Deep-ultraviolet Laser Diode Characterization Improvement by Inverted Trapezoidal Hole Blocking Layer

Improving optical confinement and threshold currents has been the main focus of AlGaN-based deep-ultraviolet (DUV) laser diode (LD) optimization. In this paper, an inverted trapezoidal hole blocking layer (HBL) is used to increase the optical confinement factor, laser power, stimulated recombination rate and carrier confinement of the DUV LD. Attributed to reduced hole leakage and better optical confinement methods, the optimized device achieves 14.3% OCF at the peak emission wavelength of 267 nm and boasts a lower threshold current and higher slope efficiency (SE).