The Regents of the University of California

Inventor： Erin C. Young ,  Benjamin P. Yonkee ,  John T. Leonard ,  Tal Margalith ,  James S. Speck ,  Steven P. DenBaars ,  Shuji Nakamura

IPC: H01L33/00 ,  H01L33/32 ,  H01L33/14 ,  H01L21/00 ,  H01L31/0304 ,  C30B23/02 ,  H01L21/02 ,  C30B29/68 ,  H01S5/40 ,  C30B25/20 ,  H01L33/04 ,  C30B29/40 ,  H01S5/30 ,  H01L31/147 ,  H01L33/06

Abstract: A hybrid growth method for III-nitride tunnel junction devices uses metal-organic chemical vapor deposition (MOCVD) to grow one or more light-emitting or light-absorbing structures and ammonia-assisted or plasma-assisted molecular beam epitaxy (MBE) to grow one or more tunnel junctions. Unlike p-type gallium nitride (p-GaN) grown by MOCVD, p-GaN grown by MBE is conductive as grown, which allows for its use in a tunnel junction. Moreover, the doping limits of MBE materials are higher than MOCVD materials. The tunnel junctions can be used to incorporate multiple active regions into a single device. In addition, n-type GaN (n-GaN) can be used as a current spreading layer on both sides of the device, eliminating the need for a transparent conductive oxide (TCO) layer or a silver (Au) mirror.

公开(公告)号：US10985285B2

公开(公告)日：2021-04-20

申请号：US16325246

申请日：2017-08-17

Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA

Inventor： Benjamin P. Yonkee ,  Asad J. Mughal ,  David Hwang ,  Erin C. Young ,  James S. Speck ,  Steven P. DenBaars ,  Shuji Nakamura

IPC: H01L31/0304 ,  H01L29/207 ,  H01L33/32 ,  H01L33/00 ,  H01L21/02 ,  H01L29/36

Abstract: A physical vapor deposition (e.g., sputter deposition) method for III-nitride tunnel junction devices uses metal-organic chemical vapor deposition (MOCVD) to grow one or more light-emitting or light-absorbing structures and electron cyclotron resonance (ECR) sputtering to grow one or more tunnel junctions. In another method, the surface of the p-type layer is treated before deposition of the tunnel junction on the p-type layer. In yet another method, the whole device (including tunnel junction) is grown using MOCVD and the p-type layers of the III-nitride material are reactivated by lateral diffusion of hydrogen through mesa sidewalls in the III-nitride material, with one or more lateral dimensions of the mesa that are less than or equal to about 200 μm. A flip chip display device is also disclosed.

公开(公告)号：US20200244036A1

公开(公告)日：2020-07-30

申请号：US16652282

申请日：2018-10-02

Applicant: The Regents of the University of California

Inventor： Charles Forman ,  SeungGeun Lee ,  Erin C. Young ,  Jared Kearns ,  Steven P. DenBaars ,  James S. Speck ,  Shuji Nakamura

IPC: H01S5/022 ,  H01S5/02 ,  H01S5/024 ,  H01S5/183 ,  H01S5/30 ,  H01S5/343

Abstract: A Vertical Cavity Surface Emitting Laser (VCSEL) including a light emitting III-nitride active region including quantum wells (QWs), wherein each of the quantum wells have a thickness of more than 8 nm, a cavity length of at least 7 λ, or at least 20 λ, where lambda is a peak wavelength of the light emitted from the active region, layers with reduced surface roughness, a tunnel junction intracavity contact. The VCSEL is flip chip bonded using In-Au bonding. This is the first report of a VCSEL capable of continuous wave operation.

公开(公告)号：US20200243334A1

公开(公告)日：2020-07-30

申请号：US16752428

申请日：2020-01-24

Applicant: The Regents of the University of California

Inventor： Christian J. Zollner ,  Michael Iza ,  James S. Speck ,  Shuji Nakamura ,  Steven P. DenBaars

IPC: H01L21/02 ,  H01L29/201 ,  H01L29/20

Abstract: A method for protecting a semiconductor film comprised of one or more layers during processing. The method includes placing a surface of the semiconductor film in direct contact with a surface of a protective covering, such as a separate substrate piece, that forms an airtight or hermetic seal with the surface of the semiconductor film, so as to reduce material degradation and evaporation in the semiconductor film. The method includes processing the semiconductor film under some conditions, such as a thermal annealing and/or controlled ambient, which might cause the semiconductor film's evaporation or degradation without the protective covering.

公开(公告)号：US10217916B2

公开(公告)日：2019-02-26

申请号：US14461151

申请日：2014-08-15

Applicant: The Regents of the University of California

Inventor： Shuji Nakamura ,  Steven P. DenBaars ,  Hirokuni Asamizu

IPC: H01L33/62 ,  H01L33/22 ,  H01L33/54 ,  H01L33/58 ,  G02B19/00 ,  H01L33/38 ,  H01L33/60

Abstract: A transparent light emitting diode (LED) includes a plurality of III-nitride layers, including an active region that emits light, wherein all of the layers except for the active region are transparent for an emission wavelength of the light, such that the light is extracted effectively through all of the layers and in multiple directions through the layers. Moreover, the surface of one or more of the III-nitride layers may be roughened, textured, patterned or shaped to enhance light extraction.