SiO2/Si3N4passivation of high-power rectifiers

High-power mesa-type rectifiers were passivated with successive layers of SiO2and Si3N4by a low-temperature chemical vapor deposition technique. Reverse I-V characteristics, high-temperature yield, ancl blocking life test results are compared with values obtained with a polyimide coating. The high-temperature performance of the oxide-nitride passivated unit is found to be superior to the polyimide coated units. A strong correlation between the high-temperature leakage current and thermal stability of the device is noted.