Surface Analysis and Post Thermal Treatment Process Optimization of Graphene Oxide Thin Film for Humidity Sensor Application

Graphene Oxide (GO) has the two-dimensional (2D) layered structure with lots of oxygen containing groups. In this work, GO thin film was coated on substrate with carefully prepared GO dispersion. The GO film was thermally treated by different process condition, and characterized by surface analysis methods to get the optimized process condition. After that, GO based capacitive humidity sensor structure was designed and fabricated, and the capacitance of the sensor structure was increased about seven times from ~22.5% RH% to ~85% RH%, which shows excellent sensitivity performance.