ABSTRACT
The process of constructing devices in a single piece of silicon crystal is a process of building successive layers of insulating, conducting and semiconducting material. Photolithography and etching procedures are used to achieve patterning of the layers for selective formation. The various methods for obtaining individual layers have their own usefulness for specific applications. The minimum feature size on each layer is determined by the ability to reproduce and resolve the feature routinely. This dimension is includes both the minimum dimension and how accurately that feature can be transferred into the silicon during the pattern transfer process. In early 1960’s Texas started the semiconductor manufacturing process and in 1963, Frank Wanlass got patent for CMOS technology. Since invention CMOS integrated circuits are fabricated by using the semiconductor device integrated fabrication process. The CMOS technology is used in development of the processors, micro controllers, embedded systems, digital logic circuits and application specific integrated circuits.
