For gas sensing measurement the

The fundamental steps were as follows: Interdigitated (IDT) electrodes of gold with Torin 1 line-distance of 100 μm were fabricated on the 6 mm × 12 mm Al2O3 substrate via lift-off process and radio frequency (RF) magnetron sputtering. The sensing material was then deposited on the IDT electrodes via air-brush spraying and metal mask (selective area). The substrate was heated to 110 °C on a hot-plate during spraying.
2.2.