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:
Aug. 17, 1993
Filed:
Nov. 13, 1991
Applicant:
Inventors:
Susumu Asada, Tokyo, JP;
Kaori Kurihara, Tokyo, JP;
Assignee:
NEC Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01S / ;
U.S. Cl.
CPC ...
372 45 ; 257 98 ; 359584 ; 372 96 ; 372 99 ;
Abstract
A semiconductor multilayer reflector (Distributed Bragg Reflector) includes a plurality of first quarter-wavelength layers each having a high refractive index, a plurality of second quarter-wavelength layers each having a low refractive index, and high concentration impurity doping regions. The first and second layers are piled up alternately, and each of the doping regions is formed at a heterointerface between the first and second layer. In this structure, the width and the height of the potential barrier at the heterointerface becomes small, so that tunnel current flowing through the multilayer reflector is increased.