A Spray Processed Harsh Environment Humidity Sensor for Detecting Relative Humidity in Microfluidic Gas Flows

Description

Four different custom made paints based on different compositions of carbon black (either pure or in a polyamide-imide matrix) were used to spray process a resistive type humidity sensor. The polyamide-imide composite resistors show good mechanical, chemical and high temperature stability up to 250 °C. Characterization of the resistors was done in a climatic chamber where the relative humidity was ramped from 28 to 90% and the temperature from 25 to 85 °C. The highest relative change in resistivity observed was 0.11 at a temperature of 85 °C. All tested samples showed an increase in humidity sensitivity with increasing temperature. Subsequently the temperature characteristic of the resistors was recorded up to 250 °C, where two of the tested paints showed a conversion from negative to positive temperature coefficient.

Period	28 Feb 2018
Event title	5th European Conference on Microfluidics
Event type	Conference
Location	FranceShow on map