What is a Schottky diode?
Schottky diode, English is Schottky diode, is a kind of diode: its on voltage drop is very low and allows high-speed switching. As an electronic component, it is produced by using the characteristics of Schottky barrier.
The reason why it is called "Schottky" diode is to commemorate the car physicist Walter h. Schottky.
As mentioned above, the on voltage of the Schottky diode is very low. The voltage drop of Schottky diode is only 0.15-0.45 V compared with the voltage drop of about 0.7-1.7 V generated by the general diode when the current flows. Therefore, using Schottky diodes can improve the efficiency of the system.
Structure of Schottky diode
The Schottky diode uses the metal semiconductor interface as the Schottky barrier to generate rectification effect, which is different from the p-n junction generated by the semiconductor semiconductor interface in general diodes.
Based on the characteristics of Schottky barrier, the on voltage drop of Schottky diode is very low, and the switching speed can be improved.
Disadvantages of Schottky diode
The biggest disadvantage of Schottky diode is that its reverse bias is relatively low and the reverse leakage current is too large.
For Schottky diodes using silicon and metal as materials, the maximum reverse bias rated withstand voltage is only 50V (nowadays, due to technological progress, the maximum voltage can reach 200V), and the reverse leakage current is a positive temperature characteristic, which is easy to rapidly increase with the temperature rise. Attention should be paid to the hidden danger of thermal breakdown.
In order to avoid the problems caused by the above disadvantages, the reverse bias of the Schottky diode will be much smaller than the rated value in actual use.
The current technology can also produce Schottky diodes with higher reverse bias voltage, but the on voltage will also rise to the same level as that of ordinary diodes. Therefore, this kind of diode has no advantages in applications except where high switching speed is required.
