Design And Process Simulation Of 50A/1200V MPS Diode

Power diodes are an important part of power semiconductor devices.Power diodes are found in almost all power electronics circuits.Switching devices have been rapidly developed in the past decades.In order to match the performance of switching devices,the new theory and new structure are needed to improve the contradictory relationship between conduction losses and switching frequencies in high voltage diodes.Merged PIN/Schottky Diode?MPS?diodes has the advantages of high blocking voltage,low forward conduction voltage,short reverse recovery time,and low reverse recovery peak current.Solve the contradiction between conduction loss and reverse recovery power loss.In order to fabricate MPS diodes with good performance,this paper first analyzes the working principle of MPS diodes,and analyzes the static characteristics and dynamic characteristics theoretically.Then using the Silvaco simulation software,a reasonable physical model was selected to simulate the characteristics of the MPS diode.On this basis,the 1200V MPS structural parameters were optimized and the trade-off characteristics of the device were simulated and analyzed.A good trade-off between forward conduction and reverse recovery characteristics was achieved.Compared with power PIN diodes,MPS diodes have better characteristics without life-time control.Third,the terminal structure of the power device was designed and the terminal structure of the MPS diode was determined.Fourth,the process design and process conditions of the designed device structure are simulated.The specific process is determined,and the layout and cell number required for manufacturing the device are designed.Finally,the device structure parameters were selected:the doping concentration of N-drift region was 7.6×10¹³cm^-3,the thickness was 173?m,the carrier lifetime of drift region was 2us,the peak concentration of P+surface was 5×10¹⁸cm^-3,and the junction depth was 6?m.The N+surface peak doping concentration was 1×10¹⁹ cm^-3 and the thickness was41?m.The cell PIN region size was 20?m;the barrier height of the Schottky region was 0.8eV.The area ratio of the Schottky area is 33%,50%,and 60%,respectively.The performance parameters are as follows:test conditions are 27?,I_F=50A,d Idt=200A?s,V_R=600V,reverse recovery stored charge are 12.33?C,10.60?C,9.82?C,reverse recovery time is 600ns,570ns,550ns,softness factors are 1.59,1.60,1.62;The forward voltage drops are 1.52V,1.61V,and 1.67V;at 127?,the reverse leakage currents are 1.40mA,1.45mA,and 1.50mA.This paper has completed the design of the 50A/1200V MPS diode and confirmed the process,providing a reference idea and method for the design and manufacture of the MPS diode in the future.