Optimization of Body Diode Reverse Recovery Characteristics of Lateral Power MOSFETs for Synchronous Rectifier DC-DC Converters

An Analysis of the Switching Performance and Robustness of Power MOSFETs Body Diodes: A Technology Evaluation

“…It has been previously shown that the body diode can be actually be a suitable replacement for the PiN diodes when it comes to soft switching converters such as ZVS [11]- [15]; however, the use of the body diode may create a significant robustness issue when it comes to hard commutation switching [16]- [18]. To overcome this, different MOSFET designs were tested including lateral Power MOSFET [19], [20], VDMOSFT [21], VMOS, LDMOS, TrenchMOS [22], UMOS [23], semi-super-junction [24] and eventually super-junction MOSFETs [25], [26] or CoolMOS [27] all of which although showed certain improvements, but could not help the overall poor reverse recovery performance of the body diodes during hard commutation. Though certain efforts were made to use methods such as active channel freewheeling [28] to minimize the effect of the recovery charge, the performance of the body diode during the reverse recovery could not be improved.…”

A laser annealing process for high-performance power MOSFETs

“…In other words, the impurity distribution profile in the shallow junction is very close to the ideal step junction. It expected that this shallow junction will lead a fast reverse recover characteristics in the body diode of U-MOSFET [9]. The proposed laser annealing process is very promising for next generation power MOSFET fabrication.…”