High voltage 4H-SiC bipolar diodes have been realized using a 40 mum thick n-type epilayer, with a doping level at 1.1x10(15) cm(-3). These diodes have been designed with only one Junction Termination Extension as edge termination, whereas previous high voltage diodes described in literature are protected either by mesa either by a combination of JTE and mesa. Current voltage measurements show best breakdown voltage V-br at 4.8 kV when testing in Galden(R). After cutting the wafer into pieces (similar to5x5 mm(2)), V-br values seem to be reduced (similar to3.7 kV) and are in the same range both in Galden(R) and in SF6. In forward bias, the current density is found in the range of 100 A.cm(-2) at 5 V, but decreases rapidly when duration of bias increases.