The Design And Fabrication Of10A/300V、400V JBS Diode

The low forward voltage drop and fast switching speed make the Schottky diodes especially suitable for high speed switching circuit and high current output circuit. However, its low breakdown voltage and large leakage current limit its application scope.The Junction Barrier Controlled Schottky diode (JBS) combines the Schottky barrier and pn junction barrier, who owns lower forward voltage drop, larger current density than p-n junction diode and higher breakdown voltage, lower leakage current than Schottky diode, which are the advantages Schottky diode and p-n junction diode. In view of the highest breakdown voltage of Schottky diode on the market is about200V, the main purpose of this paper is to design and fabricate a new kind of JBS diode with forward current larger than10A, breakdown voltage above300V and400V.The Schottky junction boundary in Schottky junction devices causes the concentration of the electric field due to the bend of boundary depletion layer when the reverse bias is applied. And thus the electric field becomes large which leads breakdown at low voltage of the Schottky divices (200V or less). For higher breakdown voltage, two Field Limiting Rings (FLR) and a Cut Ring is used as terminal structure coupled with JBS structure in this paper. This paper analyzes and computes several FLR model, then use the best model to calculate the corresponding parameters. And then the mask is made.This paper designed a circular Schottky barrier JBS and a circular p-n junction barrier JBS. To fabricate JBS diode with forward current larger than10A, breakdown voltage above300V and400V, we adjust its junction depth and the concentration of the epitaxial layer during the progress. The design and final test are done by Lanzhou university, the fabrication and middle test are done in Tianshui daylight Semiconductor Co.,ltd, when completed, the JBS diodes are delivered to Tianshui huatian Electronics Group for package.This work is supported by Gansu province Science and Technology Support Project(090GKCA049):"the development of5A-10A/200V、300V、400V power Schottky diode series".