Mitsubishi Denki Kabushiki Kaisha

Mitsubishi Precision Co., Ltd.

Mitsubishi Denki Kabushiki

Etsuji Omura

Shogo Takahashi

Katsuhiko Goto

Akira Takemoto

Hirofumi Namizaki

Harumi Namba

Kimio Shigihara

Satoshi Arimoto

Ryoichi Hirano

Kenichi Kajiwara

A semiconductor light emitting device includes a semiconductor light emitting element mounted on a package stem via a radiating heatsink block, the light emitting point of the light emitting element being positioned on the central axis of the stem and at or near the center of mass of the heatsink block. Another light emitting device includes a light emitting element mounted on a stem via a heatsink block, the light emitting point of the element being positioned on the central axis of the stem with only a portion of a lower surface of the heatsink block close to the central axis of the stem attached to the stem. The movement of the light emitting point with temperature variations is suppressed. Another light emitting device includes a laser chip element mounted on a package stem via a heatsink block, the laser chip element being mounted on the heatsink block so that the emitted light forms an angle .theta. with a surface of the stem and the position and angle of the emitted light do not vary when the temperature changes.

Semiconductor light emitting device

A superluminescent diode (SLD) includes a substrate, a double heterojunction structure including a first conductivity type first cladding layer, an undoped active layer, and a second conductivity type second cladding layer. A second conductivity type first diffused region having a stripe shape and a length extends from a front facet halfway to the rear facet through which current is injected into the active layer and a second conductivity type second diffused region spaced from the first diffused region extends through the second cladding layer and the active layer and into the first cladding layer between the first diffused region and the rear facet of the device. Even when operating at high light output power, light reflections are reduced so that the SLD operates with hardly any laser oscillation.

Superluminescent diode with stripe shaped doped region

A semiconductor light emitting device includes a vertical aperture produced at a main surface of a semi-insulating or insulating substrate, a transverse aperture provided in the substrate communicating with the vertical aperture, a conducting semiconductor layer buried in the vertical aperture and the transverse aperture, a groove produced by etching the substrate from the surface thereof until reaching the conducting semiconductor layer at a portion of the transverse aperture, and a light emitting element produced in the groove, and the light emitting region of the element being buried in the groove and connected with the buried conducting semiconductor layer. Accordingly, no pn junction exists at the periphery of the light emitting region, and a semiconductor light emitting element of quite low parasitic capacitance is obtained at high yield. A planar structure in which two electrodes are produced at the same plane is obtained, resulting in ease of integration and enhancement of the integration density.

Method of producing a semiconductor light emitting device disposed in an

A semiconductor laser device includes a p type semiconductor substrate, an active layer having a smaller energy band gap than the p type semiconductor substrate and an n type semiconductor layer having a larger energy band gap than the active layer successively formed on the p type semiconductor substrate, a mesa formed by selectively etching the semiconductor substrate, active layer, and n type semiconductor layer, p-n-p layers having larger energy band gaps than the active layer and disposed at both sides of the mesa, a small energy band gap layer having a smaller energy band gap than the p type semiconductor substrate and disposed on the p-n-p layers, and an n type semiconductor layer disposed on the small energy band gap layer and on the n type semiconductor layer. The small energy band gap layers decrease the current flowing through the thyristor structure and are disposed close to the active region but in a different processing step from the formation of the active layer. A waveguide structure in which the active layer is surrounded by semiconductor layers having larger energy band gaps is realized.

Semiconductor laser device

A semiconductor light emitting device includes a vertical aperture produced at a main surface of a semi-insulating or insulating substrate, a transverse aperture provided in the substrate communicating with the vertical aperture, a conducting semiconductor layer buried in the vertical aperture and the transverse aperture, a groove produced by etching the substrate from the surface thereof until reaching the conducting semiconductor layer at a portion of the transverse aperture, and a light emitting element produced in the groove, and the light emitting region of the element being buried in the groove and connected with the buried conducting semiconductor layer. Accordingly, no pn junction exists at the periphery of the light emitting region, and a semiconductor light emitting element of quite low parasitic capacitance is obtained at high yield. A planar structure in which two electrodes are produced at the same plane is obtained, resulting in ease of integration and enhancement in the integration density.

A light-controlled semiconductor light coupler for altering the position of and modulating a signal light in response to the intensity of a control light includes a multiple quantum well structure having an index of refraction that varies in response to the intensity of an incident, essentially monochromatic control light, first and second semiconductor light guide layers contacting and sandwiching the multiple quantum well structure for transmitting a signal light beam variably coupled between the first and second light guide layers in response to the intensity of the control light, and first and second semiconductor cladding layers contacting and sandwiching the first and second light guide layers, respectively.

Light-controlled semiconductor light coupler and modulator

A transverse junction stripe semiconductor laser includes a double heterostructure of a first semiconductor layer of a first conductivity type, a second semiconductor layer of the first conductivity type having a smaller energy band gap than that of the first semiconductor layer, and a third semiconductor layer of the first conductivity type having a smaller energy band gap than that of the second semiconductor layer, and an impurity region of the second conductivity type formed through part of the first, second, and third semiconductor layers, wherein the first, second, and third layers are AlGaInAs.

Semiconductor Laser

A semiconductor light modulator for modulating incident light of a particular wavelength according to the invention includes a plurality of successively disposed, alternating p and n conductivity type semiconductor layers, each layer having substantially the same index of refraction and a thickness approximately equal to one-fourth an integer multiple of the wavelength of light to be modulated divided by the index of refraction of the layer, a p-type region extending through the successively disposed layers, an n-type region extending through the successively disposed layers and spaced from the p-type region, a first electrode disposed on and in electrical contact with the p-type region, and a second electrode disposed on and in electrical contact with the n-type region.

Semiconductor light modulator with PN layers

Semiconductor light emitting device disposed in an insulating substrate

A buried heterojunction semiconductor laser appropriate for integration with other electronic circuitry and method of producing same, in which the width of a central stripe of the active region can be reduced beyond the physical size limitations of the connecting electrode so as to allow the semiconductor laser to oscillate in a stable manner and with low threshold current. The semiconductor laser is provided with a portion of the surface of the upper cladding layer located above the disordered active layer regions electrically connected with the upper cladding layer located above the nondisordered central stripe. As a result, the central stripe electrode can be of a width larger than that of the central stripe itself.

Method of making a semiconductor laser using superlattice disordering

A seminconductor laser device includes a hetero-junction structure disposed in a groove in a semi-insulating semiconductor substrate having a first conductivity type first cladding layer, a quantum well active layer, and a first or second conductivity type or high resistance second cladding layer. First and second conductivity type impurity regions are selectively produced at opposite sides of an active region of the active layer and at adjacent portions of the substrate, penetrating at least the active layer. The regions of the active layer in the impurity regions are disordered. Electrodes are disposed on the substrate at the respective impurity regions.

Semiconductor laser device and a method of producing same

A semiconductor laser includes a semiconductor substrate on which a longitudinal groove is provided in the resonator direction, a first semiconductor layer disposed on a region of the semiconductor substrate where the groove is not provided and forming a rectifying junction therewith, a first cladding layer provided on the semiconductor substrate in the groove, an active layer provided on the first cladding layer in the groove, and a second cladding layer provided directly on the active layer and opposite the first semiconductor layer with an interposed insulating layer, such as a gap void of solid material or a gap and current blocking material having only negligible parasitic capacitance.

Method of making a buried crescent laser with air gap insulator

Semiconductor laser

A method for producing a semiconductor device includes producing a first mask film on a main surface of a compound semiconductor wafer, patterning the first mask film and producing a second mask film so as to cover at least an end portion of the first mask film, diffusing impurities into the compound semiconductor wafer under gaseous pressure of atoms, which atoms occur in the compound of the semiconductor wafer, thereby to produce a first conductivity type first diffusion region, thermally diffusing impurities into the wafer under gaseous pressure of atoms, which atoms occur in the compound of the semiconductor wafer, thereby to produce a second conductivity type region. Accordingly, the end of the first mask film can be recognized accurately and used as a reference line for pattern alignment in photolithograph. Thus, diffusions of p type and n type impurities can be conducted at a high positional precision, and an outstanding performance semiconductor device can be obtained.

Growing community of inventors

Itami, Japan

Etsuji Omura