Abstract: The present invention relates to: a dopant for an organic optoelectronic device, represented by chemical formula 1; an organic optoelectronic device including the dopant; and a display device.

Abstract: The device according to the invention comprises a nanostructured LED with a first group of nanowires protruding from a first area of a substrate and a contacting means in a second area of the substrate. Each nanowire of the first group of nanowires comprises a p-i-n-junction and a top portion of each nanowire or at least one selection of nanowires is covered with a light-reflecting contact layer. The contacting means of the second area is in electrical contact with the bottom of the nanowires, the light-reflecting contact layer being in electrical contact with the contacting means of the second area via the p-i-n-junction. Thus when a voltage is applied between the contacting means of the second area and the light-reflecting contact layer, light is generated within the nanowire. On top of the light-reflecting contact layer, a first group of contact pads for flip-chip bonding can be provided, distributed and separated to equalize the voltage across the layer to reduce the average serial resistance.

Abstract: Provided is a large diameter InP single crystal substrate having a diameter of 75 mm or more, which can achieve a high electrical activation rate of Zn over a main surface of the substrate even in a highly doped region having a Zn concentration of 5×1018 cm?3 or more; and a method for producing the same. An InP single crystal ingot is cooled such that a temperature difference of 200° C. is decreased for 2 to 7.5 minutes, while rotating the InP single crystal ingot at a rotation speed of 10 rpm or less, and the cooled InP single crystal ingot is cut into a thin plate, thereby allowing production of the InP single crystal substrate having an electrical activation rate of Zn of more than 85% over the main surface of the substrate even in a highly doped region having a Zn concentration of 5×1018 cm?3 or more.

Abstract: An object is to provide a light-emitting display device in which a pixel including a thin film transistor using an oxide semiconductor has a high aperture ratio. The light-emitting display device includes a plurality of pixels each including a thin film transistor and a light-emitting element. The pixel is electrically connected to a first wiring functioning as a scan line. The thin film transistor includes an oxide semiconductor layer over the first wiring with a gate insulating film therebetween. The oxide semiconductor layer is extended beyond the edge of a region where the first wiring is provided. The light-emitting element and the oxide semiconductor layer overlap with each other.

Abstract: 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?O8nm/O3nm?0.5 is satisfied, where O3nm (at %) is the oxygen concentration at a depth of 3 nm of the buffer layer, and O8nm (at %) is the oxygen concentration at a depth of 8 nm of the buffer layer.

Abstract: The present invention relates to a display device and, more particularly, to a display device using a semiconductor light emitting element. The display device according to the present invention comprises: a substrate including a plurality of metal pads; and a green semiconductor light emitting element and a blue semiconductor light emitting element, which are electrically connected to the metal pads through self-assembly, wherein the green semiconductor light emitting element and the blue semiconductor light emitting element include identification parts having different shapes so as to be distinguishable from each other when connected to the substrate.

Abstract: Disclosed herein is a method comprising: determining a first waveform of electric voltage based on a history of operation of an electroluminescent device, the history of operation comprising one or more parameters selected from the group consisting of durations of light emission of the electroluminescent device, intensities of light emission of the electroluminescent device, temperatures of the electroluminescent device during light emission, and combinations thereof; applying the first waveform of electric voltage to the electroluminescent device.

Abstract: A light-emitting electrochemical cell has a light-emitting layer and electrodes and disposed on the respective surface thereof. The light-emitting layer includes an organic polymeric light-emitting material and an ionic compound represented by the general formula (1). The ring A1 denotes an aromatic ring; X is S, C or P; R1 denotes R? or OR?, and R? denotes an alkyl group; n denotes 0 or 1; B denotes O, OR2 or A2, R2 denotes a saturated hydrocarbon group, and A2 denotes an aromatic ring; the bond a is a single bond or a double bond; the bond a between B and X is a double bond and B is O; when X is P, the bond a between B and X is a single bond and B is OR2 or A2; d is 1 or more; and Y+ denotes a cation.

Abstract: Disclosed is a wafer or a material stack for semiconductor-based optoelectronic or electronic devices that minimizes or reduces misfit dislocation, as well as a method of manufacturing such wafer of material stack. A material stack according to the disclosed technology includes a substrate; a basis buffer layer of a first material disposed above the substrate; and a plurality of composite buffer layers disposed above the basis buffer layer sequentially along a growth direction. The growth direction is from the substrate to a last composite buffer layer of the plurality of composite buffer layers. Each composite buffer layer except the last composite buffer layer includes a first buffer sublayer of the first material, and a second buffer sublayer of a second material disposed above the first buffer sublayer. The thicknesses of the first buffer sublayers of the composite buffer layers decrease along the growth direction.

Abstract: In one aspect, solid-state organic intermediate-band photovoltaic devices are provided. A solid-state organic intermediate-band photovoltaic device, in some embodiments, comprises an organic electron donor and an organic electron acceptor, wherein the organic electron donor comprises a singlet energy level separated from a triplet energy level by an energy gap. The device also comprises a triplet sensitizer comprising singlet and triplet energy levels falling within the singlet-triplet energy gap of the electron donor.

Abstract: To provide a high-quality group III nitride semiconductor. A group III nitride semiconductor including an n-GaN layer composed of AlxGa1-xN (0?x<1), an InGaN layer disposed on the n-GaN layer and composed of InGaN, an n-AlGaN layer disposed on the InGaN layer and composed of n-type AlyGa1-yN (0?y<1), and a functional layer disposed on the n-AlGaN layer, wherein the concentration of Mg in the n-GaN layer is higher than the concentration of Mg in the n-AlGaN layer.

Abstract: A light emitting composition comprising a central platinum group transition metal and a bidentate ligand comprised of at least one pyridyl group with an electron donating substituent in the 4 position forming a six membered ring complex. The electron donating substituent is represented by an alkyl, aryl or amine group. The platinum group transition metal may be selected from the group consisting of platinum, palladium, iridium, rhodium, ruthenium, and osmium. Additionally, OLED devices are provided, each of the OLED devices comprising a light emitting layer that includes one of the light emitting compositions.

Abstract: A semiconductor device includes a substrate and a p-doped layer including a doped III-V material on the substrate. An n-type material is formed on or in the p-doped layer. The n-type material includes an oxide of a II-VI material. An oxygen scavenging interlayer is formed on the n-type material. An aluminum contact is formed in direct contact with the oxygen scavenging interlayer to form an electronic device.

Abstract: In embodiments of the invention, a light emitting device includes a semiconductor structure including a light emitting layer disposed between an n-type region and a p-type region. A first wavelength converting layer is disposed in a path of light emitted by the light emitting layer. The first wavelength converting layer may be a wavelength converting ceramic. A second wavelength converting layer is fused to the first wavelength converting layer. The second wavelength converting layer may be a wavelength converting material disposed in glass.

Abstract: In one aspect, solid-state organic intermediate-band photovoltaic devices are provided. A solid-state organic intermediate-band photovoltaic device, in some embodiments, comprises an organic electron donor and an organic electron acceptor, wherein the organic electron donor comprises a singlet energy level separated from a triplet energy level by an energy gap. The device also comprises a triplet sensitizer comprising singlet and triplet energy levels falling within the singlet-triplet energy gap of the electron donor.

Abstract: In a deep ultraviolet light-emitting device comprising a Group III nitride semiconductor, the concentrations of electrons and holes injected into a light-emitting layer is improved. A barrier layer has a last barrier layer closest to an electron blocking layer. The electron blocking layer has a first electron blocking layer closest to a light-emitting layer. The last barrier layer has a first position farthest from the first electron blocking layer, and a second position as an interface with the first electron blocking layer. The first electron blocking layer has a third position farthest from the last barrier layer. The Al composition ratio at the first position is higher than the Al composition ratio at the second position. The Al composition ratio at the third position is higher than the Al composition ratio at the first and second positions.

Abstract: The invention generally relates to materials and methods for creating and/or utilizing upconverting luminescence. More particularly, the invention relates to novel compositions (e.g., nanoparticles) and related methods of preparation and use that enable upconverting luminescence with an efficient excitation optimized at about 800 nm. A unique class of cascade sensitized tri-doped UCNPs with a biocompatiable 800 nm excitable property are disclosed herein, for example, tri-doped ?-NaYF4:Nd, Yb, Er (Tm)/NaYF4UCNPs, which employ Nd3+ as 800 nm photon sensitizer and Yb3+ as bridging ions, having strong green or blue upconversion emissions without photobleaching.

Abstract: A semiconductor device includes an upper and lower mirror. At least one active region for light generation is between the upper and lower mirror. At least one cavity spacer layer is between at least one of the upper and lower mirror and the active region. The device includes an inner mode confinement region and an outer current blocking region. A depleted heterojunction current blocking region (DHCBR) including a depleting impurity is within the outer current blocking region of ?1 of the upper mirror, lower mirror, and the first active region. A middle layer including a conducting channel is within the inner mode confinement region that is framed by the DHCBR. The DHCBR forces current flow into the conducting channel during normal operation of the light source.

Abstract: A liquid crystal display device containing a liquid crystal panel that includes a first substrate, a second substrate, and first and second polarizers at respective outer surfaces of the first and second substrates; and a backlight unit under the liquid crystal panel that includes a light source, wherein the light source includes a first luminous body having a first peak wavelength, a second luminous body having a second peak wavelength greater than the first peak wavelength, and a third luminous body having a third peak wavelength greater than the second peak wavelength, and wherein the first polarizer contains a light absorption layer having an absorption peak between the second peak wavelength and the third peak wavelength.

Abstract: A technique of manufacturing a display device with high productivity is provided. In addition, a high-definition display device with high color purity is provided. By adjusting the optical path length between an electrode having a reflective property and a light-emitting layer by the central wavelength of a wavelength range of light passing through a color filter layer, the high-definition display device with high color purity is provided without performing selective deposition of light-emitting layers. In a light-emitting element, a plurality of light-emitting layers emitting light of different colors are stacked. The closer the light-emitting layer is positioned to the electrode having a reflective property, the shorter the wavelength of light emitted from the light-emitting layer is.

Abstract: Novel phosphorescent metal complexes containing 2-phenylisoquinoline ligands with at least two substituents on the isoquinoline ring are provided. The disclosed compounds have low sublimation temperatures that allow for ease of purification and fabrication into a variety of OLED devices.

Abstract: The present invention pertains to a group III-V compound semiconductor nanowire able to be used in a group III-V compound semiconductor MOSFET (FET) operational at a small subthreshold (100 mV/dec or less). A side face of the group III-V compound semiconductor nanowire is a (?110) plane constituted of a very small (111) plane. The group III-V compound semiconductor nanowire has, e.g., a first layer having a (111)A plane as a side face thereof, and a second layer having a (111)B plane as a side face thereof. The first layer and the second layer are stacked alternatingly in the axial direction.

Abstract: Systems and methods related to the arrangement of regions containing wavelength-converting materials, and associated articles, are provided.

Abstract: A hybrid light emitting diode (LED) display and fabrication method are provided. The method forms a stack of thin-film layers overlying a top surface of a substrate. The stack includes an LED control matrix and a plurality of pixels. Each pixel is made up of a first subpixel enabled using an inorganic micro LED (uLED), a second subpixel enabled using an organic LED (OLED), and a third subpixel enabled using an OLED. The first subpixel emits a blue color light, the second subpixel emits a red color light, and the third subpixel emits a green color light. In one aspect, the stack includes a plurality of wells in a top surface of the stack, populated by the LEDs. The uLEDs may be configured vertical structures with top and bottom electrical contacts, or surface mount top surface contacts. The uLEDs may also include posts for fluidic assembly orientation.

Abstract: A nitride semiconductor device includes: a substrate having a first major surface and a second major surface; a first nitride semiconductor layer of an n-type which is disposed on the first major surface and has a protrusion; a second nitride semiconductor layer of a p-type disposed on the protrusion; a first anode electrode disposed above the first nitride semiconductor layer and the second nitride semiconductor layer; and a cathode electrode disposed under the second major surface, and a lateral surface of the protrusion is inclined by a first angle with respect to the first major surface.

Abstract: A group III nitride semiconductor light emitting element includes an active layer between an n-type layer and a p-type layer, having an n-electrode on the n-type layer and a p-electrode on the p-type layer, and having a mesa structure containing the p-type layer. In a top view of the group III nitride semiconductor light emitting element, the distance between a portion of an end part of the mesa structure and the periphery of the p-electrode is ? or more of a diffusion length Ls.

Abstract: A display device includes a display panel including a plurality of pixels, the display panel having a display area with the pixels thereon and a peripheral area adjacent to the display area on a plane, a driving circuit part at the peripheral area and configured to provide an electrical signal to each of the pixels, a main circuit part at the peripheral area, the main circuit part having at least one portion that is spaced apart from the driving circuit part on a plane, the main circuit part being configured to provide a driving signal to the driving circuit part and the display panel, and a first partition member at a space between the main circuit part and the driving circuit part.

Abstract: A semiconductor structure has a nano-crystalline core comprising a first semiconductor material and a nano-crystalline shell comprising a second, different semiconductor material at least partially surrounding the nano-crystalline core. Either one, but not both, of the core and shell are based on cadmium-containing semiconductor materials.

Abstract: The present disclosure provides a mobile machine including a laser diode based lighting system having an integrated package holding at least a gallium and nitrogen containing laser diode and a wavelength conversion member. The gallium and nitrogen containing laser diode is configured to emit a first laser beam with a first peak wavelength. The wavelength conversion member is configured to receive at least partially the first laser beam with the first peak wavelength to excite an emission with a second peak wavelength that is longer than the first peak wavelength and to generate the white light mixed with the second peak wavelength and the first peak wavelength. The mobile machine further includes a light detection and ranging (LIDAR) system configured to generate a second laser beam and manipulate the second laser beam to sense a spatial map of target objects in a remote distance.

Abstract: An organic compound having a high T1 level is provided. An element emitting phosphorescence in the blue and green regions is provided. An organic compound having a high glass-transition temperature is provided. A light-emitting element, a light-emitting device, an electronic appliance, or a lighting device having high heat resistance is provided. A light-emitting element includes at least a hole-transport layer, a light-emitting layer, and an electron-transport layer between an anode and a cathode. An anthracene compound represented by General Formula (G1) is contained in at least one of the hole-transport layer, the light-emitting layer, and the electron-transport layer.

Abstract: In a light emitting section, a phosphor layer including a first phosphor particle which receives excitation light and emits fluorescence with a first peak wavelength and a phosphor layer including a second phosphor particle which receives the excitation light and emits fluorescence with a second peak wavelength are stacked. In the light emitting section, when an upper surface is a surface from which illumination light is mostly emitted, the illumination light including the fluorescence emitted from the first phosphor particle and the fluorescence emitted from the second phosphor particle, a reflective member to reduce leakage of fluorescence is provided on a side surface of the light emitting section.

Abstract: A semiconductor optical device has a multilayer structure 30 including a first compound semiconductor layer 31, an active layer 33, and a second compound semiconductor layer 32. A second electrode 42 is formed on the second compound semiconductor layer 32 through a contact layer 34. The contact layer 34 has a thickness of four or less atomic layers. When an interface between the contact layer 34 and the second compound semiconductor layer 32 is an xy-plane, a lattice constant along an x-axis of crystals constituting an interface layer 32A which is a part of the second compound semiconductor layer in contact with the contact layer 34 is x2, a lattice constant along a z-axis is z2, a length along an x-axis in one unit of crystals constituting the contact layer 34 is xc?, and a length along the z-axis is zc?, (zc?/xc?)>(z2/x2) is satisfied.

Abstract: Organic metal compounds, and organic light-emitting devices employing the same, are provided. The organic metal compound has a chemical structure represented by formula (I): wherein each R1 can be independently hydrogen, C1-12 alkyl group, C5-10 cycloalkyl group, C3-12 heteroaryl group, or C6-12 aryl group; R2 can be independently hydrogen, halogen, C1-12 alkyl group, C5-10 cycloalkyl group, C3-12 heteroaryl group, or C6-12 aryl group.

Abstract: A semiconductor device includes a substrate and a p-doped layer including a doped III-V material on the substrate. An n-type material is formed on or in the p-doped layer. The n-type layer includes ZnO. An aluminum contact is formed in direct contact with the ZnO of the n-type material to form an electronic device.

Abstract: A diode pumped solid state laser is provided which includes a ruby crystal optical gain medium and a high bandgap semiconductor laser diode (LD) or light emitting diode (LED) pump source to directly optically pump the gain medium. The high-bandgap semiconductor LD or LED is a semiconductor device whose chemical composition is chosen to provide output radiation at an approximate wavelength of ˜405 nm. The ruby crystal produces laser output at the relatively short wavelength of ˜694 nm.

Abstract: An electrical leakage detection apparatus includes a microcomputer and a relay. The microcomputer is configured to perform an electrical leakage diagnosis to determine whether or not a direct-current leakage exists from a secondary battery that provides and receives electricity to/from an alternating-current power system that includes an electrical leakage detector that detects an alternating-current leakage of alternating-current power supplied from a utility power source. The relay disconnectably connects the secondary battery with the microcomputer.

Abstract: One objective of the present invention is to provide a coating liquid for forming a light emitting layer, which improves quantum efficiency. Another objective of the present invention is to provide: an organic electroluminescent element which is formed by means of this coating liquid for forming a light emitting layer; a lighting device, a display device and a white electroluminescent device, each of which is provided with this organic electroluminescent element; and a method for manufacturing an organic electroluminescent element. A coating liquid for forming a light emitting layer according to the present invention is used for the purpose of forming a light emitting layer, which is one of one or more organic layers held between a positive electrode and a negative electrode, and this coating liquid for forming a light emitting layer is characterized by containing a thermally activated delayed fluorescent compound.

Abstract: A thin-film transistor array includes thin-film transistors each including an insulating substrate which is formed with a gate electrode, a gate wiring, a capacitor electrode and a capacitor wiring. A source electrode and a drain electrode having a gap therebetween and including a semiconductor pattern are formed, in a region overlapping with the gate electrode on the substrate via a gate insulator, with the semiconductor pattern being covered with a protective layer. Two such TFTs are independently formed for each pixel. In each pixel, two source electrodes are separately connected to two respective source wirings, and two drain electrodes are connected to an electrode of the pixel via individual drain-connecting electrodes. The array includes source-connecting electrodes each connecting between the source electrodes of the two TFTs formed for each pixel. The same drive waveform is applied to the two source wirings.

Abstract: A compound comprising a ligand LA selected from: as well as, devices and formulations containing the compound are disclosed. In the compounds, independently X1-X6 are CH or N; Y1-Y12 are independently selected from CH, N, and C-APR1?R1?; when present, exactly one of Y1 through Y12 is C-APR1?R1? in LA8; A is selected from a single bond, —CRARB—, —NRA—, —O—, —S— and —SiRARB—; and R, R1?, R1?, R2, R3, RA, and RB are each independently a substituent selected from hydrogen, deuterium, alkyl, cycloalkyl, aryl, and combinations thereof. The P-atom of the ligand LA is bonded to a metal M having an atomic weight of at least 40.

Abstract: A method of fabricating a light emitting diode includes providing a substrate, and forming successively an N-type layer, an active layer, an electronic blocking layer, and a P-type layer over the substrate. The P-type layer includes a Mg-doped GaN material layer having a Mg impurity concentration of about 2×1019-2×1020 cm?3; and has a thickness of less than or equal to about 250 ?, and has a surface density of V-type defects of less than or equal to about 5×106 cm?2. Through these optimized growth conditions for the P-type layer, the light absorption of the P-type layer can be reduced, the electric leakage due to the relatively large density of V-type defects on the surface can be reduced, and the anti-static capacity of the light emitting diode fabricated thereby can be improved.

Abstract: Many of the physical properties of a silicon semiconductor have already been understood, whereas many of the physical properties of an oxide semiconductor have been still unclear. In particular, an adverse effect of an impurity on an oxide semiconductor has been still unclear. In view of the above, a structure is disclosed in which an impurity that influences electrical characteristics of a semiconductor device including an oxide semiconductor layer is prevented or is eliminated. A semiconductor device which includes a gate electrode, an oxide semiconductor layer, and a gate insulating layer provided between the gate electrode and the oxide semiconductor layer and in which the nitrogen concentration in the oxide semiconductor layer is 1×1020 atoms/cm3 or less is provided.

Abstract: The disclosure provides a double-side display, a display module and a TFT array substrate thereof, the TFT substrate includes two graphene display units disposed opposite and a reflective layer disposed between the two graphene display units. Compared with a conventional technique, according to the double-side display, the display module and the TFT array substrate thereof, the graphene display units are disposed on the two sides of the reflective layer respectively to prevent influence between light of the two sides of the reflective layer, brightness of two display units is improved due to reflective light from the reflective layer; the structure of the double-side display is simpler, and the volume is reduced significantly, which are benefit for thinning and lightening the double-side display.

Abstract: A memory device includes at least one memory cell which contains a resistive memory element having a conductive metal oxide located between a first electrode and a second electrode. The conductive metal oxide has a concentration of free electrons in thermodynamic equilibrium in a range from 1.0×1020/cm3 to 1.0×1021/cm3. A method of operating the memory device includes redistributing electron density to set and reset the device. An oxide barrier layer may be located between the conductive metal oxide and the second electrode.

Abstract: A semiconductor device includes a substrate and a p-doped layer including a doped III-V material on the substrate. A dielectric interlayer is formed on the p-doped layer. An n-type layer is formed on the dielectric interlayer, the n-type layer including a high band gap II-VI material to form an electronic device.

Abstract: A device includes: a substrate; and a functional element mounted, the functional element including electrodes. The substrate includes a support substrate, and includes a first seed metal, a second seed metal, and a resin component on the support substrate, the first seed metal being disposed in a section opposed to part or all of a first electrode among the electrodes, and being connected to the first electrode by plating, the second seed metal being disposed in a section opposed to part or all of a second electrode among the electrodes, and being connected to the second electrode by plating, and the resin component being disposed in a layer between the functional element and the support substrate, and fixing the functional element to the support substrate, and being, provided avoiding a neighborhood of an end of the functional element among, opposed side sections of the first and second seed metals.

Abstract: A compound comprising a ligand LA of Formula I: as well as, devices and formulations containing the compound of Formula 1 are disclosed. In the compounds, having a ligand La of Formula I: wherein R1 represents mono, or di-substitution, or no substitution; wherein R2 represents mono, di, tri, or tetra-substitution, or no substitution; wherein R is selected from hydrogen, deuterium, alkyl, cycloalkyl, and combinations thereof; wherein R1 and R2 are each independently selected from hydrogen, deuterium, alkyl, cycloalkyl, aryl, and combinations thereof; wherein any adjacent substituents of R2 are optionally joined to form a fused ring; wherein the ligand LA is coordinated to a metal M; and wherein the ligand LA is optionally linked with other ligands to comprise a tridentate, tetradentate, pentadentate or hexadentate ligand.

Abstract: A semiconductor device includes a pixel portion having a first thin film transistor and a driver circuit having a second thin film transistor. Each of the first thin film transistor and the second thin film transistor includes a gate electrode layer, a gate insulating layer, a semiconductor layer, a source electrode layer, and a drain electrode layer. Each of the layers of the first thin film transistor has a light-transmitting property. Materials of the gate electrode layer, the source electrode layer and the drain electrode layer of the first thin film transistor are different from those of the second transistor, and each of the resistances of the second thin film transistor is lower than that of the first thin film transistor.

Abstract: A method of manufacturing ZnO-containing semiconductor structure includes steps of: (a) forming a subsidiary lamination, including alternately laminating at least two periods of active oxygen layers and ZnO-containing semiconductor layers doped with at least one species of group 3B element; (b) alternately laminating said subsidiary lamination and AgO layer, sandwiching an active oxygen layer, to form lamination structure; and (c) carrying out annealing in atmosphere in which active oxygen exists and pressure is below 10?2 Pa, intermittently irradiating oxygen radical beam on a surface of said lamination structure, forming a p-type ZnO-containing semiconductor structure co-doped with said group 3B element and Ag.

Abstract: An object is to provide a semiconductor device including an oxide semiconductor, which has stable electric characteristics and high reliability. In a transistor including an oxide semiconductor film, the oxide semiconductor film is subjected to dehydration or dehydrogenation performed by heat treatment. In addition, as a gate insulating film in contact with the oxide semiconductor film, an insulating film containing oxygen, preferably, a gate insulating film including a region containing oxygen with a higher proportion than the stoichiometric composition is used. Thus, oxygen is supplied from the gate insulating film to the oxide semiconductor film. Further, a metal oxide film is used as part of the gate insulating film, whereby reincorporation of an impurity such as hydrogen or water into the oxide semiconductor is suppressed.

Abstract: A semiconductor optical device has a multilayer structure 30 including a first compound semiconductor layer 31, an active layer 33, and a second compound semiconductor layer 32. A second electrode 42 is formed on the second compound semiconductor layer 32 through a contact layer 34. The contact layer 34 has a thickness of four or less atomic layers. When an interface between the contact layer 34 and the second compound semiconductor layer 32 is an xy-plane, a lattice constant along an x-axis of crystals constituting an interface layer 32A which is a part of the second compound semiconductor layer in contact with the contact layer 34 is x2, a lattice constant along a z-axis is z2, a length along an x-axis in one unit of crystals constituting the contact layer 34 is xc?, and a length along the z-axis is zc?, (zc?/xc?)>(z2/x2) is satisfied.