TEOS plasma polymerized films: Impact of clustered material in humidity measurement

This work aims to humidity and VOCs measurement using TEOS films or TEOS/HFE composites. Films, exposed or not to ultraviolet, were tested on cycles of relative humidity ranging from 25% to 85% and VOCs interference were also evaluated. TEOS films showed good reproducibility up to 85% relative humidity but quick reaction on 90%. The best detection limit was 100 ppm, using TEOS films exposed to UVC and TEOS/HFE composites show sensitivity of 4 Hz/% humidity, but interdigitated electrodes quickly saturate. VOCs were detected in the 1% w/w in air and do not interfere in the relative humidity detection.