Enhancement in light-emission efficiency of InGaN/GaN multiple quantum well layer by a porous-GaN mirror

Mixed electrolyte of oxalic acid and NaNO3, which can be used to fabricate an InGaN/GaN multiple quantum well (MQW) structure with an embedded porous-GaN distributed Bragg reflector (DBR), is more effective than oxalic acid or NaNO3 solutions. Compared to the as-grown GaN-based film, the etched sample was significantly enhanced and narrowed in the intensity and line-width of photoluminescence (PL), respectively, which are contributable to strain relaxation of MQW layer and light-interference effect induced by forming the embedded porous-DBR mirror. Due to the presence of nanopores in the MQW layer, the mass-transport cause the crystalline quality of the MQW layer to deteriorate significantly during the regrowth of GaN-based light emitting diode (LED). Therefore, the performance enhancement of the PL in the LED with the embedded DBR structure should be contributable to improved external and internal quantum efficiencies.