Dielectrophoretic Trapping of Carbon Nanotubes for Temperature Sensing

Conventional sensors are rapidly approaching efficiency limitations at their current size. In designing more efficient sensors, low dimensional materials such as carbon nanotubes (CNTs), quantum dots, and DNA origami can be used to enable higher degrees of sensitivity. Because of the high atomic surface to core ratio, these materials can be used to detect slight changes in chemical composition, strain, and temperature. CNTs offer unique advantages in different types of sensors due to their electromechanical properties. In temperature sensing, the high responsiveness to temperature and durability can be used to produce an accurate, reliable sensor in even extreme temperatures. This study aimed to utilize CNTs to reliably produce a temperature sensor in an easily reproducible method. CNTs were trapped and immobilized using dielectrophoresis to bridge two gold nanoelectrodes on a sapphire substrate. The fabricated device showed high sensitivity to temperature variation, with a measured resistive sensitivity of 2.96 E-3/K, a higher sensitivity than similar thin film sensors. This study will help further development of CNT-based temperature sensors