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:
Dec. 29, 1987
Filed:
Nov. 26, 1986
Masao Makiuchi, Atsugi, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
A compound semiconductor laser comprises a semi-insulating substrate, a lower clad layer, an MQW active layer, an upper clad layer, and two electrodes on the top surface thereof. The upper clad layer is formed so as to have a property of reducing the diffusion coefficient of impurities, from the lower portion toward the upper portion thereof. Impurity atoms are thermally diffused into the lower clad layer from the top surface thereof to form an N-type region and a P-type region, respectively. The side diffusion fronts of the N- and P-type regions are nearly vertical, and thus a narrow MQW active region is defined by disordered portions of the MQW active layer in the N- and P-type regions. The light and carriers are effectively confined in the narrow active region by using the vertical and transverse double-heterostructures and refractive index differences.