Sumitomo Electric Industries, Limited

Sony Corporation

Other

Takamichi Sumitomo

Takashi Kyono

Masaki Ueno

Yohei Enya

Yusuke Yoshizumi

Katsushi Akita

Takao Nakamura

Masahiro Adachi

Shinji Tokuyama

Koji Katayama

Takatoshi Ikegami

Katsunori Yanashima

Kei Fujii

Shimpei Takagi

Suguru Arikata

Hiroshi Nakajima

Susumu Yoshimoto

Kunihiko Tasai

Koji Nishizuka

Takashi Ishizuka

Takeshi Aoki

Yoshihiro Saito

Kazuhide Sumiyoshi

Nobuhiro Saga

Toshiyuki Tanahashi

A vertical cavity surface-emitting laser configured to emit laser light having a wavelength of 830 nm to 910 nm includes a substrate having a main surface including GaAs, a first distributed Bragg reflector, an active layer, and a second distributed Bragg reflector. The substrate, the first distributed Bragg reflector, the active layer, and the second distributed Bragg reflector are arranged in a first axis direction intersecting the main surface. The main surface has an off angle of 6° or more with respect to a (100) plane. The active layer includes InAlGaAs (0<x<1, 0≤y<1). The active layer has a strain. An absolute value of the strain is 0.5% to 1.4%.

Vertical cavity surface-emitting laser

A vertical cavity surface emitting laser includes: an active layer including a quantum well structure including one or more well layers including a III-V compound semiconductor containing indium as a group III constituent element; an upper laminated region containing a carbon dopant; and a substrate for mounting a post including the active layer and the upper laminated region, in which the active layer is provided between the upper laminated region and the substrate, the quantum well structure has a carbon concentration of 2&#xd7;10cmor less, and the upper laminated region includes a pile-up layer of indium at a position away from the active layer.

Vertical cavity surface emitting laser and method for manufacturing vertical cavity surface emitting laser

A vertical cavity surface emitting laser includes: a supporting base having a principal surface including III-V compound semiconductor containing gallium and arsenic as constituent elements; and a post disposed on the principal surface. The post has a lower spacer region including a III-V compound semiconductor containing gallium and arsenic as group-III elements, and an active layer having a quantum well structure disposed on the lower spacer region. The quantum well structure has a concentration of carbon in a range of 2&#xd7;10cmor more to 5&#xd7;10cmor less. The quantum well structure includes a well layer and a barrier layer. The well layer includes a III-V compound semiconductor containing indium as a group-III element, and the barrier layer includes a III-V compound semiconductor containing indium and aluminum as group-III elements. The lower spacer region is disposed between the supporting base and the active layer.

Vertical cavity surface emitting laser, method for fabricating vertical cavity surface emitting laser

A group III nitride semiconductor laser device includes a laser structure, an insulating layer, an electrode and dielectric multilayers. The laser structure includes a semiconductor region on a semi-polar primary surface of a hexagonal group III nitride semiconductor support base. The dielectric multilayers are on first and second end-faces for the laser cavity. The c-axis of the group III nitride tilts by an angle ALPHA from the normal axis of the primary surface in the waveguide axis direction from the first end-face to the second end-faces. A pad electrode has first to third portions provided on the first to third regions of the semiconductor regions, respectively. An ohmic electrode is in contact with the third region through an opening of the insulating layer. The first portion has a first arm, which extends to the first end-face edge. The third portion is away from the first end-face edge.

Group III nitride semiconductor light emitting device

A Group III nitride semiconductor laser device includes a laser structure including a support substrate with a semipolar primary surface of a hexagonal Group III nitride semiconductor, and a semiconductor region thereon, and an electrode, provided on the semiconductor region, extending in a direction of a waveguide axis in the laser device. The c-axis of the nitride semiconductor is inclined at an angle ALPHA relative to a normal axis to the semipolar surface toward the waveguide axis direction. The laser structure includes first and second fractured faces intersecting with the waveguide axis. A laser cavity of the laser device includes the first and second fractured faces extending from edges of first and second faces. The first fractured face includes a step provided at an end face of an InGaN layer of the semiconductor region and extending in a direction from one side face to the other of the laser device.

III-nitride semiconductor laser device and method for fabricating III-nitride semiconductor laser device

A group III nitride semiconductor optical devicehas a group III nitride semiconductor substratehaving a main surfaceforming a finite angle with a reference plane Sc orthogonal to a reference axis Cx extending in a c-axis direction of the group III nitride semiconductor and an active layerof a quantum-well structure, disposed on the main surfaceof the group III nitride semiconductor substrate, including a well layermade of a group III nitride semiconductor and a plurality of barrier layersmade of a group III nitride semiconductor. The main surfaceexhibits semipolarity. The active layerhas an oxygen content of at least 1&#xd7;10cmbut not exceeding 8&#xd7;10cm. The plurality of barrier layerscontain an n-type impurity other than oxygen by at least 1&#xd7;10cmbut not exceeding 1&#xd7;10cmin an upper near-interface areain contact with a lower interfaceSd of the well layeron the group III nitride semiconductor substrate side.

Group III nitride semiconductor optical device

A nitride semiconductor laser comprises a conductive support base having a primary surface of gallium nitride based semiconductor, an active layer on the primary surface, and a p-type cladding region on the primary surface. The primary surface is tilted to a reference plane perpendicular to a reference axis extending in the c-axis direction of the gallium nitride based semiconductor. The p-type cladding region comprises a first p-type group III nitride semiconductor layer of an AlGaN layer anisotropically-strained, and a second p-type group III nitride semiconductor layer of material different from the AlGaN layer. The first p-type group III nitride semiconductor layer is provided between the second p-type group III nitride semiconductor layer and the active layer. The AlGaN layer has the largest bandgap in the p-type cladding region. The second p-type group III nitride semiconductor layer has a resistivity lower than the first p-type group III nitride semiconductor layer.

Nitride semiconductor laser, epitaxial substrate

Provided is a Group III nitride semiconductor device, which comprises an electrically conductive substrate including a primary surface comprised of a first gallium nitride based semiconductor, and a Group III nitride semiconductor region including a first p-type gallium nitride based semiconductor layer and provided on the primary surface. The primary surface of the substrate is inclined at an angle in the range of not less than 50 degrees, and less than 130 degrees from a plane perpendicular to a reference axis extending along the c-axis of the first gallium nitride based semiconductor, an oxygen concentration Noxg of the first p-type gallium nitride based semiconductor layer is not more than 5&#xd7;10cm, and a ratio (Noxg/Npd) of the oxygen concentration Noxg to a p-type dopant concentration Npd of the first p-type gallium nitride based semiconductor layer is not more than 1/10.

Group-III nitride semiconductor device, method for fabricating Group-III nitride semiconductor device, and epitaxial substrate

A nitride-based semiconductor light-emitting element LEor LDhas: a gallium nitride substratehaving a principal surfacewhich makes an angle &#x3b1;, in the range 40&#xb0; to 50&#xb0; or in the range more than 90&#xb0; to 130&#xb0;, with the reference plane Sc perpendicular to the reference axis Cx extending in the c axis direction; an n-type gallium nitride-based semiconductor layer; a second gallium nitride-based semiconductor layer; and a light-emitting layerincluding a plurality of well layers of InGaN and a plurality of barrier layersof a GaN-based semiconductor, wherein the direction of piezoelectric polarization of the plurality of well layersis the direction from the n-type gallium nitride-based semiconductor layertoward the second gallium nitride-based semiconductor layer

Nitride-based semiconductor light-emitting element

For a nitride semiconductor light emitting device, a c-axis vector of hexagonal GaN of a support substrate is inclined to an X-axis direction with respect to a normal axis Nx normal to a primary surface. In a semiconductor region an active layer, a first gallium nitride-based semiconductor layer, an electron block layer, and a second gallium nitride-based semiconductor layer are arranged along the normal axis on the primary surface of the support substrate. A p-type cladding layer is comprised of AlGaN, and the electron block layer is comprised of AlGaN. The electron block layer is subject to tensile strain in the X-axis direction. The first gallium nitride-based semiconductor layer is subject to compressive strain in the X-axis direction. The misfit dislocation density at an interface is smaller than that at an interface. A barrier to electrons at the interface is raised by piezoelectric polarization.

Nitride semiconductor light emitting device and epitaxial substrate

Provided is a group-III nitride semiconductor laser device with a laser cavity of high lasing yield, on a semipolar surface of a support base in which the c-axis of a hexagonal group-III nitride is tilted toward the m-axis. First and second fractured faces to form the laser cavity intersect with an m-n plane. The group-III nitride semiconductor laser device has a laser waveguide extending in a direction of an intersecting line between the m-n plane and the semipolar surface. In a laser structure, a first surface is opposite to a second surface. The first and second fractured faces extend from an edge of the first surface to an edge of the second surface. The fractured faces are not formed by dry etching and are different from conventionally-employed cleaved facets such as c-planes, m-planes, or a-planes.

Group-III nitride semiconductor laser device, and method for fabricating group-III nitride semiconductor laser device

A nitride semiconductor laser includes an electrically conductive support substrate with a primary surface of a gallium nitride based semiconductor, an active layer provided above the primary surface, and a p-type cladding region provided above the primary surface. The primary surface is inclined relative to a reference plane perpendicular to a reference axis extending in a direction of the c-axis of the gallium nitride based semiconductor. The p-type cladding region includes first and second p-type Group III nitride semiconductor layers. The first p-type semiconductor layer comprises an InAlGaN layer including built-in anisotropic strain. The second p-type semiconductor layer comprises semiconductor different from material of the InAlGaN layer. The first nitride semiconductor layer is provided between the second p-type semiconductor layer and the active layer. The second p-type semiconductor layer has a resistivity lower than that of the first p-type semiconductor layer.

Nitride semiconductor laser and epitaxial substrate

Provided is a group-III nitride semiconductor laser device with a laser cavity allowing for a low threshold current, on a semipolar surface of a support base in which the c-axis of a hexagonal group-III nitride is tilted toward the m-axis. First and second fractured facesto form the laser cavity intersect with an m-n plane. The group-III nitride semiconductor laser devicehas a laser waveguide extending in a direction of an intersecting line between the m-n plane and the semipolar surface. For this reason, it is feasible to make use of emission by a band transition enabling the low threshold current. In a laser structure, a first surfaceis opposite to a second surface. The first and second fractured facesextend from an edgeof the first surfaceto an edgeof the second surface. The fractured faces are not formed by dry etching and are different from conventionally-employed cleaved facets such as c-planes, m-planes, or a-planes.

A group III nitride substrate has a semi-polar primary surface. A first cladding layer has a first conductivity type, and comprises aluminum-containing group III nitride. The first cladding layer is provided on the substrate. An active layer is provided on the first cladding layer. A second cladding layer has a second conductivity type, and comprises aluminum-containing group III nitride. The second cladding layer is provided on the active layer. An optical guiding layer is provided between the first cladding layer and the active layer and/or between the second cladding layer and the active layer. The optical guiding layer comprises a first layer comprising InGaN (0&#x2266;x1&#x3c;1) and a second layer comprising InGaN (x1&#x3c;x2&#x3c;1). The second layer is provided between the first layer and the active layer. The total thickness of the first layer and the second layer is greater than 0.1 &#x3bc;m. The wavelength of laser light is in a range of 480 nm to 550 nm.

Group III nitride semiconductor laser diode

Provided is a group-III nitride semiconductor laser device with a laser cavity allowing for a low threshold current, on a semipolar surface of a support base in which the c-axis of a hexagonal group-III nitride is tilted toward the m-axis. First and second fractured facesto form the laser cavity intersect with an m-n plane. The group-III nitride semiconductor laser devicehas a laser waveguide extending in a direction of an intersecting line between the m-n plane and the semipolar surface. In a laser structure, a first surfaceis opposite to a second surface. The first and second fractured facesextend from an edgeof the first surface to an edgeof the second surface. The fractured faces are not formed by dry etching and are different from conventionally-employed cleaved facets such as c-planes, m-planes, or a-planes.

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Itami, Japan

Takamichi Sumitomo