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:
Mar. 21, 1989
Filed:
Jun. 26, 1986
Shigeo Sugou, Tokyo, JP;
Tomoo Yanase, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
An improved buried heterostructure semiconductor laser comprises high resistive burying layers positioned at both sides of an active region so that the high speed modulation is possible to be performed and the higher quantum efficiency is obtained for the reason why the capacitance and leakage current are diminished. A further improved buried heterostructure semiconductor laser comprises spacer layers between an active region and respective high resistive burying layers so that the reliability is maintained to be high for the reason why the diffusion of an impurity is avoided from the respective high resistive burying layers to the active region. Further, an improved process for the fabrication of a buried heterostructure semiconductor laser comprises steps of a buried heterostructure semiconductor laser comprises steps of forming mesa stripe including an active region on the upper portion of a double heterostructure and forming high resistive burying layers to be positioned at both sides of the active region.