The electroluminescence (EL) uniformity of AlGaN-based deep UV laser diodes on AlN substrate was analyzed by using the EL imaging technique. Although nonuniform EL patterns were observed, the uniformity was improved by changing the position of the p-electrode. The threshold current density was also reduced by suppressing the inhomogeneity of the EL. Cathodoluminescence analysis revealed that the cause of the non-uniformity is the degradation of the active layer and the nonuniformity emission formed by rapid thermal annealing at high temperature after mesa structure formation.

中文翻译：

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热处理工艺对AlN衬底上AlGaN基深紫外激光二极管阈值电流密度的影响

利用EL成像技术分析了AlN衬底上AlGaN基深紫外激光二极管的电致发光(EL)均匀性。虽然观察到不均匀的 EL 图案，但通过改变 p 电极的位置提高了均匀性。通过抑制 EL 的不均匀性也降低了阈值电流密度。阴极发光分析表明，不均匀的原因是有源层的退化和台面结构形成后在高温下快速热退火形成的不均匀发射。