Position-Selective Fabrication of TiO2-x Semiconductive Microline by Nanosecond Pulse Laser Modification for Gas Sensing

This paper proposes the position-selective fabrication of semiconductive TiO2−x microline by YVO4 nanosecond pulse laser modification and demonstrates its gas sensing performance for NH3. We directly fabricated TiO2−x microlines with a minimum line width of 10 μm on a TiO2 substrate by focusing laser irradiation. The microline showed systematic response as increase in the electrical resistance to NH3 gas at 40–80 ppm. A systematic fabrication of semiconductive oxide microlines with various line widths could design their gas sensitivity based on control of efficient self-heating by the applied current through the microline. Furthermore, using the advantages of the position-selective laser modification, we also fabricated a more complex zigzag patterned TiO2−x microline and demonstrated the improved gas sensitivity.