Micromachining Techniques / Processes

A Microsystem is an intelligent miniaturized system comprising sensing, processing and actuating functions. A micro engineering refers to the technologies and practice of making three dimensional structure and devices with dimensioned in the order of micrometers. Micromachining is a basic technology used for the production of miniaturized parts and components. Micromachining resulted in the fabrication of a broad class of devices whose defining characteristics were micrometer scale feature size and electromechanical functionally, and these systems are collectively called as MEMs (Micro-Electro Mechanical Systems). Micro Electro Mechanical Systems, or MEMS, are micron-sized machines that can be used as mechanical, electrical, or chemical transducers. Many different fields such as the automotive and medical industries utilize MEMS because of four advantages 1) easier to mass-produce, 2) lower cost of production, 3) easier to make part alterations, and 4) higher reliability compared to large-scale machines. MEMS are generally made of Polycrystalline Silicon, which is the same material used to make integrated circuits (IC). To manufacture MEMS devices, a process called photolithography is used. The general steps of the two-mask photolithography process are discussed. We can produce many type of MEMS devices using photolithography. One of the most notable applications of MEMS devices is the accelerometer (crash sensor) of the airbag deployment system in modern automobiles. MEMS crash sensor will replace the less capable large-scale device for a fraction of the cost. MEMS development has just begun and researchers as well as engineers are working hard to create more and better MEMS devices to serve us in the future.