What are NEOMS & MEMS?

NEOMS (Nano-Opto-Electro-Mechanical Systems) and MEMS (Micro-Electo-Mechanical Systems) uses mature integrated circuit fabrication technology to build devices that can combine microelectronics, sensors, and actuators into a single tiny package. The most common substrate for MEMS is silicon wafer and the fabrication techniques include wet isotropic/anisotropic etching, plasma etching, ion-implantation, dopant diffusion, thermal evaporation of thin films in vacuum, chemical vapor deposition, and molecular beam epitaxy. MEMS can be novel devices or existing devices that have been improved by making them:

Smaller – by using microlithography to pattern materials
Cheaper – via batch/production line processing
Reliable – through reproducible automated manufacturing of complex
devices that integrate many components on to a single chip.
Efficient – due to reduced power requirements and the close proximity of
interacting components.

What have people done with MEMS?

Accelerometers – Perhaps the most commercially successful MEMS device. They are used in air-bag systems. A tiny chip with a mass suspended on silicon springs can distinguish between the acceleration due to braking and that from collisions.

Micro-Mirrors – Texas Instruments pioneered these devices that contain arrays of 10-micrometer-wide silicon mirrors, pivoting on silicon hinges, which can be individually controlled in order to either block or reflect light. These are used in the projectors used for digital presentations. Other variations of micro-mirror devices are being used for optical switching. A new device by Xerox uses accelerometers to detect ambient vibrations and then implement corrections via mirror positioning so that ultra-high resolutions are achieved in laser printing. The Xerox device, including the laser and a rotating mirror that rasters the beam across the paper, fits in a regular TO-type can, commonly used for transistors.

Photonic Switches – A plethora of switching devices are being developed for optical communications. Some devices employ electrostatic (capacitor based) actuators to physically change the optical pathways.

Micro-Fluidics – Currently one of the hottest areas of nano-bio research. Tiny channels in silicon wafers can be used to deliver controlled amounts of drugs to precise locations in vivo, and also to direct fluids to sensors. Integrated glucose monitors / insulin dispensers have been made for diabetics.

Biomedical Implants – Silicon based cochlear implants that are inserted within the ear canal have been made. These devices contain sensors and processors that decompose audio waves into their Fourier components so they can be transmitted to the auditory nerve. Also, retinal implants that bestow partial vision to the totally blind are being developed. The market potential for MEMS in biomedical applications is huge.

Tiny Nano-Robots That Take Over the World – Sorry, this has already been done over a billion years ago by DNA. It is unlikely that humans will ever improve on Mother Nature’s creation; however, we can always look to her for inspiration.