MEMS stands for Micro-Electro-Mechanical Systems and if that makes no sense to you, don’t worry—lots of people are just discovering this new technology for themselves.
This unique system combines sensors, actuators, mechanical components, and electronics on one silicon base; essentially it is a type of glorified computer chip.
Typically, microfabrication is used to apply the various elements to their silicon wafer.
The many components that go on the wafer all have their different manufacturing processes: electronics are typically made separately using integrated circuit, or IC, process sequences (this can include BICMOS, CMOS, or Bipolar techniques.) The micromechanical elements, on the other hand, are often micromachined.
This means that a high-tech device, sometimes a laser cutter, etches away parts of the silicon chip, or sometimes areas are added in order to create the end result.With the advent of MEMS technology, the techno-geek dream of having an entire system on one chip has become reality.
Prior to MEMS, two separate components were required to work in tandem: the microelectronics on a silicon chip, and the micromachined mechanical elements in a different format. Combining them into one efficient MEMS system eliminates several steps of production as well as the need for a connector between the two elements.
This allows for the development of “smart” products because microelectronics can perform delicate computational functions which are then enacted by the fine-tuned physical accuracy of microsensors and microactuators. Smart MEMS products with these kinds of capabilities open up a whole new world of applications and technological design possibilities.
Understanding what the different parts of a MEMS chip are all about becomes easy when you think of the microelectronic integrated circuits as the brains of the operation, sending signals to the microsystems that will then act as eyes, arms, legs, etc. to carry out the desired action.
Once the microsensors have received the circuits’ directions they sense their environment, measuring different factors such as thermal readings, biological presence, mechanical functions, chemicals, optical information, and magnetics—this information is then relayed back to the “brain” for more decision-making, and all of these steps take place in a matter of seconds.
The fact that MEMS microchips can to some degree make their own decisions fits in with other innovations in the field of nanotechnology; nanotech scientists have always made it plain that they are working toward an ideal autonomous product (which will perhaps reach its peak expression in the nanorobot, but is nevertheless an integral part of most nanotechnology products.)
Decision-making capabilities as well as sensors that allow the MEMS chip to detect its environment are key factors in its superior functioning. The actuators usually perform functions like physically moving their entity, positioning in small increments, regulating data, pumping fluids or air, and filtering various substances.
Typically the functions associated with a device that uses MEMS technology are somehow related to controlling the surrounding environment in order to achieve a desired outcome. Before MEMS technology other devices were capable of doing similar tasks, but to date none has been as efficient as MEMS.
This is because MEMS chips can typically be made using batch fabrication manufacturing in much the same way that integrated circuits are produced, which renders them extremely low in cost as well as more functional, more reliable, and also more sophisticated. And perhaps the best part is that all of these superior features can be combined onto one small silicon chip.
Almost every industry can benefit from having such fine-tuned technology at their disposal. The dual nature of MEMS systems allow them to bridge gaps between previously unassociated subjects, such as microelectronics and biology, for example.
Biotechnology has benefited from MEMS developments like the Polymerase Chain Reaction microsystems which can be used to amplify and identify DNA. MEMS has also given rise to Scanning Tunneling Microscopes, which are made with the micromachining process; biochips that have the ability to scan and detect chemical and biological agents which may be hazardous; and microsystems that render drug screening and selection more effective.
In the communications field, high frequency circuits have been upgraded with MEMS technology so that they can perform better and more cost-efficiently. Electrical elements of these circuits tend to benefit the most, such as their tunable capacitors and their inductors—and best of all, production and installation become a simplified process because no integration is required when MEMS is used.
The mechanical switches used to run these systems also show large improvements when upgraded with MEMS. The only drawback for MEMS communications devices lies in their reliability and packaging; in some cases the same product has had consistency issues across the board and resolving these problems will prompt greater acceptance in the marketplace.
Accelerometers are used for a variety of scientific applications, and MEMS can improve these functions too. MEMS accelerometers are quickly rendering their conventional counterparts obsolete, especially when it comes to airbag deployment in automobiles.
MEMS accelerometers can sense not only the fact that an impact has occurred, but they can also judge the speed, intensity, and several other crash-related factors in order to determine the rate at which an airbag system should deploy and also how much of the airbag to release.
This has the potential to save lives, since too much or too little airbag has often resulted in crash deaths. The traditional accelerometer is actually a series of devices integrated together at various points throughout the vehicle, with their attendant electronics positioned near the airbag.
This system is not only clunky and awkward, but allows the system parts to become cut off from each other at several points, possibly resulting in complete lack of accuracy or even a total system malfunction.
This conventional accelerometer package typically costs about $50 per vehicle. MEMS nanotech accelerometers, on the other hand, can integrate all the fundamental parts onto one small silicon chip. Such an approach renders them lighter, more accurate, and less expensive—MEMS accelerometers tend to average about $5 or $10 per vehicle, saving the consumer money many times over.