CMOS-compatible abrupt switches based on VO2 metal-insulator transition

We report an extensive experimental study of CMOS-compatible switches based on vanadium dioxide abrupt metal-insulator transition. We perform scaling studies to provide guidelines for optimization of the geometry of the VO₂ device for integration on CMOS circuits, discussing the trade-off between the design parameters and the effect on performance for DC and RF applications. A VO₂ thin film with resistivity varying from 5·10^-2 Ω·m in the insulating state to 1.5-10^-5 Ω·m in the conductive state allowed us to fabricate devices with actuation current ranging from 1.43 to 2.46 mA and resistance in the insulating state ranging from 5.8 kΩ to 35.9 kΩ. We identified a minimum actuation current of 5.75 μA for our technology, in a device miniaturized up to the limits of standard optical lithography. We show through RF measurements and simulations that the performance at high frequency of the switch can be improved using VO₂ thin films with higher conductivity values, even if the contrast between the two states is lower.