Narrow Results

Measurements of the Casimir–Lifshitz (dispersion) forces at distances below 50 nm are difficult due to the snap-in effect, and precision is poor due to increasing relative uncertainty in the distance. In this paper, a method of adhered cantilever that avoids the loss of stability is used to measure the interaction energy between Si and Ru surfaces in direct contact. Background capillary and short-range interactions are strongly suppressed because surface roughness significantly deviates from a normal distribution. Electrostatic interaction is not fully compensated, but the potential is limited to a value less than 29.8mV. Adhesion energy is measured directly, and the average equilibrium distance is predicted theoretically. The ability to achieve high precision in this type of experiment is demonstrated.

A methodology of 3D self-assembly is presented, pairing neighboring electromechanical system (MEMS) elements to create Yin or Yang-shaped structures. After sacrificial layer removal and during the sequential drying process, (i) surface tension forces bring the neighboring MEMS shutter blades very close to each other, and (ii) Casimir forces and van der Waals forces keep the blades attached tightly. Various experimental trials to reopen the tight attachments are reported. The relative significance of fundamental forces during 1D and 3D scaling of the system is presented.