Stiction

Stiction (a portmanteau of the words static and friction)[1] is the force that needs to be overcome to enable relative motion of stationary objects in contact.

[2] Any solid objects pressing against each other (but not sliding) will require some threshold of force parallel to the surface of contact in order to overcome static adhesion.

Similarly, when trying to accelerate rapidly (particularly from a standing start) an overenthusiastic driver may "squeal" the driving wheels, but this impressive display of noise and smoke is less effective than maintaining static contact with the road.

A car on a slippery surface can slide a long way with little control over orientation if the driver "locks" the wheels in stationary positions by pressing hard on the brakes.

Consider a mechanical element slowly increasing an external force on an assembly at rest that is designed for the relative rotation or sliding of its parts in contact.

Any part of the assembly that can elastically bend, even microscopically, and exert a restoring force contributes a spring moment.

[5] During surface micromachining, stiction or adhesion between the substrate (usually silicon-based) and the microstructure occurs during the isotropic wet etching of the sacrificial layer.

Stiction is often circumvented by the use of a sublimating fluid (often supercritical CO2, which has extremely low surface tension) in a drying process where the liquid phase is bypassed.