半导体材料特性.ppt

自由電子流在n型矽 自由電子往正端流 電源供應的正端 電子流 電源供應的負端 圖 2.24 受體電子提供一個電子空位，形成p型矽 電洞 硼原子當作p型的摻質 Si Si Si Si Si Si Si Si Si Si Si Si Si Si Si Si B Si Si Si Si Si Si B B 摻雜硼以形成p型矽 圖 2.25 在p型矽的電洞流 電子流 電洞流 電源供應的正端 電源供應的負端 電洞往負端流 電子往正端流 圖 2.26 矽的電阻率與摻質濃度之關係 Redrawn from VLSI Fabrication Principles, Silicon and Gallium Arsenide, John Wiley Sons, Inc. 電阻率 (?-cm) 1021 1020 1019 1018 1017 1016 1015 1014 1013 10-3 10-2 10-1 100 101 102 103 n-型 p-型 圖 2.27 摻質濃度 (atoms/cm3) p-型矽 n-型矽 pn接面橫切面 圖 2.28 其他半導體材料 表 2.3 * This basic circuit illustrates the principle of copper wires being used to create conductive paths for free electrons. The negative (-) pole of the battery repels the electrons inside the copper wire, while the positive (+) pole attracts the electrons. The lamp in the circuit creates light due to the friction of the electrons passing through the tungsten filament (not as good a conductor as copper). The friction is so intense that it generates temperatures high enough to cause the filament to glow. * The salt dissociates into its basic elements of sodium (Na+) and chlorine (Cl-). The two elements become ions, or charged atoms. The net effect of these charges in the water is the same as having free electrons in a piece of copper wire. If there are enough ions in the water, these may provide the complete circuit needed to sustain current flow inside the water. * The capacitor is one of the simplest electronic components used in nearly every electronic product. The purpose of the capacitor is to store an electrical charge and to transfer electrical data from one place to another with the aid of an electrical field. The basic capacitor consists of two conductors separated by an insulator (dielectric material) such as glass, mylar or even air. Wires serve as the connections to other components that the capacitor is to be joined to. * We’ll use this simple circuit to explain how a capacitor can hold an electrical charge. In this circuit a 1.5 Volt flash