New double-heterostructure indium-tin oxide/InGaAsP/AlGaAs surface light-emitting diodes at 650-nm range

Abstract
New double‐heterostructure indium‐tin oxide/InGaAsP/AlGaAs surface light‐emitting diodes have been fabricated by liquid‐phase epitaxy and rf sputtering methods. In this structure, indium‐tin oxide acts as both an n‐type cladding layer and a transparent conductor. Peak wavelength and full width at half maximum of the surface emitting spectrum were 653 and 17 nm, respectively. An output power of 1 mW was achieved at a current level of 66 mA, corresponding to a current density of 22 A/cm2 under pulsed operation for the diode with a 400 μm×450 μm emitting area. The optical emission was distributed over the entire emitting area.