VO2 Switch for Electrostatic Discharge Protection

On-chip protection from electrostatic discharge (ESD) and electrical overstress (EOS) is a continuous challenge in the semiconductor industry, requiring significant design costs and die space. Insulator-metal transition (IMT) materials like vanadium dioxide (VO
₂
) could be used as bidirectional, compact voltage snapback devices for ESD protection that are not required to be in the front-end silicon. However, the reliability and response of these materials to ESD is not yet well studied. Here, we perform transmission line pulse (TLP) tests on thin film (50 - 150 nm) VO
₂
devices. These can repeatedly sustain high currents in their metallic state, but still return to insulating once an ESD event is over. Devices with widths from 5 to 50 μm can carry a maximum current (I
_t2
) from ~1 to over 10 A, equivalent to ~1 to 15 kV of ESD protection. Furthermore, the snapback voltage can be engineered by varying the device length. These results suggest that IMT materials could be promising for use in on-chip ESD/EOS protection.