Extended Data Fig. 3: Controlling SEA pre-stress.
From: Electronically integrated, mass-manufactured, microscopic robots
The curvature in a SEA is set by both adsorption of ions and pre-stresses built up during fabrication. Here we plot the curvature of a titanium–platinum SEA in the absence of any applied bias as a function of the titanium layer thickness. The curvature varies continuously from positive to negative as the titanium layer is increased. As the voltage is fixed to the open circuit potential, this effect is purely due to pre-stress. The sign of the curvature inverts at a titanium thickness of around 4 nm. Overall, the pre-stress provides an added level of control over the three-dimensional structure formed using SEAs and rigid panels.
