Vanadium Dioxide Microactuators

The Berkeley Lab microactuator is made of bimorph structures based on vanadium dioxide, an advanced material that responds to heat, electric current, and light. In both ambient and aqueous conditions, the actuators bend with exceedingly high

• displacement-to-length ratios, on the order of 1 in the sub-100 μm length scale, and
• work densities, 0.63 - 7.0 J/cm³,

at frequencies up to 6 kHz.

Microactuators are essential for converting external stimuli, such as heat, electricity, and light, into mechanical motion in such advanced technologies as MEMS and artificial muscles. The Berkeley Lab technology’s integrated designs of two- or three-dimensional geometries are customizable for these applications as well as for microfluidics used in drug delivery systems.

• High amplitude, high speed, and high force actuation
• Operates in ambient or aqueous conditions
• Energy efficient
• Made of nontoxic and abundant materials
• High stability and durability
• Easily scalable and customizable

• Microelectromechanical systems (MEMS)
• Microrobotics
• Microfluidics
• Drug delivery
• Artificial muscles
• Smart and adaptive materials

Hatt, Alison, “Flexing fingers for micro-robotics: Berkeley Lab scientists create a powerful, microscale actuator,” Berkeley Lab News Center, December 17, 2012.

Kevin Wang, Chun Cheng, Edy Cardona, Jingyang Guan, Kai Liu, Junqiao Wu, “Performance limits of micro-actuation with vanadium dioxide as a solid engine,” ACS Nano, 7, 2266 (2013).

Kai Liu, Chun Cheng, Zhenting Cheng, Kevin Wang, Ramamoorthy Ramesh, Junqiao Wu, “Giant-Amplitude, High-Work Density Microactuators with Phase Transition Activated Nanolayer Bimorphs,”Nano Lett., 12, 6302 (2012).