Fabrication of freestanding Pt nanowires for use as thermal anemometry probes in turbulence measurements

Abstract We report a robust fabrication method for patterning freestanding Pt nanowires use as thermal anemometry probes small-scale turbulence measurements. Using e-beam lithography, high aspect ratio (~300 nm width, ~70 µm length, ~100 thickness) were patterned on the surface of oxidized silicon (Si) wafers. Combining wet etching processes with dry processes, these successfully released, rendering them between two dioxide (SiO 2 ) beams supported Si cantilevers. Moreover, unique design bridge holding device allowed gentle release without damaging nanowires. The total time was minimized by restricting lithography to nanowires, while standard photolithography employed other parts devices. demonstrate that fabricated sensors are suitable measurements when operated in constant-current mode. A calibration output voltage and fluid velocity established over range from 0.5 5 m s −1 SF 6 atmosphere at pressure bar temperature 21 °C. sensing signal showed negligible drift period several hours. we confirmed can withstand dynamic pressures testing air room velocities up 55 .