Extreme dielectric strength in boron doped homoepitaxial diamond

The fabrication of Schottky diodes withstanding breakdown voltages up to 10 kV is demonstrated. A corresponding electric field of 7.7 MV/cm at the center of the diode is evaluated with the help of a two-dimensional finite elements software. These properties result from a net shallow acceptor concentration below 1016 cm−3 in the first micrometers of an epitaxial film with optimized crystalline quality and a special oxidizing treatment of its surface, allowing the true dielectric strength of bulk diamond to be revealed.