AIIIBV heterostructure simulation and investigation

•Optimum active area structure for increasing quantum efficiency was detected.•In central quantum wells maximum recombination rate occurs, edge – are quasibuffers.•Impurity, defects and Indium atoms influence on efficiency droop was investigated. The optimum of AlGaInN heterostructure was achieved based on computer simulation. The four quantum well structure leads to efficiency increase. The model explaining LED efficiency droop was proposed and proved by AFM investigation. New method for investigation of semiconductor characteristics changes due to external (temperature, current) and internal (different doping, material atoms concentration) influence factors was developed.