Two device runs of high voltage bipolar 6H-SiC p(+)n diodes were fabricated. Emitter and HE (Junction Termination Extension) periphery were both realized by aluminum ion implantation, at room temperature (RT) for JTE, and both RT and 300degreesC for emitters. All diodes Current-Voltage characteristics were systematically measured in forward (0 --> 5V) and reverse bias (0 --> -50V). Breakdown voltages were also measured on a part of diodes. The emitter quality after implantation and annealing seems to be important for the diode behavior in forward and in reverse bias also. For the 300degreesC implanted diodes higher current densities (200 A.cm(-2) at 5V) are obtained in forward bias, with a more homogeneous distribution, showing better doping activation and layer quality. Compared to the RT implanted diodes, a less number of 300degreesC implanted diodes with high leakage currents is obtained. Those with the smallest emitter and the largest HE length sustain more than 1100V. The breakdown voltage value (V-BR) is similar to the calculated value and independent on the testing ambient. This indicates a breakdown in the bulk volume, confirmed by a lower V-BR for the RT implanted diodes. This lower V-BR value is due to the presence of an amorphous layer after implantation and thus residual defects at the emitter-epilayer junction interface.