Semiconductor laser structure and manufacture

US4278949A · kind A · utility

Assignee

• Licentia Patent-Verwaltungs-GmbH · DE

Inventors

• Peter Marschall · Heilbronn, DE
• Ewald Schlosser · Senden, DE
• Claus Wolk · Erbach, DE

Key dates

• Filing date: May 21, 1979
• Grant date: Jul 14, 1981
• Expiry date: May 21, 1999

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01S5/3202
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

In a semiconductor laser composed of a sequence of layers forming a heterostructure diode and including a substantially homogeneously doped layer defining a laser active zone having a laser radiation exit face perpendicular to the layers, the current flowing in the forward direction of the diode is constricted to a narrow, strip-shaped region in the laser active zone by providing a monocrystalline layer located in the layer sequence to be spaced from the active zone by at least one intervening, doped semiconductor layer, providing the surface of the monocrystalline layer directed away from the active zone with a trough-shaped recess extending essentially perpendicularly to said radiation exit face, and diffusing, via the surface provided with the recess, and toward the active zone, doping material which produces a doped region of same conductivity type as the intervening, doped layer, the doped region being delimited by a diffusion front substantially parallel, and corresponding in contour, to the surface provided with said recess, and located to provide a localized semiconductor region of a single conductivity type in the area below the recess and between the recess and said activ…