Opnext Japan, Inc.

Lumentum Japan, Inc.

Oclaro Japan, Inc.

Kaoru Okamoto

Atsushi Nakamura

Ryu Washino

Shigenori Hayakawa

Tetsuya Nishida

Shigetaka Hamada

Ryosuke Nakajima

Kazuhiro Komatsu

Masatoshi Arasawa

Kouji Nakahara

Yasushi Sakuma

Takeshi Kitatani

Daisuke Nakai

Shunya Yamauchi

Susumu Sorimachi

Seiji Sumi

A semiconductor optical amplifier integrated laser includes a semiconductor laser oscillator portion that oscillates laser light having a wavelength included in a gain band and a semiconductor optical amplifier portion that amplifies laser light output from the semiconductor laser oscillator portion. The semiconductor laser oscillator portion and the semiconductor optical amplifier portion have one common p-i-n structure, the common p-i-n structure includes an active layer, a cladding layer provided apart from the active layer, and a common functional layer formed in the cladding layer, and the common functional layer includes a first portion that reflects light having a wavelength within the gain band in the semiconductor laser oscillator portion and a second portion that transmits light having a wavelength within the gain band in the semiconductor optical amplifier portion.

Semiconductor optical amplifier integrated laser

A electro-absorption optical modulator includes a multiple quantum well composed of a plurality of layers including a plurality of quantum well layers and a plurality of barrier layers that are alternately stacked, the plurality of quantum well layers and the plurality of barrier layers including an acceptor and a donor; a p-type semiconductor layer in contact with an uppermost layer of the plurality of layers; and an n-type semiconductor layer in contact with a lowermost layer of the plurality of layers, the multiple quantum well being 10% or more and 150% or less of the p-type semiconductor layer in a p-type carrier concentration, and in the multiple quantum well, an effective carrier concentration which corresponds to a difference between the p-type carrier concentration and an n-type carrier concentration is &#xb1;10% or less of the p-type carrier concentration of the multiple quantum well.

Electro-absorption optical modulator and manufacturing method thereof

An optical semiconductor device includes an InP substrate; an active layer disposed above the InP substrate; a n-type semiconductor layer disposed below the active layer; and a p-type clad layer disposed above the active layer, wherein the p-type clad layer includes one or more p-type InAlP layers, the Al composition x of each of the one or more p-type InAlP layers is equal to or greater than a value corresponding to the doping concentration of a p-type dopant, and the absolute value of the average strain amount of the whole of the p-type clad layer is equal to or less than the absolute value of a critical strain amount obtained by Matthews' relational expression, using the entire layer thickness of the whole of the p-type clad layer as a critical layer thickness.

Optical semiconductor device, optical subassembly, and optical module

Provided is a semiconductor optical device, which has a buried heterostructure structure and is formed in a structure capable of reducing a parasitic capacitance to further improve characteristics thereof, and also provided are an optical transmitter module, an optical transceiver module, and an optical transmission equipment. The semiconductor optical device includes a modulator portion for modulating light input along an emitting direction and radiating the modulated light, the modulator portion including: a mesa-stripe structure, which includes an active layer and extends in the emitting direction; and a buried layer provided adjacent to each side of the mesa-stripe structure, in which a distance between a lower surface of the buried layer and a lower surface of the active layer is 20% or more of a distance between the lower surface and an upper surface of the buried layer.

Semiconductor optical device, optical transmitter module, optical transceiver module, and optical transmission equipment

A method of manufacturing semiconductor laser device capable of reducing &#x3ba;L, with manufacturing restrictions satisfied, is provided. In a distributed-feedback or distributed-reflective semiconductor laser device, immediately before burying regrowth of a diffraction grating, halogen-based gas is introduced to a reactor, and etching is performed on the diffraction grating so that each side wall has at least two or more crystal faces and a ratio of length of an upper side in a waveguide direction to a bottom side parallel to a (100) surface is 0 to 0.3. And, a reactive product formed on side surfaces of the diffraction grating and in trench portions between stripes of the diffraction grating at an increase of temperature for regrowth is removed. Therefore, the diffraction grating with reduced height and a sine wave shape is obtained, thereby &#x3ba;L of the device is reduced. Thus, an oscillation threshold and optical output efficiency can be improved.

Semiconductor laser device and method of manufacturing the same

In an optical semiconductor device that emits or receives light substantially perpendicularly to or in parallel to an active surface formed on a semiconductor substrate, the optical semiconductor device, an electrode that is formed on the active surface side and connected to the active surface is stepped or tapered at an end of the electrode. The electrode of the optical semiconductor device is formed of three layers including an adhesive layer, a diffusion prevention layer, and an Au layer, and the stepped configuration or the taped configuration is formed by a difference of the thickness of the Au layer or the thickness of the adhesive layer/diffusion prevention layer/Au layer.

Method for manufacturing optical semiconductor device

In a mesa type PIN-PD formed using a heavily doped semiconductor material, a high frequency response is degraded as slow carriers occur in a heavily doped layer when light incident into a light receiving section transmits through an absorbing layer and reaches the heavily doped layer on a side near the substrate. In a p-i-n multilayer structure, a portion corresponding to a light receiving section of a heavily doped layer on a side near a substrate is previously made thinner than the periphery of the light receiving section by an etching or selective growth technique, over which an absorbing layer and another heavily doped layer are grown to form the light receiving section of mesa structure. This makes it possible to form a good ohmic contact and to realize a PIN-PD with excellent high frequency response characteristics.

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Yokohama, Japan

Kaoru Okamoto