This abstract presents the design and fabrication of a temperature sensor based on carbon nanotubes (CNTs). The sensor is fabricated by dielectrophoretic trapping of CNTs between two nanoelectrodes. The conductance of the sensor is highly sensitive to the temperature variation which makes it suitable for applications requiring accurate measurements. In addition, fast response and good stability and durability are the important advantages of the sensors made of CNTs.

The structure of the device is shown in the figure. CNTs are trapped in between nanoelectrodes using the dielectrophoresis (DEP) technique. Dielectrophoresis is a phenomenon in which a force is applied to a dielectric particle when it is exposed to a non-uniform electric field [1]. Although dielectrophoresis provides an accurate method for trapping materials in a predefined area, this method suffers from a costly fabrication process when dealing with nanomaterials. In this study, we used a standard photolithography method to fabricate low-cost devices and an electronic circuit is used to apply the required electric field and monitor the gap for the presence of CNTs.

The device fabrication process starts with the pattering and depositing gold nanoelectrodes and contacts using the photolithography method. The process is followed by converting the surface of the device except for the nanoelectrodes area and connection pads with an insulation layer of Silicon nitride. Since the electrodes are thin (50 nm) and CNTs are flexible, fabrication on the flexible substrates is also feasible.

References

[1] T. Ghomian et al., "High‐Throughput Dielectrophoretic Trapping and Detection of DNA Origami," Advanced Materials Interfaces, vol. 8, no. 5, p. 2001476, 2021.