Mitsubishi Denki Kabushiki Kaisha

Toshio Sogo

Yutaka Mihashi

Kenichi Yamanaka

Yasunori Miyazaki

Josuke Nakata

Hisao Kumabe

Saburo Takamiya

An optical semiconductor module includes a substrate including a first plate member having strip lines for high-frequency signal transmission, located on a surface of the substrate and a second plate member including a feeding line on a surface, the first plate member having a loss angle at high frequencies smaller than that of the second plate member, and the second plate member including a material with a higher heat conductivity than that of the first plate member. The optical semiconductor module includes an integrated semiconductor laser and modulator including a modulator region having surface electrodes on a surface, and a laser region having a surface electrode on a surface, with an optical axis extending along the optical axis of the modulator region. The integrated semiconductor laser and modulator are located on the substrate such that the surface electrodes of the modulator region are bonded to the strip lines and the surface electrode of the laser region is bonded to the feeding line.

Optical semiconductor module

A semiconductor laser is provided with an active layer which is bent at an angle at both ends of the resonator so that both ends of the waveguide path are formed by semiconductor cladding layers. The structure is effective in increasing the obtainable optical density while decreasing absorption at the waveguide ends.

Transverse junction stripe laser with steps at the end faces

A thermo-sensitive semiconductor element having a four-layer pnpn structure. A defect layer is formed at the junction of the p base layer and the n base layer by implantation of argon ions to provide a semiconductor element having a desired thermo-sensitive characteristic. The element is subjected to heat treatment such as annealing at temperatures in a range of from 400.degree. C. to 900.degree. C. in a nitrogen atmosphere after the argon ion implantation so that the leakage current into the element having the defect layer is controlled.

Thermo-sensitive switching element manufacturing method

A planar pnpn thyristor structure is prepared to include an SiO.sub.2 film with a thickness of about 10,000A wholly disposed on its main face to which pn junctions are exposed. That portion of the SiO.sub.2 film underlaid with an exposed edge of a collector junction and its adjacent portion are replaced by another SiO.sub.2 film about 1,000A thick. Then argon ions Ar.sup.+ with an implantation energy of 200 KeV are implanted into the thyristor structure through both films to permit a low lifetime region including a large number of lattice defects to be formed only in its main face portion overlaid with the thin SiO.sub.2 film resulting in a semiconductor thermally sensitive switching element effecting the switchover at a sufficiently low temperature.

Growing community of inventors

Itami, Japan

Toshio Sogo