We investigated the effects of annealing on the electrical and thermal properties of ZTO/4H-SiC heterojunction diodes. A ZTO thin film layer was grown on p-type 4H-SiC substrate by using solution process. The ZTO/SiC heterojunction structures annealed at 500℃ show that Ion/Ioff increases from ~5.13×107 to ~1.11×109 owing to the increased electron concentration of ZTO layer as confirmed by capacitance-voltage characteristics. In addition, the electrical characterization of ZTO/SiC heterojunction has been carried out in the temperature range of 300∼500 K. When the measurement temperature increased from 300 K to 500 K, the reverse current variation of annealed device is higher than as-grown device, which is related to barrier height in the ZTO/SiC interface. It is shown that annealing process is possible to control the electrical characteristics of ZTO/SiC heterojunction diode.
