Investigation into low‐temperature photoluminescence internal quantum efficiency and defect‐recombination in InGaN light‐emitting diodes

This paper is focused on the temperature‐dependence of photoluminescence (PL) internal quantum efficiency (IQE) and defect‐recombination in InGaN light‐emitting diodes. It is found low‐temperature PL‐IQE is remarkably lower than 100% for some samples, suggesting the existence of residual defect‐recombination under low temperature. Theoretical analysis deduces that defect‐recombination cannot be frozen out at low temperature, because it follows T 1/2 temperature‐dependent defect‐capture coefficient without defect‐activation energy. The empirical formulas describing temperature‐dependence of defect‐recombination lifetime and PL‐IQE are correspondingly revised. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)