The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 07, 2015
Filed:
Jun. 08, 2010
Junichi Fujikata, Tokyo, JP;
Jun Ushida, Tokyo, JP;
Akio Toda, Tokyo, JP;
Motofumi Saitoh, Tokyo, JP;
Junichi Fujikata, Tokyo, JP;
Jun Ushida, Tokyo, JP;
Akio Toda, Tokyo, JP;
Motofumi Saitoh, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
A downsized, low-power electro-optical modulator that achieves reducing both of the additional resistance in the modulation portion and the optical loss each caused by electrodes at the same time is provided. The electro-optical modulator includes a rib waveguide formed by stacking a second semiconductor layerhaving a different conductivity type from a first semiconductor layeron the first semiconductor layervia a dielectric film, and the semiconductor layersandare connectable to an external terminal via highly-doped portionsand, respectively. In a region in the vicinity of contact surfaces of the semiconductor layersandwith the dielectric film, a free carrier is accumulated, removed, or inverted by an electrical signal from the external terminal, and whereby a concentration of the free carrier in an electric field region of an optical signal is modulated, so that a phase of the optical signal can be modulated. At least one of the semiconductor layersandis wider than the stacked portion. At least one of the highly-doped portionsandis formed outside the stacked portion.