MEMS piezoresistive pressure sensor with patterned thinning of diaphragm

Abstract

Purpose The purpose of this study is to find a new design that can increase the sensitivity of the sensor without sacrificing the linearity. A novel and very efficient method for increasing the sensitivity of MEMS pressure sensor has been proposed for the first time. Rather than perforation, we propose patterned thinning of the diaphragm so that specific regions on it are thinner. This method allows the diaphragm to deflect more in response with regard to the pressure. The best excavation depth has been calculated and a pressure sensor with an optimal pattern for thinned regions has been designed. Compared to the perforated diaphragm with the same pattern, larger output voltage is achieved for the proposed sensor. Unlike the perforations that have to be near the edges of the diaphragm, it is possible for the thin regions to be placed around the center of the diaphragm. This significantly increases the sensitivity of the sensor. In our designation, we have reached a 60 per cent thinning (of the diaphragm area) while perforations larger than 40 per cent degrade the operation of the sensor. The proposed method is applicable to other MEMS sensors and actuators and improves their ultimate performance. Design/methodology/approach Instead of perforating the diaphragm, we propose a patterned thinning scheme which improves the sensor performance. Findings By using thinned regions on the diaphragm rather than perforations, the sensitivity of the sensor was improved. The simulation results show that the proposed design provides larger membrane deflections and higher output voltages compared to the pressure sensors with a normal or perforated diaphragm. Originality/value The proposed MEMS piezoelectric pressure sensor for the first time takes advantage of thinned diaphragm with optimum pattern of thinned regions, larger outputs and larger sensitivity compared with the simple or perforated diaphragm pressure sensors.

Sensitivity of Piezoresistive Pressure Sensors to Acceleration

“…If it responds to static acceleration, it must also respond to dynamic acceleratio lated to the movement of the sensor relative to the ground, and it is, as described in E tion (3). Therefore, in addition to the force that is responsible for the pressure, the m uring structure is also influenced by the force associated with accelerations.…”

“…The authors suggest using the sensor in devices with touch sensors. From the point of view of microstructure development, a very interesting solution is shown in article [3]. The article presents a new solution for the structure of the MEMS piezoresistive sensor.…”

Ultrahigh-Sensitivity Pressure Sensor With Graphene Aerogel Electrodes

“…The recent literature contains numerous references that describe innovative pressure sensors . Those sensors usually use either the principle of piezoresistivity [3,4,5,6,7,8,9,10,12,14,15,17,21] (see Appendix A for performance parameters), or capacitance variation [11,13,16,18,19,20,22,23] (see Appendix A). The advantage of the new sensor introduced in this paper is the excellent sensitivity to very low pressures (0.1 Pa to 10 Pa).…”

Study of the thermal drifts on the piezoresistivity using mobility model and finite difference method of electric heater

“…However, they often suffer from the thermal drift. The study of electric heater effect in these sensors types is important to optimize the output characteristics drift [5]- [8]. As a result, several previous research papers have been carried out in this domain in order to lessen this effect, when the bridge is powered by an electric tension.…”