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:
Jul. 30, 2013
Filed:
May. 12, 2010
Kenji Sato, Tokyo, JP;
Tomoaki Kato, Tokyo, JP;
Kenji Sato, Tokyo, JP;
Tomoaki Kato, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
Provided are a semiconductor optical modulator and a semiconductor Mach-Zehnder optical modulator of high efficiency and high reliability. The semiconductor optical modulatorof the present invention includes a substrate; a first n-type cladding layer; a semiconductor optical modulation layer; a p-type cladding layer; a second n-type cladding layer; a passivation film; and an electric field-relaxing layer, wherein the first n-type cladding layer, the semiconductor optical modulation layer, the p-type cladding layer, and the second n-type cladding layerare laminated on the substratein this order to form a waveguide structure, the passivation filmis arranged at the side surfaces of the waveguide structure, the electric field-relaxing layeris interposed between the p-type cladding layerand the second n-type cladding layer, and an impurity concentration of the electric field-relaxing layeris lower than that of the p-type cladding layerand that of the second n-type cladding layer