In order to meet the electrical and heat dissipation requirements between the chip and the base, ohmic contact should be achieved at both ends of the diode. Because the anode and cathode of fast soft recovery diode have complex structure and shallow diffusion depth, the traditional ohmic contact process of high power devices, sintering process, will destroy this structure and desired performance. The method to solve this problem is to adopt the ohmic contact process of multi-layer metals. Ohmic contact between anode and cathode is one of the difficulties and key points of this subject. On the basis of the existing theory and practice, the technological process is continuously improved to improve the performance and yield of the diode.