... early electronic years, the majority of microcircuits were realized using bipolar- junction transistors (BJTs). However, in the late 1970s, microcircuits that used MOS 24 Chapter 1 Integrated-Circuit ... again, Lo, is usually empirically derived. Two other capacitors are often important in integrated circuits. These are the source and drain sidewall capacitances, C,,, and Cd-sw. These capacitances ... drain-bulk capacitances are significant compared to the gate-source capacitance. Thus, for high-speed circuits, it is important to keep the areas and perimeters of drain and source junctions as small...