Growth and characterization of nitrogen-doped MgSe/ZnSeTe superlattice quasi-quaternary on InP substrates and fabrication of light emitting diodes

Superlattice quasi-quaternaries (SL-QQs), consisting of MgSe/ZnSeTe short-p eriod superlattices, were grown on InP substrates by molecular beam epitaxy with nitrogen p-doping. By changing the Mg composition (i.e., the layer th ickness ratio of MgSe in the superlattice) from 0 to 0.76, the photolumines cence peak energy at 15 K increased from 2.11 to 7.68 eV. The N-doping of M gSe/ZnSeTe SL-QQs was performed by two processes, that is by the modulation -doping into ZnSeTe and by the all-doping. For the modulation-doping, a hol e concentration of over 1 x 10(18) cm(-3) was obtained for Mg composition o f less than 0.14, with decreased monotonically with increasing Mg compositi on. The hole concentration increased by changing the doping process from th e modulation-doping to the ail-doping. Far example, the hole concentration increased from 1 x 10(15) to 3 x 10(17) cm(-3) for Mg composition of 0.4. Z nCdSe/MgZnCdSe(Te) light emitting diodes (LEDs) were fabricated using MgSe/ ZnSeTe SL-QQs as p-cladding layers having yellow emissions around 577 nm at 77 K.