Microelectromechanical Systems (MEMS), mechanical components, and electronic circuits combine to form miniature devices, typically tens of micrometers to hundreds of micrometers (millionths of a meter) in size, on a semiconductor chip. Typical applications for MEMS include sensors, actuators, and process control devices.
Interest in MEMS creation increased in the 1980s, but it took nearly 20 years to establish the design and manufacturing infrastructure needed for commercial development. One of the first products to have a large market was automobiles. كرابس An airbag controller that combines an inertial sensor to detect a collision and combines an electronic control circuit to deploy the airbag. Another early application of MEMS was inkjet printheads. After decades of research, in the late 1990s, a new type of electronic projector was marketed that used millions of micromirrors, each with its own electronic tilt control, to convert a digital signal into an image comparable to the best conventional TV displays. Emerging products include mirror arrays and integrated semiconductor chips for optical switching in telecommunications .Mechanical oscillators for radio frequency applications (eg cell phones) and a wide range of biochemical sensors for use in manufacturing, medical and security.
MEMS are fabricated using machining tools and materials used to manufacture integrated circuits (ICs). احتراف لعبة الطاولة 31
Usually a polycrystalline silicon layer is deposited with a so-called sacrificial layer of silicon dioxide .or any other material. The layers are patterned and etched before the sacrificial layer is dissolved to reveal three-dimensional structures including microscopic cantilevers, chambers, nozzles, wheels, gears, and mirrors. Significant economies of scale have been achieved by using many MEMS on a single silicon wafer to build these structures with the same batch processing methods used for IC manufacturing. Additionally, MEMS components are inherently “built in place”, unlike the manufacture of traditional mechanical devices, requiring no subsequent assembly.
The technical challenges of MEMS fabrication relate to the order in which electronic and mechanical components are fabricated. cabaretclub
High-temperature annealing is necessary to relieve stress and warpage in the polycrystalline silicon layer, but can damage the already added electronic circuitry. On the other hand, if you want to build mechanical parts, you first need to protect these parts while building electronic circuits. A variety of solutions have been used, including burying mechanical parts in shallow trenches before manufacturing the electronics and then exposing them later .
Barriers to further commercial penetration of MEMS include cost compared to simple technology costs, non-standardization of design and modeling tools, and the need for more reliable packaging. The current research focus is Nanometer dimensions (i.e., billionths of a meter) Nanoelectromechanical Systems (NEMS). At these scales, the vibrational frequencies of structures increase (from megahertz up to gigahertz frequencies), providing new design possibilities (such as noise filters). However, devices are becoming more and more susceptible to any defects that arise during the manufacturing process.