Abstract: An optical transmitter according to one embodiment includes: a plurality of light emitting elements; a plurality of light receiving elements that monitor output lights from the respective plurality of light emitting elements; a housing that mounts the plurality of light emitting elements and the plurality of light receiving elements; and a wiring board which is mounted on the housing and which is provided with a first region having a pad electrically connected to the light emitting element and a second region disposed at a position lower than the first region and having a pad electrically connected to the light receiving element.

Abstract: A semiconductor device includes a semiconductor chip including a substrate, a transistor provided on an upper surface of the substrate and having an input electrode to which a high frequency signal is input, an output electrode from which the high frequency signal is output, and a reference potential electrode to which a reference potential is supplied, and a metal pattern provided on the upper surface of the substrate and electrically connected to the reference potential electrode, a first capacitor including a first lower electrode provided on the metal pattern and electrically connected to the metal pattern, a first dielectric layer provided on the first lower electrode, and a first upper electrode provided on the first dielectric layer, and a first bonding wire electrically connecting the first upper electrode and a first electrode which is any one of the input electrode and the output electrode.

Abstract: An optical semiconductor device includes: a mesa that is provided on a surface in a <011> direction of a semiconductor substrate having a (100) plane orientation and being of a first conductivity type, and includes a first cladding layer of the first conductivity type, an active layer, and a second cladding layer of a second conductivity type; a semi-insulating buried layer that buries both sides of the mesa, is provided on the semiconductor substrate, and includes a first region and a second region farther from the mesa than the first region; an insulation film provided on the first and second regions of the buried layer; and an electrode provided on the mesa and the insulation film on the first region; wherein a surface of the first region is at a height equal to or lower than a surface of the mesa, and lowers at farther distances from the mesa.

Abstract: A semiconductor device includes a wiring substrate including an opening formed to penetrate from a first main surface to a second main surface, and configured to include an insulating material, a metal substrate fixed to the wiring substrate to cover the opening from the second main surface side, a semiconductor chip fixed inside the opening on a main surface of the metal substrate, a resin disposed to cover the semiconductor chip from above the first main surface on the main surface, and formed of a material having a thermal expansion coefficient different from that of the wiring substrate, and an adhesive containing a metal paste disposed between a side surface of the wiring substrate and the main surface, and the resin, in which the adhesive is disposed on the main surface so that a thickness gradually increases from a center side of the opening to the side surface.

Abstract: An optical apparatus includes a light emitting apparatus and a host apparatus. The light emitting apparatus includes a housing extending in a first direction, a light emitting device mounted in the housing, an optical connector including a first optical connection part provided at one end of the housing, and an electrical connector including a first electrical connection part provided at one end of the housing and receiving a voltage to drive the light emitting device. The host apparatus includes a host optical connector including a second optical connection part which faces the first optical connection part and is optically coupled thereto, a host electrical connector including a second electrical connection part facing the first electrical connection part and being electrically connected to the first electrical connection part, and a host board mounting the host optical connector and the host electrical connector thereon.

Abstract: A semiconductor device includes a substrate, a semiconductor layer provided on the substrate, a gate electrode, a drain electrode, and a source electrode provided so as to dispose the gate electrode between the drain electrode and the source electrode, wherein via holes are provided in the substrate and the semiconductor layer, the via holes overlap with the source electrode when viewed from a thickness direction of the substrate, penetrate through the semiconductor layer and the substrate, and are arranged in an extending direction of the source electrode, the via holes include a first via hole closest to a first end of the gate electrode to which a signal is inputted, the first via hole is in contact with the source electrode with a first area, and the first area is the smallest of a plurality of areas in which the via holes are in contact with the source electrode.

Abstract: Disclosed is a package for a semiconductor device including a semiconductor die. The package includes a base member, a side wall, first and second conductive films, and first and second conductive leads. The base member has a conductive main surface including a region that mounts the semiconductor die. The side wall surrounds the region and is made of a dielectric. The side wall includes first and second portions. The first and second conductive films are provided on the first and second portions, respectively and are electrically connected to the semiconductor die. The first and second conductive leads are conductively bonded to the first and second conductive films, respectively. At least one of the first and second portions includes a recess in its back surface facing the base member, and the recess defines a gap between the at least one of the first and second portions below the corresponding conductive film and the base member.

Abstract: A semiconductor device includes a silicon carbide substrate, a nitride semiconductor layer provided on a top surface of the silicon carbide substrate, a transistor provided on the nitride semiconductor layer, and an element provided on or above the silicon carbide substrate, wherein the silicon carbide substrate has a hole that is provided between the transistor and the element, the hole is formed by removing at least a part of the silicon carbide substrate from a bottom surface of the silicon carbide substrate and an internal thermal conductivity of the hole is smaller than a thermal conductivity of the silicon carbide substrate.

Abstract: An optical transmitter according to one embodiment includes a housing with an emission end, a light emitting element mounted on a first mounting portion of the housing, and a light receiving element mounted on a second mounting portion of the housing to monitor output light from the light emitting element. The second mounting portion is provided with a carrier, a first resin located on an emission end side of a lower side of the carrier, and a second resin located on a light emitting element side of the lower side of the carrier. A coefficient of thermal expansion of the first resin is smaller than a coefficient of thermal expansion of the second resin.

Abstract: An amplifier includes an amplifier circuit 10 having a characteristic changing in accordance with a thermal history, and a bias circuit 20 that includes an element subjected to a thermal history corresponding to the thermal history of the amplifier circuit, and supplies a bias voltage to the amplifier circuit. The bias voltage changes based on a characteristic of the element that changes in accordance with the thermal history of the element.

Abstract: A high frequency package includes a package having an input terminal and an output terminal. A substrate housed in the package, has a first side, a second side facing the input terminal, and a third side facing the output terminal. The first side extends in a first direction and connects the second side and the third side, and the second side and the third side extend in a second direction intersecting the first direction. A coupling circuit on the substrate is electrically connected to the input terminal and the output terminal to input an input signal from the input terminal disposed at the second side of the substrate and output an output signal to the output terminal disposed at the third side of the substrate. A filter circuit on the substrate is electrically connected to the coupling circuit, an is configured to reduce third-order IMD (Inter Modulation Distortion) included in the output signal.

Abstract: An optical transmitter includes an optical transmission unit, a drive unit, an arithmetic circuit, and a bias supply circuit. The optical transmission unit includes a laser element. The drive unit drives the laser element according to a first transmission signal. The arithmetic circuit generates a second transmission signal. The bias supply circuit superimposes the second transmission signal on a bias current of the laser element. An output of the arithmetic circuit containing the second transmission signal is a digital signal in a rectangular wave form based on a reference clock having a frequency lower than a reference clock frequency of the first transmission signal. The bias supply circuit includes a circuit element for inclining a rising portion and a falling portion of the output of the arithmetic circuit.

Abstract: Disclosed is an optical semiconductor device including a semiconductor laser chip, an insulation substrate, a ground pattern, a mounted pattern, a resistor and an extension ground pattern. The insulation substrate has a surface mounting the semiconductor laser chip thereon. The ground pattern and the mounted pattern are provided on the surface. The mounted pattern has an opposite side opposite to the ground pattern. The resistor is disposed such that a side edge of the resistor separates from an extension region of the opposite side. The extension ground pattern is positioned in the extension region of the opposite side and is electrically connected to the ground pattern. The capacitor is disposed on the mounted pattern.

Abstract: A first optical transceiver includes a transmission signal processor that generates a multi-valued pulse amplitude modulation signal including a fixed bit pattern. The first optical transceiver includes an optical transmitter that transmits the multi-valued pulse amplitude modulation signal as an optical transmission signal. The first optical transceiver includes an optical receiver that receives an optical adjustment signal from a second optical transceiver to reproduce an adjustment signal from the optical adjustment signal. The first optical transceiver includes a first controller that controls the transmission signal processor based on a bit error rate included in the optical adjustment signal to adjust light power at each level of the optical transmission signal.

Abstract: An optical module of the present disclosure includes an optical element, a first optical component that is optically coupled to the optical element, a second optical component that is optically coupled to the first optical component, a receptacle to which an optical fiber that transmits the incident light to the second optical component is connected, a terminal unit that electrically outputs an output signal of the optical element to the outside, and a package that accommodates the optical element, the first optical component, and the second optical component and is provided with the receptacle on a first surface and the terminal unit on a second surface facing the first surface, wherein the wiring extends from the first surface side to the second surface side and electrically connects the second optical component and the terminal unit.

Abstract: A semiconductor device manufacturing method includes: forming an electrode including an Ni layer and an Au layer successively stacked on a semiconductor layer; forming a Ni oxide film by performing heat treatment to the electrode at a temperature of 350° C. or more to deposit Ni at least at a part of a surface of the Au layer and to oxidize the deposited Ni; and forming an insulating film in contact with the Ni oxide film and containing Si.

Abstract: Various embodiments of the present disclosure relate to transmitter systems, methods, and instructions for signal predistortion. The transmitter system includes an intermodulation distortion (IMD) filter module configured to filter a detected feedback signal (Yin) to generate a targeted filtered signal (Yout), a digital pre-distortion (DPD) coefficient estimation module configured to update signal generation coefficients based on comparing an input signal (Sin) with the targeted filtered signal (Yout), and a distortion compensation processing module configured to generate a pre-distorted signal (Uout) based on the input signal (Sin) using the updated signal generation coefficients.

Abstract: A semiconductor light receiving element includes a first semiconductor layer, a waveguide type photodiode structure, an optical waveguide structure, and a fourth semiconductor layer. The waveguide type photodiode structure is provided on the first semiconductor layer. The waveguide type photodiode structure includes an optical absorption layer, a second semiconductor layer, a multiplication layer, and a third semiconductor layer. The optical waveguide structure is provided on the first semiconductor layer. The optical waveguide structure includes an optical waveguiding core layer and a cladding layer. An end face of the waveguide type photodiode structure faces to an end face of the optical waveguide structure. The fourth semiconductor layer is located between the end face of the waveguide type photodiode structure and the end face of the optical waveguide structure. The fourth semiconductor layer contacts the multiplication layer at the end face of the waveguide type photodiode structure.

Abstract: A capacitor according to an embodiment of the present disclosure includes a substrate, a first electrode disposed on the substrate, a dielectric film disposed on the first electrode, a second electrode disposed on the dielectric film, a third electrode in contact with the second electrode in a first region of at least a portion of a lower surface of the third electrode, and an organic insulator film covering an upper portion of the dielectric film, an upper portion of the second electrode, and the third electrode. In a normal direction normal to an upper surface of the substrate, the organic insulator film is not disposed between the lower surface of the third electrode and the second electrode.

Abstract: A capacitor includes a substrate, a first electrode provided on the substrate, a dielectric film provided on the first electrode, a second electrode provided on the dielectric film and having an outer periphery positioned inside the outer periphery of the first electrode in a plan view viewed from above in a direction normal to an upper surface of the substrate, a third electrode that is in contact with the second electrode in a region inside the second electrode in the plan view, is separated upward from the first electrode and the dielectric film outside the region in the plan view, and has an outer periphery positioned inside the outer periphery of the first electrode and an outer periphery of the dielectric film in the plan view, and a protective film covering the second electrode and the third electrode and being in contact with the second electrode and the third electrode.