Suppression of crack generation in AlGaN/GaN distributed Bragg reflectors grown by MOVPE

► AlGaN/GaN DBR structures were grown by MOVPE for RC-LED applications. ► Crack-free DBR stack centered at 384 nm with a 90% reflectivity was demonstrated. ► Smooth surfaces with atomic steps and terraces with low surface roughness were obtained. ► Coherently strained DBR structure was obtained with a good structural quality. ► TEM analysis revealed a homogeneous GaN and AlGaN layers with flat and abrupt interfaces.