Room-Temperature Operation of Injection-Type 1.5 μm Light-Emitting Diodes with Er,O-Codoped GaAs

Abstract

Injection-type 1.5 μm light-emitting diodes (LEDs) with Er,O-codoped GaAs (GaAs:Er,O) have been fabricated by organometallic vapor phase epitaxy (OMVPE). Electroluminescence (EL) spectrum from the LEDs under forward bias at room temperature was dominated by the luminescence due to an Er-2O center, an Er atom located at the Ga sublattice with two adjacent O atoms, indicating that injected carriers contribute effectively to the excitation of the Er-2O center. The current density dependence of EL properties revealed an extremely large excitation cross section (approximately 10⁻¹⁵ cm²) of Er ions by current injection. GaInP/GaAs:Er,O/GaInP double-heterostructure (DH) LEDs have also been fabricated. The saturated EL intensity significantly increased with increasing GaAs:Er,O active-layer thickness.