Silicon nanowire sensor array using top–down CMOS technology

The paper elaborates the silicon nanowire (SiNW) arrays fabrication using standard CMOS compatible technologies (top–down) with each array consisting of 100 wires, which are individually electrically measurable for their conductance and facilitating statistical analysis. To facilitate real-time analysis, the arrays are integrated with micro-fluidics for the delivery of various chemicals for surface modification, buffer solutions, bio-molecules/analytes, etc. The silicon nanowires are also presented as nano-temperature sensors in two configurations, i.e. as resistance temperature detector (RTD) and diode temperature detector (DTD) types. RTD type sensors have shown temperature coefficient of resistance (TCR) values ∼7500 ppm/K which are enhanced beyond 10,000 ppm/K by the application of back-bias. DTD type sensors using nanowires have recorded more than one order variation in reverse-bias current, in the temperature range of 293–373 K. Both the types of nano-temperature sensors are highly sensitive and can be integrated with other bio-chemical sensors in lab-on-chip devices. Nanowire array fabrication details in particular as nano-temperature sensor are elaborated here along with their characterization.