Design and Modeling of a CNT-CMOS Low-Power Sensor Chip

Multi-walled carbon nanotubes (MWCNTs) has proved to be good sensing elements for many purposes including flow variations sensing and chemical vapor sensing. However, they are not used in real applications due to the cost and size of the complex equipments required to measure the response of MWCNTs. The authors proposed a novel methodology to integrate MWCNTs sensors on commercial complementary metal-oxide semiconductor (CMOS) processed chips using dielectrophoresis (DEP). The response of MWCNTs sensors will be measured by CMOS circuit on the same substrate. Using our proposed methodology, a low cost, compact and ultra-low power MWCNTs sensor could be built and ready for commercial applications. In this paper, the authors discuss the issues on MWCNTs resistance measurement and integration of MWCNTs sensing elements -issues that will critically affect the design of the circuit components on the CMOS chip. A 0.35mum CMOS prototype will be made to demonstrate the feasibility of such CNT-CMOS integration. Simulation results and implementation details will be given.