High Current Resistance Schottky Diode For High Frequency Switch Power Supply

High Current Resistance Schottky Diode For High Frequency Switch Power Supply​

MBR20100.pdf

The internal circuit structure of a typical Schottky rectifier is based on an N-type semiconductor substrate, on which an N-epitaxial layer with arsenic as a dopant is formed. The anode uses materials such as molybdenum or aluminum to make the barrier layer. Silicon dioxide (SiO2) is used to eliminate the electric field in the edge area and improve the withstand voltage value of the tube. The N-type substrate has a very small on-state resistance, and its doping concentration is 100% higher than that of the H-layer. An N+ cathode layer is formed under the substrate to reduce the contact resistance of the cathode. By adjusting the structural parameters, a Schottky barrier is formed between the N-type substrate and the anode metal, as shown in the figure. When a forward bias is applied to both ends of the Schottky barrier (the anode metal is connected to the positive pole of the power supply, and the N-type substrate is connected to the negative pole of the power supply), the Schottky barrier layer becomes narrower and its internal resistance becomes smaller; otherwise, if When a reverse bias is applied to both ends of the Schottky barrier, the Schottky barrier layer becomes wider and its internal resistance becomes larger.