Temperature Dependant Characteristics of Zinc Oxide Nanorods Based Heterojunction Diode

Temperature-dependant characteristics of heterojunction diode made by n-ZnO nanorods grown on p-silicon substrates has been characterized and demonstrated in this paper. ZnO nanorods were grown onto the silicon substrate via simple thermal evaporation process by using metallic zinc powder in the presence of oxygen at ∼550 °C without the use of any metal catalysts or additives. The as-grown ZnO nanorods were characterized in terms of their structural and optical properties. The detailed structural studies by XRD, TEM, HRTEM and SAED revealed that the grown nanorods are well-crystalline with the wurtzite hexagonal phase and preferentially grown along the [0001] direction. The as-grown n-ZnO nanorods grown on p-Si substrate were used to fabricate p–n heterojunction diode. The fabricated p–n junction diode attained almost similar turn-on voltage of ∼0.6 V. The values of turn-on voltage and least current are same with the variations of temperature (i.e., 27 °C, 70 °C and 130 °C).