The rationale is that in the contact surfaces of metals (e.g. lead) and semiconductor (n-type silicon wafers), the reverse voltage is blocked with the formed Schottky barrier. There is a fundamental difference between the rectifier and the principle of Schottky. Its pressure resistance is only about 40V. Its specialty is: Switching speed is very fast: reverse recovery time TRR particularly short. Therefore, the switching two poles and low voltage large current rectifier diodes can be made.