We proposed BeZnTe/ZnSeTe superlattice quasi-quaternaries (SLQQs) as an active layer material replaced with BeZnSeTe quaternaries for yellow/green light emitting devices. BeZnTe/ZnSeTe SLQQs with various layer thickness combinations of BeZnTe and ZnSeTe were grown on InP substrates by a molecular beam epitaxy (MBE). In photoluminescence (PL) measurements at room temperature, high PL intensities were obtained for the SLQQs compared with BeZnSeTe. The peak wavelength was controlled from 589 to 480 nm by changing the layer thickness combination (BeZnTe/ZnSeTe) from 1 monolayer (ML)/20 ML to 4 ML/2 ML Applying the SLQQ for the active layer, LEDs were fabricated on n-type InP substrates. Single-peak yellow electroluminescence at 584 nm was observed with the full wave half maximum (FWHM) of 105 meV. (c) 2013 Elsevier B.V. All rights reserved.