Investigation of Chip Temperature on Response Characteristics of the Humidity Sensor From ppm to %RH

摘要

Many research articles are reported on humidity measurement in the literature. But there is no critical study of temperature on the response characteristics of the humidity sensors, particularly in ppm-level. Developing an experimental set up for studying the temperature effect is challenging as the variation of the ambient temperature not only varies the response of the sensor but also the humidity level inside the chamber. Commercial humidity-controlled chamber to maintain humidity and temperature is bigger in size and costly. Purposes of the present work are (i) to investigate the chip temperature effect on the characteristics of metal oxide humidity sensors in ppm level and in %RH (ii) to enhance the sensitivity of a sensor by suitably controlling its temperature in ppm level (iii) to refresh the sensor by intermittent heating pulse. A suitable experimental set up is also developed to study the temperature effect on the sensors. The chip temperature may be another method to enhance the sensitivity in low ppm moisture detection.