Effect of oxygen partial pressure on the electrical properties of the La0.5Sr0.5CoO3/Al-doped ZnO thin film heterojunctions

In this study, p–n heterojunction with La0.5Sr0.5CoO3 (LSCO) and 3 wt.% Al-doped ZnO (AZO) thin films were prepared by radio frequency (r. f.) magnetron sputter. Heterojunction was made by stacking the p-type LSCO thin film on the pre-annealed n-type AZO thin film under a flow of different Ar:O2 sputter gas ratio during deposition. The thickness of AZO and LSCO films is about 500 and 200 nm, respectively. The LSCO/AZO heterojunction shows somewhat lattice match between LSCO films with AZO films from XRD and TEM investigation. Rectifying behavior of the heterojunctions in the range of − 8 to 8 V for all of the samples are examined. The diode has the lowest resistance under Ar:O2 sputter gas ratio of 10:5 (sccm). The turn-on voltage of the diodes is obtained from the I–V curve was around 1.5 V.