The Regularity of the Decrease in the Quantum Yield of Quantum-Wells LEDs at the Long-Term Current Flow from the ABC Model Position

Abstract

The works on degradation of light emitting diodes (LEDs) with quantum wells (QW) were analysed. The calculation model of the relation between LED luminous flux and duration of LED current flow and current density was proposed. It allows us to forecast service life of such radiators with the pre-set electric modes and temperature. It is demonstrated that: – Reduction of quantum yield of LED with QW based on high-bandgap semiconductors with longterm flow of forward current occurs due to generation of point defects in the QW areas; – The dot defects occur as a result of interaction between hot electrons and semiconductor atoms caused by subthreshold displacement out of the lattice dots; – The dot defects create non-radiative recombination centres with particular concentration in the energy gap of a semiconductor, as a result of which intensities of recombination flows in QWs and in barriers between QWs redistribute towards the non-radiative component of the ABC model.