Intergrated Cicuits (IC) | ||||
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Thin Films |
Monolithic
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Thick Film | Hybrids | MEMS Silicon |
Bipolar
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Metal Oxide Semiconductor (MOS)
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Bi-CMOS
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MEMS is the itegration of mechanical elements, such as gears, sensors, actuators, and electronics standard silicon wafers using microfabrication tech. While the electronics are fabricated using integrated circuit (IC) process sequences (e.g. CMOS, Bipolar, BICMOS processes), the micromechanical components are fabricated using compatible "micromachining" processess that selectively etch away parts of the silicon wafer or add new structural layers to form the mechanical and electromechanical devices.
Microelectronic interated circuits can be thought of as the "brains" of a system and MEMS augments this decision-making capability with "eyes" and "arms" to allow microsystems to sense and control the environment. Sensors gather information from the envioronment thhrough measuring mechanical thermal biological chemical optical and decision making capabilitity direct the actuators to respond by moving, positioning, reglating, pumping, and filtering, thereby controlling the environment of some desired outcome or purpose. Because MEMS devices are manfactured using batch fabcrication techniques similar to those used for integrated circuits, unprecedented levels of functionality, reliability, and sophistication cn be placed on a small silicon chip at a relatively low cost
Micromachines are becoming more and more common in everyday life, An accelerometer is a good example of a micromachine which has made it's way into most of our daily lives. An accelerometer measures accelration and is the device used to detect an accident in automobiles. A processor will analyze the magnitutde of the acceleration and decide on whether or not to deploy the airbags in the vehicle. Many more examples exist which demonstate the feasibility and benefit of micromachines in the world today.
Your smart phone is loaded with MEMS devices. Below is just a summary of the devices and the associated wafers used to make them.
MOS devices have advantages over bipolar devices including lower power drain. MOS devices are also tinier than bipolar devices.