A packaging technique of pressure sensor for in vivo measurement system

Bodily pressures can provide valuable information for making a diagnosis or health monitoring. The pressure sensor is widely used to obtain bodily pressure, however, sensor drift has severely limited their application in vivo measurement system. In this paper, we report on a packaging technique for improving the stability and accuracy of the pressure sensor. Commercial piezoresistive pressure sensors are enclosed in silicone oil and then encapsulated with silicone membrane and parylene-N. The described method isolates the pressure sensor from the abominable surrounding environment and keeps the pressure in the cavity constant. In vitro tests for 40 days show that the pressure sensor packaged by this method could obtain better stability. The average baseline drift of the pressure sensor was 0.025 mmHg/week after the pressure sensor became stable.

Automated summary

This paper reports a packaging technique to improve the stability and accuracy of pressure sensors. By enclosing the pressure sensors in silicone oil and encapsulating them with silicone membrane and parylene-N, the sensors are protected from the surrounding environment and can maintain stable pressure. In vitro tests demonstrate that the packaged pressure sensors exhibit better stability with an average baseline drift of 0.025 mmHg/week.