Introduction
Microelectromechanical systems (MEMS) operate at the microscale, which refers to structures with sizes ranging from around 1 micrometer to 1 millimeter. MEMS devices contain miniaturized mechanical and electro-mechanical elements that can perform sensing, actuation, and control functions.
The classic defintion of MEMS is any device that,
- Is fabricated using extensions of microelectronic processing (film deposition, photolithography, etching).
- Contains mechanically moving parts or permits fluids motion through its components.
- May also contain microelectronic circuitry to control the device, sense an output or reconfigure itself under electronic control or feedback.
MEMS History
The possibility of working at such small scales was foreshadowed by Richard Feynman in his famous 1959 talk “There’s Plenty of Room at the Bottom”. Feynman discussed the potential to manipulate and control things on a small scale, motivating the field of nanotechnology and eventually MEMS itself.
MEMS Applications
MEMS enable a wide variety of applications by integrating miniaturized sensors, actuators, and electronics:
- Microsensors for physical, chemical, and biological sensing
- Micromachines and microrobotics
- Microactuators for micro/nano assembly
- Micromanipulators like micro-mirrors
- Microfluidics with pumps and valves
Many of the integrated circuits in electronic devices today already incorporate MEMS components like accelerometers and gyroscopes found in smartphones.
MEMS Fabrication
MEMS are fabricated using processes derived from microelectronics manufacturing like deposition, lithography, and etching. But MEMS add additional mechanical fabrication steps to build moving parts and 3D structures.
The key advantages of MEMS are small size, low power consumption, and the ability to integrate sensing/control on a single chip via batch fabrication. However, MEMS face manufacturing challenges at very small scales.
Summary
In summary, MEMS enables the miniaturization of electromechanical devices down to the micrometer scale, unlocking new applications across multiple domains from consumer electronics to biomedical systems. The future of MEMS lies in continued miniaturization and integration of more functionality on-chip.