The planar edge termination technique with oxide ramp at the periphery of the contact is extended to SiC Ti, Pt and Ni Schottky and pn junction diodes. We have fabricated high voltage 4H-SiC diodes to verify the efficiency of this termination. In addition, we extended the study to the UV detection performances of specifically design Schottky and junction barrier diodes with oxide ramp termination by numerical MEDICI simulation.