A Three Dimensional Thermal Sensor Based on Single-Walled Carbon Nanotubes

We present a novel three-dimensional thermal sensor based on Single-Walled Carbon Nanotubes (SWNTs) utilizing dielectrophoretic (DEP) assembly. The sensor is fabricated using a hybrid assembly technique combining top down (fabrication of the microplatform) and bottom up (DEP assembly) approaches. Encapsulating the structure with a thin (1mum) parylene layer protects it from the environment and also improves the contact resistance. Both single and multi finger assembly electrode structures have been utilized to manufacture the 3D thermal sensor and its thermal sensitivity is measured with a heated chuck. The resistances of the structures decrease more than 10% across a temperature range from 25degC to 65degC. The temperature coefficient of resistance for the SWNT-based thermal sensor is measured and ranged from -0.154 to -0.24% for the single electrode device and varied from -0.3 to - 0.57% for the multielectrode device.

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