A bipolar diode is provided having a drift layer of a first conductivity type on a cathode side and an anode layer of a second conductivity type on an anode side. The anode layer includes a diffused anode contact layer and a double diffused anode buffer layer. The anode contact layer is arranged up to a depth of at most 5 μm, and the anode buffer layer is arranged up to a depth of 18 to 25 μm. The anode buffer layer has a doping concentration between 8.0*1015 and 2.0*1016 cm−3 in a depth of 5 μm and between 1.0*1014 up to 5.0*1014 cm−3 in a depth of 15 μm (Split C and D), resulting in good softness of the device and low leakage current. Split A and B show anode layer doping concentrations of known diodes, which have either over all depths lower doping concentrations resulting in high leakage current or enhanced doping concentration resulting in bad softness.