Low-range and high-sensitivity micro-electromechanical system (MEMS) pressure sensor and manufacture method thereof

Abstract

The invention discloses a low-range and high-sensitivity micro-electromechanical system (MEMS) pressure sensor which comprises a monocrystalline silicon layer (1), a porous silicon / silicon composite membrane structure (6), a porous silicon voltage dependent resistor (7) and a metal layer (8), wherein the back surface of the monocrystalline silicon layer (1) is provided with a concave cavity; the porous silicon / silicon composite membrane structure (6) is formed in the concave cavity in the back surface of the monocrystalline silicon layer (1); the porous silicon voltage dependent resistor (7) is formed on the front surface of the monocrystalline silicon layer (1); the metal layer (8) is deposited on the porous silicon voltage dependent resistor (7) and has a function of metal interconnection. The invention further discloses a manufacture method of the low-range and high-sensitivity MEMS pressure sensor. Porous silicon materials have excellent piezoresistive performance and mechanical performance, and therefore, the porous silicon MEMS pressure sensor adopting the structure can keep degree of linearity and improve sensitivity simultaneously, and can be applied within a superlow pressure range by means of flexible structure design.

Description

technical field [0001] The invention belongs to the technical field of MEMS pressure sensor manufacturing, and in particular relates to a low-range high-sensitivity MEMS pressure sensor based on a double-sided porous silicon material and a manufacturing method thereof. Background technique [0002] MEMS pressure sensors overcome the defects of traditional mechanical pressure sensors, and have the outstanding advantages of miniaturization, high sensitivity, good stability, low cost, easy integration and intelligence. Sensitivity and nonlinearity are the most important technical parameters of pressure sensors. Its sensitive mechanism is based on the mechanical deformation and stress of the pressure-sensitive film caused by the measured pressure. Typical forms include piezoresistive, capacitive and resonant. Compared with capacitive and resonant pressure sensors, the manufacturing process and signal processing circuit of piezoresistive pressure sensors are simple, and there is...

AI Technical Summary

Problems solved by technology

For example, based on the research on the piezoresistive properties of single-walled and multi-walled carbon nanotubes, carbon nanotube low-pressure sensors are applied to touch screens or flexible displays. The compatibility of carbon nanotubes and device preparation processes is a difficult point, and the distance There is still a distance between the practical requirements of area and batch preparation

Images