Integrated fluid sensor capable of simultaneously measuring density, pressure and temperature of fluid based on micro-electromechanical system (MEMS) technology

Abstract

The invention provides an integrated fluid sensor capable of simultaneously measuring the density, pressure and temperature of a fluid based on a micro-electromechanical system (MEMS) technology. The integrated fluid sensor comprises a substrate which is provided with a cavity, wherein a permanent magnet is arranged on an internal wall of the base; an integrated sensor chip and a glass base are packaged together and then packaged at the bottom of the substrate; a liquid through hole through which the fluid flows in and out is formed in the bottom of the substrate; an opening which is communicated with the liquid through hole is formed on the glass base and used for immersing the substrate into the fluid; the integrated sensor chip is connected with a printed circuit board (PCB) adapter plate through a pad of the integrated sensor chip and then output through a signal line; the integrated sensor chip comprises a density sensor chip, a pressure sensor chip and a boron-doped thermosensitive resistor which is integrated on the surface of the density sensor chip; the density sensor chip introduces an alternating current through two pads on the density sensor chip; and the pressure sensor chip has a distributed beam film structure. The integrated fluid sensor can measure the density, pressure and temperature of the fluid at the same time, and has higher sensitivity and lower non-linearity. The anti-interference performance of the sensor is improved.

Description

technical field [0001] The invention relates to a fluid sensor, more precisely, an integrated fluid sensor for simultaneously measuring fluid density, pressure and temperature based on microelectromechanical system (MEMS) technology. Background technique [0002] Density is an important parameter index of fluid. In petrochemical, pharmaceutical, environmental protection and other fields, the accuracy of fluid density measurement directly determines the production cost and product quality. With the development of microelectromechanical systems (MEMS) technology, fluid density sensors based on silicon microchips have been extensively studied. [0003] However, current fluid density sensors measure fluid density while ignoring other factors that affect fluid density, such as fluid temperature and ambient pressure. The same fluid has different densities at different temperatures and pressures. Traditional fluid density sensors need to use pressure sensors and temperature sensor...

AI Technical Summary

Problems solved by technology

However, the island membrane structure sacrifices the sensitivity of the sensor on the basis of improving linearity and reducing deflection. The loss of sensitivity can only be compensated by increasing the size of the sensor, and the "hard core" has a considerable mass compared to the diaphragm, which is easily affected by The interference of the acceleration signal affects the output of the signal

The beam-membrane structure uses the beam formed by front corrosion and the membrane formed by corrosion from the back to achieve stress concentration. Reducing the nonlinearity of the sensor also reduces the sensitivity of the sensor

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