High-voltage, large-area planar devices

By using basic elements of planar technology, a process and design for manufacturing 2-inch diameter rectifiers with up to 8.0 kV blocking voltage capability is presented. The diode structure used has a field plate overlay, a metallic equipotential ring (EQR), and a layer of resistive polycrystalline silicon film over the oxide and between the field plate and EQR electrodes. The results of this work offer new methods for fabricating power devices with higher blocking voltages than the traditional etched mesa devices.