LAUSR

Abstract The photoluminescence (PL) properties of InGaN/GaN multiple quantum wells (MQWs) structures grown by metal-organic chemical vapor deposition (MOCVD) with varying hydrogen (H2) treatments after GaN cap layer growth are investigated to elucidate the role of H2 treatment in epitaxial growth. A comparison of the temperature-dependent PL spectra of the samples with and without H2 treatment shows that H2 treatment contributes to narrowing the PL linewidth and improving the homogeneity of luminescence. Moreover, the PL mapping results verify that H2 treatment facilitates the improvement of the surface and interface quality of MQWs. This may be attributed to a more homogeneous distribution of localization states in the InGaN, and the defects in MQWs are also decreased, thus enhancing the luminescence intensity. This work provides a method for improving the quality GaN-based light-emitting diodes, laser diodes and solar cells.