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:
Oct. 04, 2011
Filed:
Oct. 24, 2007
Tadao Ishibashi, Tokyo, JP;
Nobuhiro Kikuchi, Atsugi, JP;
Ken Tsuzuki, Atsugi, JP;
NTT Electronics Corporation, Kanagawa, JP;
Nippon Telegraph and Telephone Corporation, Tokyo, JP;
Abstract
The present invention can provide an npin-type optical modulator that has a high withstand voltage and is easily fabricated. A semiconductor optical amplifier () according to an embodiment of the present invention is an npin-type semiconductor optical modulator in which layers are sequentially stacked, with a cathode layer (-) arranged on the substrate side, including at least a first n-type cladding layer (-), a p-type cladding layer (), a core layer () and a second n-type cladding layer (-). In this semiconductor optical modulator, the p-type cladding layer () is electrically connected to an electrode (-) of the cathode layer. Accordingly, the accumulation of holes in the p-type cladding layer associated with light absorption in the npin-type optical modulator can be absorbed in the electrode on the negative side. This npin-type semiconductor optical modulator can be comparatively easily fabricated using conventional semiconductor manufacturing techniques by adopting a mesa type waveguide structure.