文档介绍：二极管和三极管
广东工业大学物理与光电工程学院
Diode and Transistor
The P-N Junction (or Diode)
When a free electron meets a moving hole in a semiconductor material, the electron occupies the free space and a positive or negative charge no longer exists; that is, the charge is neutralized. When a P-type and a N-type crystal are joined to make a single semiconductor, as shown in Figure, current will flow in one direction only.
二极管和三极管
P-N节(或二极管)
在半导体材料中,当一个自由电子碰到空穴时,电子将占据空位,这个时候正电荷或者是负电荷将消失;也就是说,电荷被中和掉了。当一个p型和n型被连接成一个单独的半导体时,如图所示,电流将只朝一个方向流动。
When a power source is connected to the semiconductor as shown in Figure, the semiconductor is said to be forward biased.
At the junction, the bine with the hole. Electrons enter the semiconductor at the N terminal to replace the electrons that bined with the holes. Likewise, electrons leave the P terminal by attraction of positive voltage and create new holes. This movement of electrons, from the negative voltage source through the junction and from the positive terminal of semiconductor to positive voltage source, creates a current flow. Thus current will flow in a semiconductor when the semiconductor is forward biased.
如图所示,当一个电源连接到半导体,半导体会产生正向偏压。
在PN节,电子和空穴结合。外电场将多数载流子推向空间电荷区使其变窄。由于电源的作用,当PN节正向偏压,扩散运动源源不断的进行,从而形成正向电流,PN节导通。
When the polarity of the power source is reversed, the semiconductor is said to be reverse biased. In practical terms, there will