Design and fabrication of tunable inductors based on vanadium dioxide thin film

Vanadium dioxide (VO2) is a well-known phase change material that shows a metal to insulator transition at temperatures near 68 °C. It has many potential applications in science and engineering. In this study, VO2 thin film based planar spiral tunable inductors were designed and fabricated on a sapphire substrate. This approach can be a potential solution for reconfigurable RF/microwave wireless communication systems. According to the experimental results, fabricated inductors show a 43.4 % (from 2.19 nH to 1.24 nH) tuning range at 2 GHz when the VO2 thin film layer undergoes the insulator-to-metal transition from room temperature to temperatures above the transition. This result confirms that the proposed inductor structure was fully functional with the successful inductance tuning capability.