MEMS stands for Micro Electro-Mechanical Systems and is sometimes referred to as "Micro-machine" in Japan or MST (Micro System Technology) in Europe. MEMS devices are typically manufactured using a silicon fabrication process similar to those used for standard electronic semiconductor devices.

The micro-mechanical structure of a MEMS device is processed at a micron to sub-millimeter scale on Silicon substrate and is then used in sensor, actuator, or other applications. Today this technology is being considered for use in super high density 3-dimensional packaging techniques such as CoC (Chip on Chip) or WoW (Wafer on Wafer).