Single capacitance/conductance sensors

Single wall carbon nanotube (SWNT) network sensors were prepared as previously described (7-9). The carbon nanotube network (CNN) sensors were spray coated with a 0.1% by weight solution of polymer to a thickness of approximately 100 nm. These CNN sensors can be monitored simultaneously in capacitive and resistive mode. The capacitance was measured by applying a 0.1 V, 30 kHz, AC voltage between a conducting Si substrate and a S T network deposited on a thermal SiOa layer. The induced AC current was measured using a Stanford Research Systems SR830 lock-in amplifier. 

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