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Enhanced sensitivity, precise measurements and accuracy are the key factors to identify the performance of any sensor. In this paper, p-polycrystalline silicon micro-pressure sensor has been designed which works on the principle of piezoresistive effect. A theoretical modeling and computational simulation of the circular Si-diaphragm have been performed through the extensive study of stress and frequency response with the help of finite element method (FEM) within the framework of COMSOL. For a thin diaphragm ($\sim$50 $\mu$m), the Eigen frequency and the frequency generated in a diaphragm under the influence of pressure has been optimized within the pressure range from 1–25 kPa. The modes of vibrations generated in the diaphragm have been optimized at wide-frequency range $\sim$200–800 kHz at various pressure values. The findings of the presented research have suggested that for a $\sim$50 $\mu$m thin diaphragm, the optimized fundamental frequency is $\sim$310 kHz for showing better piezoresistive response which results into enhanced sensitivity. Moreover, the simulation results show that for the designed sensor, the pressure sensitivity of $\sim$11.51 mv/psi has been conveyed.

Silicon-based Microelectromechanical System (MEMS) pressure sensors are extensively used and have the advantages of high accuracy and miniaturization. Despite this, due to inherent material limitations, they are not easily able to withstand high temperatures greater than 150°C. To overcome this disadvantage, Silicon Carbide (SiC) is the preferred material because it has excellent thermomechanical properties and operates above 600°C. Piezoresistive pressure sensors made of Silicon Carbide are ideally able to detect pressures beyond 600°C. Our work presents MEMS Single turn meander-shaped piezoresistive pressure sensor on a circular SiC diaphragm for high pressure applications of pressure range 0–40MPa in harsh environment. This work models and analyses the piezoresistive pressure sensor characteristics using an analytical modeling and simulation method to choose the best design. To ascertain its sensitivity, expressions are computationally simulated with MATLAB software using the thin plate and small deflection theory. To evaluate the viability of the model, COMSOL Multiphysics simulation is used. When compared to recent studies, our proposed sensor provides a sensitivity of near about 5.4mV/V/MPa across a pressure range of 0–40MPa.

Micro-Electro-Mechanical Systems (MEMS) technology has been heavily incorporated into fabrication of sensors due to its undoubtful advantages such as efficient form-factor, low-power consumption and less bulk manufacturing cost. One of the first sensors to undergo transformation in the micro-scale has been the pressure sensor. Pressure sensors are used excessively in various fields such as automobile, aerospace, aviation, biomedical, consumer electronics, etc. Various researches are being conducted to optimize the design of MEMS-based pressure sensors to meet the specific requirements of different fields. This work presents a piezoresistive pressure sensor design with striated-shaped piezoresistors instead of the conventional bar-shaped piezoresistors. Such a configuration allows positioning the short arms of the striated design effectively on the narrow high stress regions. The piezoresistors are embedded on a circular diaphragm. The performance advantage of such a design is validated through analytical models and numerical simulations. Finite Element Analysis (FEA) is deployed using COMSOL Multiphysics software to achieve precise simulation results. The results are then compared to the existing literature. The proposed design achieves a sensitivity of 40.365 mV/V/MPa under a pressure range of 0–1 MPa. The proposed design performs better than existing literature and can be used in applications that require high sensitivity over a long pressure range, for example, in barometric altimeters.

Due to advancements in Micro-Electro-Mechanical Systems (MEMS) fabrication technologies, researchers are incorporating numerous innovations in the design of capacitive pressure sensors (CPS). This work aims to present a novel CPS design using a plano-convex substrate to enhance the capacitance and sensitivity. Diaphragm deflection occurs due to its elastic property when pressure is applied to the diaphragm. This deflection reduces the distance between the diaphragm and substrate, thereby remarkably increasing capacitance. The Plano-Convex design offers added advantages of increased contact area between the diaphragm and substrate under applied pressure, hence significantly enhancing sensor sensitivity and range. More efficient and miniaturized CPSs are in high demand in medical instrumentation, aerospace, aviation, power plants and automotive industries. This work presents all the required mathematical calculations, modeling and simulations to support the proposed design. The diaphragm deflection simulation concerning pressure is conducted using COMSOL Multiphysics, while MATLAB is employed for analytical simulations related to changes in capacitance and capacitive sensitivity.