© 2020 Elsevier B.V.We report a facile but effective method to produce heterojunction diodes by simply depositing AGZO thin films on Si substrates, and investigate the influences of the thickness of AGZO layer on diode performances. AGZO layers are subjected to device studies to find a correlation between the thickness of AGZO and diode performances. The results suggest that a variation in the thickness of AGZO insignificantly affects structural, morphological, and optical properties while it can effectively enhance characteristics of devices. The diode with 125 nm of AGZO renders an improvement in the diode performance. It shows remarkable rectification properties with a Iforward/Ireverse of 8146 at ± 4 V, ∅B of 0.73 eV, and Rs of 0.89 kΩ. Compared to the values diode performances for undoped, Al-doped and Ga-doped ZnO based devices in the literature, undoubtedly, our results are promising, indicating that co-doped layers should also be considered in fabrication of thin-film based diodes.