Tuning of ZnSe-GaAs band discontinuities in heterojunction diodes

The conduction band offset in ZnSe/GaAs n-p heterodiodes was determined from measurements of the low-temperature tunneling current of photoinjected carriers. We found widely different discontinuities for heterojunctions fabricated with different Zn/Se flux ratios, with conduction band offsets as high as 0.75 eV for Se-rich interfaces, and as low as 0.26 eV for Zn-rich interfaces.