Trap Exploration in Amorphous Boron-Doped ZnO Films
AbstractThis paper addresses the trap exploration in amorphous boron-doped ZnO (ZnO:B) films using an asymmetric structure of metal-oxide-metal. In this work, the structure of Ni/ZnO:B/TaN is adopted and the ZnO:B film is deposited by RF magnetron sputtering. The as-deposited ZnO:B film is amorphous and becomes polycrystalline when annealing temperature is above 500 °C. According to the analysis of conduction mechanism in the as-deposited ZnO:B devices, Ohmic conduction is obtained at positive bias voltage because of the Ohmic contact at the TaN/ZnO:B interface. Meanwhile, hopping conduction is obtained at negative bias voltage due to the defective traps in ZnO:B in which the trap energy level is lower than the energy barrier at the Ni/ZnO:B interface. In the hopping conduction, the temperature dependence of I-V characteristics reveals that the higher the temperature, the lower the current. This suggests that no single-level traps, but only multiple-level traps, exist in the amorphous ZnO:B films. Accordingly, the trap energy levels (0.46–0.64 eV) and trap spacing (1.1 nm) in these multiple-level traps are extracted. View Full-Text
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Chiu, F.-C.; Chiang, W.-P. Trap Exploration in Amorphous Boron-Doped ZnO Films. Materials 2015, 8, 5795-5805.
Chiu F-C, Chiang W-P. Trap Exploration in Amorphous Boron-Doped ZnO Films. Materials. 2015; 8(9):5795-5805.Chicago/Turabian Style
Chiu, Fu-Chien; Chiang, Wen-Ping. 2015. "Trap Exploration in Amorphous Boron-Doped ZnO Films." Materials 8, no. 9: 5795-5805.