High-voltage (>2.5kV) 4H-SiC Schottky rectifiers processed on hot-wall CVD and high-temperature CVD layers

High-voltage Ni/4H-SiC Schottky rectifiers have been fabricated on thick low-doped epilayers grown by hot-wall chemical vapor deposition (CVD) or high-temperature CVD (HTCVD). A metal overlap onto an oxide layer was employed to reduce electric field crowding at the contact periphery. By utilizing a 42 mu m-thick epilayer doped to 1 similar to 2x10(15)cm(-3), a record blacking voltage of 3.0kV was achieved. The reverse leakage current was very low, 7x10(-7)A/cm(2) at -1.0kV (2.8kV diode). Specific on-resistance was 34m Omega cm(2) for a 3.0kV diode. A high breakdown voltage of 2.6kV was also attained for a diode processed on an HTCVD layer.