Characteristics and Application Fields of Diffused Silicon Pressure Sensors

The diffused silicon pressure sensor uses the principle of piezoresistive effect and adopts integrated process technology to dope and diffuse along the characteristic crystal direction of the single crystal silicon wafer to make a strain resistor to form a Wheatstone bridge. By using the elastic mechanical properties of silicon materials and performing anisotropic micromachining on the same cut silicon material, a diffused silicon sensor integrating force sensitivity and force-electric conversion detection is made. The pressure of the diffused silicon pressure sensor acts directly on the diaphragm of the sensor, which is usually stainless steel or ceramic, causing the diaphragm to produce a displacement proportional to the medium pressure, and the resistance value of the sensor changes, and the electronic circuit detects this change and converts the output signal corresponding to this pressure. It has many characteristics and obvious advantages.

① Diversified appearance and structure.

② Strong anti-interference.

③ Adopting 316L stainless steel isolation diaphragm structure, the corrosion resistance is much better than that of 301 stainless steel.

④ Micro amplifier, current signal output.

⑤ High precision, after multiple stainless steel welding, a full solid-state design is achieved, which can be used for a long time in harsh environments.

⑥ High-quality terminals with good long-term stability.

⑦ Using imported diffused silicon core, the measurement is more accurate.

The application field of diffused silicon pressure sensor is very wide, ranging from industry to professional research fields. Common applications include experimental equipment such as aviation and aerospace; diving, shipbuilding and drilling platforms; petroleum, chemical and metallurgical industries; thermoelectric, metallurgy, machinery, light industry; clean energy, water treatment and building automation fields; scientific research institutes, laboratory pressure calibration, etc. However, due to the characteristics of diffused silicon sensor itself, it cannot be used for the measurement of high temperature and low temperature media.