In this chapter, ^[1] the operation and modeling of semiconductor devices are described. It is possible to do much digital integrated-circuit design with a relatively basic knowledge of semiconductor device modeling; for a first course in digital integrated circuits, the simplified modeling presented in Section 3.1 suffices assuming students have encountered MOS transistors in a previous course; other sections need be covered only as the need arises. For more advanced courses, or for those intending to design high-speed state-of-the-art circuits, more in-depth understanding of the second-order effects of device operation and their modeling is considered critical and the whole chapter might be studied.

Section 3.2 describes pn junctions (or diodes). This section is important in understanding the parasitic capacitances in many device models, such as junction capacitances. Section 3.3 covers MOS transistors and modeling. It should be noted that it relies to some degree on the previous material presented in Section 3.2, where depletion capacitance is covered. Section 3.5 covers bipolar-junction transistors and modeling. A summary of device models and important equations are presented in Section 3.11. This summary is particularly useful for a reader who already has a good background in transistor modeling in which case the summary can be used to follow the notation used throughout the remainder of this book. Finally, this chapter concludes with an Appendix in which the more physical-based device equations are derived and in which some subjects that are less relevant to digital integrated-circuit (IC) design, such as small-signal modeling, are...