Abstract: Because of its low bandgap and compatibility with Si process,SiGe material is widely used in high-frequency bipolar transistors.Here we exploit the same benefits of SiGe material in a new application area,namely ultra fast power diodes.We have produced discrete p+（SiGe）-n——n++ diodes.In addition to providing shorter reverse recovery time,lower forward voltage drop and peak reverse current compared with conventional Si diodes,the SiGe diodes have softer recovery characteristic.The reverse recovery time of SiGe diodes with 30 percentage Ge content are shorten by nearly three-quarter compared with Si diodes.The softness factor of Si diodes is far lower than one whereas that of SiGe diodes is close to one.Furthermore,the performance improvement doesn’t resort to lifetime killing technology therefore it can be easily integrated into power IC.