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Semiconductor materials

The vacuum tubes were widely used for various purposes in electronics, mostly voltage and power amplification, before the invention of solid state semiconductor devices in the 1940's. Since then semiconductor devices have gradually replaced vacuum tubes in most of such applications, due to many of their favorable properties such as small size, light weight, low energy consumption, high frequency capability, and high reliability. However, vacuum tubes can still find some applications even today, such as high power radio frequency transmitters and microwave ovens. Although the physics of vacuum tubes and semiconductor devices is very different, the basic functions are similar, such as controlling current through small voltage.

Additional notes on photodiodes, solar cells, and LEDs can be found here.

More detailed discussion about semiconductor physics can be found here


next up previous
Next: Diodes Up: ch4 Previous: ch4
Ruye Wang 2014-11-23