Polymer Coated Capacitive Microintegrated Gas Sensor

Detection of volatile organic compounds (VOCs) is important for various environmental and industrial applications such as alarm devices for pollution or building control purposes. The feasibility of smart capacitive chemical micro sensors in CMOS technology has already been assessed [I]. The objective of the current investigation was to elabo rate an analytical model for the gas/polymer interaction and to compare FEM simulations and measurements. In order to develop a model for the interactions between VOCs and the polymer layers, systematic measurementsof various parameters affecting the sensing layer were carried out. The efforts were concentrated on commercially avail able polyetherurethane (PUT, Thermedics Inc., USA), as the sensitive layer.