This abstract reports very high (>1014 cm−2) sheet carrier density (ns)in Zinc Oxide (ZnO) based heterostructure for low Magnesium (Mg) compositions (<0.15) in barrier layer, achieved by alloying Cadmium (Cd) in buffer layer ZnO, grown by Dual Ion Beam Sputtering (DIBS) deposition technique. © Springer Nature Switzerland AG 2019.