Analog Integrated Circuit Design, 2nd Edition

In this chapter, both the operation and modelling of semiconductor devices are described. Although it is possible to do simple integrated-circuit design with a basic knowledge of semiconductor device modelling, for state-of-theart design, an in-depth understanding of the second-order effects of device operation and their modelling is considered critical.

It is assumed that most readers have been introduced to transistors and their basic modelling in a previous course. Thus, fundamental semiconductor concepts are only briefly reviewed. Section 1.1 describes pn junctions (or diodes). This section is important in understanding the parasitic capacitances in many device models, such as junction capacitances. Section 1.2 covers the basics of MOS transistors and modelling. A summary of device models and important equations is presented in Section 1.3. This summary is particularly useful for a reader who already has a good background in transistor modelling, in which case the summary can be used to follow the notation used throughout the remainder of this book. Advanced MOS modelling is treated in Section 1.4, including behavior not covered by a simple square-law voltage–current relationship. It should be noted that all sections on MOS devices rely to some degree on the material previously presented in Section 1.1, in which depletion capacitance is covered. In addition, a brief description ...