Research / 2020 / Article / Fig 7

Review Article

Nanoelectromechanical Sensors Based on Suspended 2D Materials

Figure 7

Hall sensor: (a) fabrication method of the suspended membrane (according to Figure 1) and (b, c) example device [146] and readout of an example device [146]. Gas sensor: (e) fabrication of the suspended membrane and ribbon and (f) example device [244]. (g, h) Working principle: gas molecules adhere to the (functionalized) 2D material and alter its resistance via electronic or chemical interactions. (i, j) Readout of an example device [248] and (k) typical sensor response plot of MoSe2 sensors depending on electron-donating/withdrawing gas [110]. Mass sensor: (l) fabrication of the suspended membrane, (m) example device, and (n, o) working principle: by measuring the resonance frequency, the mass change of the membrane is derived. (p) Extracted mass and tension of the membrane during multiple loading cycles [83]. Bolometer: (q) fabrication of the suspended membrane and ribbon and (r) example device [266]. (s, t) Working principle: when radiation heats the membrane, this alters its tension and causes a shift in mechanical resonance frequency. (u) Readout of an example device with a graphene membrane [266].