Nippon Telegraph and Telephone Corporation

Nec Corporation

Tai Tsuchizawa

Takuma Aihara

Shinji Matsuo

Tatsuro Hiraki

Takaaki Kakitsuka

Junichi Fujikata

Keishi Ohashi

Koji Yamada

Hirofumi Morita

Jun Ushida

Daisuke Okamoto

Kenichi Nishi

Shingo Uchiyama

Tetsufumi Shoji

Emi Tamechika

Toshifumi Watanabe

Tatsurou Hiraki

Jyun-ichi Takahashi

Seiichi Itabashi

A wavelength tunable laser formed on a substrate made of single-crystal silicon is provided. The wavelength tunable laser includes a light emitting portion made of a III-V compound semiconductor, and external resonators provided with an optical filter. Cores included in the external resonators are made of one of SiN, SiON, and SiO(n is smaller than 2).

Semiconductor optical element

A silicon nitride core is formed on a silicon core via a first silicon oxide layer, and a germanium pattern caused to selectively grow in an opening penetrating through a second silicon oxide layer formed on the silicon nitride core and the first silicon oxide layer is formed on a lower silicon pattern formed to be continuous with the silicon core, thereby constituting a Ge photodiode.

Optical module and method for manufacturing the same

A core, constituted by an amorphous undoped semiconductor (i type), which is formed on a lower clad layer, and a p-type layer and an n-type layer which are disposed on the lower clad layer with the core interposed therebetween and are formed in contact with the core are provided. The core is formed to be thicker than the p-type layer and the n-type layer. The p-type layer and the n-type layer are constituted by single crystal silicon.

Optical modulator

An embodiment semiconductor optical device includes an optical waveguide including a core, and an active layer extending in the waveguide direction of the optical waveguide for a predetermined distance and arranged in a state in which the active layer can be optically coupled to the core. The core and the active layer are arranged in contact with each other. The core is formed of a material with a refractive index of about 1.5 to 2.2, such as SiN, for example. In addition, the core is formed to a thickness at which a higher-order mode appears. The higher-order mode is an Emode, for example.

Included are an optical waveguide including a first cladding layer formed on a substrate; a core formed on the first cladding layer; and a second cladding layer formed on the first cladding layer so as to cover the core. At least one of the first cladding layer and the second cladding layer is composed of a cladding material of silicon oxide containing deuterium atoms. The number of hydrogen atoms contained in the cladding material is smaller than the number of the deuterium atoms contained in the cladding material.

Optical integrated device and production method therefor

In a waveguide path coupling-type photodiode, a semiconductor light absorbing layer and an optical waveguide path core are adjacently arranged. An electrode formed of at least one layer is installed in a boundary part of the semiconductor light absorbing layer and the optical waveguide path core. The electrodes are arranged at an interval of (1/100)&#x3bb; to &#x3bb; [&#x3bb;: wavelength of light transmitted through optical waveguide path core]. At least a part of the electrodes is embedded in the semiconductor light absorbing layer. Embedding depth from a surface of the semiconductor light absorbing layer is a value not more than &#x3bb;/(2 ns) [ns: refractive index of semiconductor light absorbing layer]. At least one layer of the electrode is constituted of a material which can surface plasmon-induced.

Waveguide path coupling-type photodiode

An optical module includes an under cladding, a first core, a second core, and an over cladding. The under cladding has a flat shape as a whole. The first core has a quadrangular cross section and is placed on the under cladding. The second core is placed on a terminal end portion of the first core. The over cladding is placed in a region including the terminal end portion of the first core and the second core placed on the terminal end portion of the first core. The under cladding and the first core placed thereon constitute a first optical waveguide. The under cladding, the terminal end portion of the first core placed on the under cladding, the second core placed thereon, and the over cladding placed on and around the second core constitute a mode field size conversion portion. The under cladding, the second core placed on the under cladding, and the over cladding placed on and around the second core constitute a second optical waveguide. The first core is made of silicon. The first and second cores differ in cross-sectional shape. A manufacturing method for the optical module is also disclosed.

Growing community of inventors

Tokyo, Japan

Tai Tsuchizawa