Influence of carrier lifetime control process in superjunction MOSFET characteristics

This paper reports device characteristics of superjunction (SJ) MOSFETs employed with platinum (Pt) doping or electron irradiation processes for high speed recovery operation of the internal body diode. For the inverter application, high speed recovery operation of the internal body diode is necessary. 600 V-class SJ-MOSFETs were fabricated with a lifetime control process. In this paper, the influence of the carrier lifetime control process upon the on-resistance, leakage current and withstanding capability are reported. The lifetime control process modulates the static characteristics, and it is difficult to obtain the high speed operation with t
rr
< 100 ns maintaining both low on-resistance and low leakage current. However, the withstanding capability is not problematic due to suppressing the carrier concentration by the short lifetime.