Effects of growth temperature on nitrogen incorporation into InGaPN epilayer and its optical properties

The effect of growth temperature on the nitrogen concentration and optical properties of the InGaP(N) epilayer was investigated. The nitrogen concentration of InGaPN is dependent on the growth temperature (450–490 °C), whereas the indium concentration is independent of the growth temperature. Nitrogen concentration decreased the photoluminescence (PL) intensity and increased the full width at half maximum of the PL peak. Raman analysis revealed that the preferred atomic configuration of InGaPN consisted of Ga–N and In–P bonds, which induced higher local strains during growth. The degradation of PL efficiency was related to this bonding configuration. Nitrogen concentration reduced the coupling constant of electron–phonon interaction, thus, reducing the temperature dependence of the PL peak shift. The reduced PL quenching around room temperature was attributed to the decrease of band discontinuity at the InGaPN/GaAs heterointerface due to the increase in N concentration.