Semiconductor laser
US5274656A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 8, 1992 |
| Grant date | Dec 28, 1993 |
| Priority date | — |
| Expiry date | Jun 8, 2012 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01S5/3215
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A p-clad layer constituting the semiconductor laser device according to this invention includes an inner clad area near an active layer, and an outer clad area remote from the active layer. The outer clad area has a narrower bandgap than that of the inner clad area, the thickness and the composition of the inner clad area are so set that beams do not substantially exude from the active layer to the outer clad area. A multi-quantum barrier structure can be provided between the active layer and the p-clad layer. At least one of barrier layers of the multi-quantum barrier structure is formed of a material which applies tensile stress thereto, and at least one well layer, provided between one of the barrier layers and its adjacent one, is formed of a material which applies contraction stress thereto, whereby an average lattice constant of the multi-quantum barrier agrees with that of the substrate. The material in the barrier layers allows the bandgap thereof to be sufficiently wide. Consequently even in comparatively high-temperature environments, carriers, especially electrons, can be prevented from overflowing from the active layer to the clad layers, and no deterioration of the cha…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.