AlGaInN violet laser diodes grown on GaN substrates with low aspect ratio

AlGaInN violet laser diodes grown on GaN substrates have been investigated. Waveguide simulations have been performed and a triple-cladding-layer (TCL) technique has been proposed for achieving a small radiation angle in the perpendicular direction to the junction plane. A TCL-type laser has been fabricated. The threshold current density and the slope efficiency were 2.9 kA/cm 2 and 1.4 W/A, respectively. The radiation angle in the perpendicular direction was as small as 16°. A violet laser diode with a low aspect ratio of 1.6 has been realized.