Effect of QW growth temperature on the optical properties of blue and green InGaN/GaN QW structures

Simon Hammersley,Rachel A Oliver,Suman-Lata Sahonta,Fabien C.-P Massabuau,Phil Dawson,Menno J Kappers,Colin J Humphreys

doi:10.1002/pssc.201610187

Simon Hammersley, Rachel A Oliver + Show 5 more

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https://doi.org/10.1002/pssc.201610187

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Abstract

In this paper we report on the impact that the quantum well growth temperature has on the internal quantum efficiency and carrier recombination dynamics of two sets of InGaN/GaN multiple quantum well samples, designed to emit at 460 and 530 nm, in which the indium content of the quantum wells within each sample set was maintained. Measurements of the internal quantum efficiency of each sample set showed a systematic variation, with quantum wells grown at a higher temperature exhibiting higher internal quantum efficiency and this variation was preserved at all excitation power densities. By investigating the carrier dynamics at both 10 K and 300 K we were able to attribute this change in internal quantum efficiency to a decrease in the non-radiative recombination rate as the QW growth temperature was increased which we attribute to a decrease in incorporation of the point defects. (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Highlights

Light emitting diodes (LEDs) are widely used for high efficiency visible light generation, with InGaN quantum wells (QWs) active regions being utilised when emission in the blue and green regions of the visible spectrum is required
In summary, we have investigated the effect of QW growth temperature on the optical properties of blue and green-emitting QW structures grown at different QW growth temperatures while maintaining the indium composition of the QWs
It was found that at low temperatures (10 K) that modification to the QW growth temperature did not have any significant or systematic effect on the PL emission or the PL decay transients recorded at the PL emission peak

Summary

Introduction

Light emitting diodes (LEDs) are widely used for high efficiency visible light generation, with InGaN quantum wells (QWs) active regions being utilised when emission in the blue and green regions of the visible spectrum is required.

Results

Conclusion