MEMS Gas Sensors with Metal-Oxide Semiconductor Materials Patterned at Wafer-Level by Photolithography Technique

Many types of MEMS gas sensors based on metal-oxide semiconductors (MOS) are reported in recent years. For the fabrication of the gas sensors, it is still a big challenge to achieve wafer-level patterning and good compatibility for the MOS thin film architecture. In this paper, we report a wafer-level patterning method using photolithography to increase the patterning efficiency. When compared with devices using dip-coating, our devices show comparable response and excellent reproducibility. Besides, we prove the feasibility of this method for patterning different materials onto various electrodes structure. This method provides a potential for mass production of MEMS gas sensors where high efficiency and throughout are crucial.