Threshold reduction of p-type δ-doped InGaAs/GaAs quantum well lasers by using auto-doping of carbon
An InGaAs/GaAs quantum well laser using p-type δ-doping selectively in the barriers has been demonstrated to reduce the threshold current and carrier lifetime. A δ-doping technique is proposed, based on the experimental evidence of high density carbon inclusion during AlAs growth by metal organic chemical vapour deposition (MOCVD). A threshold current density as low as 160 A/cm2, (54 A/cm2/well) has been obtained for three quantum well stripe lasers grown at 1.7 × 1018 cm–3 carbon doping.