Development of 100-nm-thick self-sensing nanocantilevers and characterization of the temperature dependence of the piezoresistivity and conductivity

Piezoresistive nanocantilevers are proposed for high-sensitive sensing applications such as thermal detectors, mass sensors, and magnetic resonance force microscopy. This paper describes the development of 100-nm-thick piezoresistive nanocantilevers and characterization of the temperature dependence of the piezoresisitivity and conductivity. The pieozresistive nanocantilevers are fabricated using spin-on diffusion, electron beam lithography, deep reactive ion etching, and XeF₂ vapor-phase etching techniques. A maximum longitudinal piezoresistance coefficient is obtained at 80-90 K. The shallo piezoresistor also exhibits a "quantum" metal-insulator transition phenomenon at a temperature as high as 40 K for the first time, which may prohibit its application at lower temperatures.