Effect of MgZnO barrier layer on the UV emission of n-ZnO/p-Si heterojunction diodes

► MgZnO is firstly used as the current-blocking layer in ZnO/Si structures. ► Inserting MgZnO layer could improve the quality of the upper ZnO layer. ► Under forward bias, prominent UV emission around 388 nm is observed. ► We obtain a higher output power than n-ZnO/p-Si structure by almost 31%.