Solid-state based temperature sensor is gaining attention due to its flexibility in design and high accuracy. ZnO is a semiconductor material which is inexpensive and suitable to be used in a harsh environment such as in dangerous radiation and high temperature. ZnO nanorods are synthesized using hydrothermal technique with three different reaction times, i.e. 20, 30 and 40 hours. The average areas of ZnO nanorods produced decreased with increasing of reaction times. The non-uniformity of ZnO nanorods grown is decreased from 32% to 31.25% with increasing reaction times. The I-V characteristics are measured with different temperatures from 27°C to 300°C. As the temperature increased, the resistance of the nanorod device decreased. The best sensitivity towards temperature achieved with nanorods produced for 20-hours reaction times which is 1.72 ?/°C.
