Interfacial damage extraction method for SiC power MOSFETs based on C-V characteristics

In this work, a useful interfacial damage extraction method for SiC power MOSFETs based on the C-V characteristics is proposed. According to the five different interface situations of the channel region and the JFET region, the Cg-Vg curve can be divided into five relatively independent parts. It demonstrates that the charges injected into the oxide of channel region will lead to an opposite shift in part 11 while the charges injected into the JFET region will result in the shifts in part 111 and IV. Through this way, the location of the charges injected in to the SiO2/SiC interface can be distinguished. The correctness of the method is proved by a UIS-stressed SiC power MOSFET. Moreover, the density of the charges injected into the interface oxide can be calculated by the amplitude of the shift in the Cg-Vg characteristic.