Mavroidis, Constantinos, Jung, Yung Joon, Khanieheh, Azedeh
There are many current and future temperature measurement applications that would benefit significantly from a commercially available, low power consuming, ultra-small-scale temperature sensor. The superior material properties of carbon nanotubes (CNTs) have suggested that it is possible to create a device that will meet these requirements and also have better performance when compared to devices currently available in the market However, there are currently no commercially available temperature sensors that make use of the advantages in using CNTs as a small-scale sensing element due to relatively high cost of manufacturing. This report outlines the design, fabrication, and testing of a novel CNT-based Temperature Sensor encapsulated in a thin film of flexible Parylene C. The design employs a single-walled carbon nanotube (SWNT) network between two micro-scale electrodes as the sensing element. The resulting device exploits the extremely small size of SWNTs as well as their superior thermal and electrical properties by deriving the temperature based on a change in electrical resistance that is induced by thermal strain. The sensitivity of the sensor is maximized by making use of an expansion element, with high thermal coefficient of expansion, which is a novel method for regulating strain in the SWNT network, and was a key factor in relating thermal strain to electrical resistance. The sensor requires power in the microwatt rangeÃ?Â?Ã?Â¯Ã?Â?Ã?Â¿Ã?Â?Ã?Â½Ã?Â?Ã?Â¯Ã?Â?Ã?Â¿Ã?Â?Ã?Â½Ã?Â?Ã?Â¯Ã?Â?Ã?Â¿Ã?Â?Ã?Â½orders of magnitude less than that of typical micro-scale sensors. The basic concept prototype sensors being fabricated can be characterized to measure temperature and predictions can be made successfully about the improvement in overall performance of the expanding element concept, when compared against a device with it.
Department of Mechanical, Industrial, and Manufacturing Engineering
Crawford, Brendan; Esposito, Dan; Jain, Vishal; and Pelletier, David, "Flexible Carbon Nanotube Based Temperature Sensor for Ultra-Small-Site Applications" (2008). Capstone Design Program: Mechanical Engineering. Paper 55. http://hdl.handle.net/2047/d10012904
Click button above to open, or right-click to save.COinS