Huixin gives a brief introduction of Schottky Barrier Diode

　　Schottky Barrier Diode, an ultra fast semiconductor device with low consumption and large current, is created in recent years. Its reverse recovery time could be as short as several NS and its forward conductivity voltage drop is only 0.4V while the rectifying current could reach to several thousand Amp. The above advantages are the reasons why Schottky Barrier Diode could exceed Fast Recovery Diode.

　　Basic theory of Schottky Barrier Diode( SBD for short ): use the shaped Schottky to block the reverse voltage on the touching area between metal, for example, Lead, and semiconductor ( N silicon ). There is a fundamental difference between Schottky and the rectifying function of PN junction. The degree of withstanding voltage of Schottky is only 40V. The advantages of Schottky include particularly fast switching time and short reverse recovery time. Hence, it can be used to make switching diode and rectifier diode of low voltage and large current.

　　Schottky Barrier Diode is a type of “metal-semiconductor junction” diode that has the feature of Schottky. It has low starting forward voltage and its Tungsten plating could be replaced by Gold, Molybdenum, Nickel and Titanium. The gadget conducts by the major carriers, which means that its reverse current is much larger than the PN junction with minor carriers. Due to the poor storage effect of those minor carriers, the frequency is usually restrained by the RC time. Hence, SBD, with a maximum working frequency of 100GHz, is an ideal component for the high frequency and fast switching electronic products. Moreover, MIS ( Metal-Insulatior-Semiconductor ) could be used to produce solar battery and LED.

　　Schottky Barrier Diode delivers charges by only a kind of carrier which is known as electron. Owing to no left carriers outside the barrier, there is no such issue as charge storing and that actually improves the speed of switching. Besides, the reverse recovery time has shorten to within 10ns. However, the degree of withstanding reverse voltage is below 100V. Therefore, Schottky Barrier Diode is suited for low voltage and large current circumstance and by using its feature of low voltage drop, the efficiency of rectifying or freewheeling circuit could be improved.

　　To sum up, there exist big differences on inner structure between Schottky Barrier Diode and PN junction. Recent years Silicon Planar Schottky Barrier Diode was created. It not only saves the expensive metal and reduces the cost, but also alters the coherence of parameter.