InPlane and OutofPlane MEMS Piezoresistive Cantilever Sensors for Nanoparticle Mass Detection In this study, we investigate the performance of two piezoresistive microelectromechanical system (MEMS)based silicon cantilever sensors for measuring target analytes (i.e., ultrafine particulate matters). We use two different types of cantilevers with geometric dimensions of 1000 xc3x97 170 xc3x97 19.5 xc2xb5m3 and 300 xc3x97 100 xc3x97 4 xc2xb5m3, which refer to the 1st and 2nd types of cantilevers, respectively. For the first case, the cantilever is configured to detect the fundamental inplane bending mode and is actuated using a resistive heater. Similarly, the second type of cantilever sensor is actuated using a meandering resistive heater (bimorph) and is designed for outofplane operation. We have successfully employed these two cantilevers to measure and monitor the changes of mass concentration of carbon nanoparticles in air, provided by atomizing suspensions of these nanoparticles into a sealed chamber, ranging from 0 to several tens of xc2xb5gm3 and oversize distributions from 10 nm to 350 nm. Here, we deploy both types of cantilever sensors and operate them simultaneously with a standard laboratory system (Fast Mobility Particle Sizer, FMPS, TSI 3091) as a reference.

SimulationBased Design and Optimization of Rectangular MicroCantileverBased Aerosols Mass Sensor MicroCantilever (MCL) is a thin film structure that is applied for aerosol particle mass sensing. Several modifications to the rectangular MCL (lengthtowidth ratio, slots at the anchor, serrations at its side edges) are made to deduce the role and influence of the shape of rectangular MCLbased aerosol mass sensors and reduce gas damping. A finite element fluidstructure interaction model was used to investigate the performance of MCL. It is found that (I) the mass sensitivity and quality factor decline with the increasing of lengthtowidth ratio which alters the resonant frequency of the MCL. The optimum conditions, including the lengthtowidth ratio (xcfx83lw  5) and resonant frequency (f0  540.7 kHz) of the MCL, are obtained with the constant surface area (S  45,000 xcexbcm2) in the frequency domain ranging from 0 to 600 kHz. (II) The slots can enhance the readout signal and bring a small Q factor drop. (III) The edge serrations on MCL significantly reduce the gas damping. The results provide a reference for the design of aerosol mass sensor, which makes it possible to develop aerosol mass sensor with high frequency, sensitivity, and quality.