Diamond Schottky barrier diode fabricated on high-crystalline quality misoriented heteroepitaxial (001) diamond substrate

We evaluated the performance of a diamond Schottky barrier diode (SBD) fabricated on a high-quality 7° off-axis heteroepitaxial (001) diamond substrate. The self-separated free-standing heteroepitaxial diamond substrate was grown on misoriented sapphire (α-Al2O3) with step-flow growth mode. It is Pseudo-vertical SBD with p + highly boron-doped epitaxial layer and 600 nm thin i-layer. The diamond SBDs showed high crystalline quality and excellent device performance. They exhibited a breakdown field strength of 2.1 MV·cm−1, which is the highest value ever reported for heteroepitaxial diamond SBDs. These results confirm the feasibility of realizing 2-inched wafer-scale diamonds in the field of power electronics.