Prof.Dr.L.SUJATHA, HOD/ECE, Rajalakshmi Engg College on 29.01.13.

One of the most exciting technological developments during the last decade of the 20th century was the field of microelectromechanical systems (MEMS). MEMS consist of micro fabricated mechanical and electrical structures working in concert for perception and control of the local environment. It was no accident that the development of MEMS accelerated rapidly during the 1990s, as the field was able to take advantage of innovations created during the integrated circuit revolution of the 1960s to the 1980s, in terms of processes, equipment and materials. A well-rounded understanding of MEMS requires a mature knowledge of the materials used to construct the devices, as the material properties of each component can influence device performance. Because the fabrication of MEMS structures often depends on the use of structural, sacrificial and masking materials on a common substrate, issues related to etch selectivity, adhesion, microstructure and a host of other properties are important design considerations. A discussion of the materials used in MEMS is really a discussion of the material systems used in MEMS, as the fabrication technologies rarely utilize a single material, but rather a collection of materials, each providing a critical function.