Green II–VI light emitting diodes with long lifetime on InP substrate

Abstract

We demonstrate that the quaternary compound ZnMgSeTe can be grown by molecular beam epitaxy in reasonable quality. For layers with energy gaps as high as 3.1 eV, nitrogen doping leads to free hole concentrations around 1018 cm−3. In combination with n-ZnMgCdSe, this material allows the fabrication of II–VI diodes lattice matched to InP substrate. Light emitting diodes containing a tensile strained ZnCdSe quantum well in ZnMgCdSe emit green light when operated in forward direction. In contrast to diodes with a comparable density of extended defects grown on GaAs substrate, these diodes show no formation of dark line defects and a lifetime which is about three orders of magnitude longer.