Current transport studies of ZnO/p-Si heterostructures grown by plasma immersion ion implantation and deposition.

Rectifying undoped and nitrogen-doped ZnO/p-Si heterojunctions were fabricated by plasma immersion ion implantation and deposition. The undoped and nitrogen-doped ZnO films were n type (n∼1019 cm-3) and highly resistive (resistivity ∼105 Ω cm), respectively. While forward biasing the undoped-ZnO/p-Si, the current follows Ohmic behavior if the applied bias Vforward is larger than ∼0.4 V. However, for the nitrogen-doped-ZnO/p-Si sample, the current is Ohmic for Vforward<1.0 V and then transits to J∼V2 for Vforward>2.5 V. The transport properties of the undoped-ZnO/p-Si and the N-doped-ZnO/p-Si diodes were explained in terms of the Anderson model and the space charge limited current model, respectively. [ABSTRACT FROM AUTHOR]