Kabushiki Kaisha Toshiba

Tokyo Shibaura Denki Kabushiki Kaisha

Nawoto Motegi

Masaki Okajima

Hideto Furuyama

Yuzo Hirayama

Nobuo Suzuki

Masaru Nakamura

Motoyasu Morinaga

Hajime Okuda

Masayuki Ishikawa

Genichi Hatakoshi

Yukio Watanabe

Hiroshi Mitsuhashi

Naohiro Shimada

Atsushi Kamata

Tsutomu Uemoto

Yutaka Uematsu

Hiroko Nagasaka

Yuhei Muro

Yuhei Muto

An optical semiconductor device is provided with a p-type ZnSe semiconductor layer. Si, Cl and O atoms are added, as dopants, to the ZnSe semiconductor layer. Associations of the Si, Cl and O atoms are formed to define a shallow acceptor level in the semiconductor layer. Each of the associations comprises one Si atom, one Cl atom and one O atom by which the lattice points of Se are displaced between those crystal lattice points in the semiconductor layer which are adjacent to one another.

P-type II-VI compound semiconductor doped

A visible-light wavelength continuous oscillation laser is disclosed which has an N type GaAs substrate, an N type GaAlAs cladding layer formed on the substrate, and a non-doped GaAlAs active layer formed on the cladding layer. The laser further includes two N type GaAlAs layers, a P type GaAlAs optical guide layer, a P type cladding layer consisting of upper and lower portions, and a ridge section. The N type GaAlAs layers contact both sides of the ridge section. The optical guide layer is sandwiched between the upper and lower portions of the P type cladding layer, is located within the ridge section, and has a refractive index greater than that of the P type cladding layer. The distance between the active layer and the optical guide layer does not depend on the condition in which etching is performed to form the ridge section, but depends basically on the time required to grow crystal.

Transverse-mode oscillation semiconductor laser device

A semiconductor laser device comprises a semiconductor mesa portion formed above semiconductor substrate by a predetermined interval, an active region, formed between the mesa portion and semiconductor substrate and consisting of a semiconductor having a forbidden band width smaller than those of the mesa portion and semiconductor substrate, for contributing to light emission, a pair of buried portions formed at both sides in a widthwise direction of and in contact with the active region and consisting of a semiconductor having a forbidden band width larger than that of the active region, a total width of the buried portions and the active region being smaller than that of the mesa portion, thereby forming a gap at a side of each of the buried portions between the mesa portion and semiconductor substrate to electrically insulate the mesa portion and semiconductor substrate, and supporting portions formed integrally with the mesa portion so as to support the mesa portion with respect to the substrate in association with the active region and the buried portions.

Semiconductor laser device

A hetero junction type semiconductor laser device is provided wherein a hetero layer is formed on a clad layer leaving a stripe shape portion. The clad layer is formed on an active layer over a substrate. At least two coating layers of the same conductivity type as the clad layer are formed on the hetero layer so as to have a current confining effect and a built-in waveguide effect. The refractive index of the coating layers which is nearer to the active layer is greater than the refractive index of the clad layer and the refractive index of the other coating layer is smaller than the refractive index of the coating layer which is nearer to the active layer. Using this construction, a low lasing threshold current is achieved.

Semiconductor laser device having current confining and built-in

A rib-waveguide semiconductor laser device comprising a first clad layer, an active layer, an optical rib-waveguide layer and a second clad layer, each composed of III-V semiconductor material, and sequentially formed on an insulating substrate or a III-V semiconductor substrate, wherein the rib-waveguide layer contains aluminum. A method for manufacturing the semiconductor laser device as defined above wherein the second clad layer is formed by metal-organic material chemical vapor deposition or molecular beam epitaxy.

Semiconductor laser device and method for manufacturing the same

A compound semiconductor is dry-etched by introducing a plasma-generating gas comprising boron trichloride and chlorine into a plasma generation region which is defined between a cathode for supporting a workpiece comprising a compound semiconductor and an anode opposite thereto. High-frequency electric power is applied between the cathode and the anode, thereby generating a plasma from the introduced plasma-generating gas. The compound semiconductor is etched with the thus formed plasma.

Dry etching method of compound semiconductor

A double heterojunction structure type semiconductor laser device comprising an active layer of GaAlAs in which the laser is excited, n-Ga.sub.0.45 Al.sub.0.55 As clad layer and a p-Ga.sub.0.45 Al.sub.0.55 As clad layer sandwiching the active layer between them in order to confine the laser light in the active layer, an n-GaAs current blocking layer disposed between the active layer and the p-Ga.sub.0.45 Al.sub.0.55 As clad layer in order to confine current, and a p-Ga.sub.0.63 Al.sub.0.37 As optical waveguide layer disposed between the active layer and the current confinement layer. The refractive index of the optical waveguide layer is greater than that of the both of the clad layers.

Semiconductor laser device having a double heterojunction structure

Growing community of inventors

Kanagawa, Japan

Nawoto Motegi