Native oxide top- and bottom-confined narrow stripe p-n AlyGa1−yAs-GaAs-InxGa1−xAs quantum well heterostructure laser

Abstract

A new form of AlyGa1−yAs-GaAs-InxGa1−xAs quantum well heterostructure (QWH) laser that is confined above and below the active region by an insulating low refractive index native oxide is demonstrated. The laser diodes are defined from a mesa edge by the selective lateral oxidation and anisotropic oxidation of high Al composition AlyGa1−yAs layers (y=0.85, 0.87) located above and below the QW and waveguide active region. This structure provides excellent current and optical confinement, resulting in continuous wave threshold currents of ∼8 mA and maximum output powers (uncoated laser) of 35 mW/ facet for a∼2.5 μm aperture.

Design, fabrication, and performance of infrared and visible vertical-cavity surface-emitting lasers

“…2(d)]. Wet oxidation of AlGaAs [84], [85], which was successfully implemented in edge emitters [86]- [88], produces highly effective current apertures in hybrid VCSEL's operating with dielectric DBR's [6], as well as in monolithic VCSEL's operating with semiconductor DBR's [89]. Significant improvements in laser performance have been reported for VCSEL's operating at 980, 850, 780, and 650 nm.…”

Fabrication of Current Confinement Aperture Structure by Transforming a Conductive GaN:Si Epitaxial Layer into an Insulating GaOx Layer

“…6,7 Toward the realization of a similar building block for III-nitride photonic devices, several groups are attempted to oxidize III-nitride layers. In the case of GaN the oxidation processes are limited to less than 100 nm (dry oxidation) and revealed microcracks on thick oxide layers from the surface.…”

Huge birefringence in selectively oxidized GaAs/AlAs optical waveguides

“…The oxidation proceeds laterally into an embedded AlAs layer and preserves the quality of the interfaces. It has been applied to provide current and optical confinement for edge 7 and vertical cavity surface 8 emitting lasers, leading to threshold currents as low as 8.7 A, 9 and also to enhance Bragg mirrors' reflectivity and bandwidth. 10 We propose to use this low index oxide to enhance birefringence in a GaAs/AlAs waveguide in order to obtain phase matching between TE and TM modes.…”