The MOS Transistor

In this chapter we shall deal with those physical and device modelling issues that constitute the foundations of analogue integrated circuit design. We shall start with a resume of the basic principles of solid state physics. Following this, we shall discuss the most important properties of the basic materials used in microelectronics. The fabrication steps of a typical CMOS process will also be considered. Subsequently, we shall analyse the modelling of MOS transistors, both at a simplified level, appropriate for hand calculations, and at a more complex level, suitable for computer simulation. In the last part of the chapter, we shall study noise performance and, finally, we shall discuss layout techniques suitable for analogue applications. The subjects considered in this chapter form the basis for the following chapters; knowledge of these conceptsis a key element in any successful analogue design.