THE EFFECT OF DOPING CONCENTRATION IN DETERMINATION OF CRITICAL ELECTRIC FIELD FOR BREAKDOWN IN Si VERSUS 4H-SiC

The critical electric field at breakdown is one of the most significant parameters in the design and performance of high power devices. In the present study the effect of doping concentration in determination of critical electric field for breakdown in Si versus 4H-SiC had been studied. The thesis focused on simulation study of how different doping concentration affects the critical electric field at breakdown and analytically calculating the critical field at electric breakdown in Si and 4H-SiC. The study compared the critical electric field at breakdown in Si with 4H-SiC for different doping concentration. The critical field for electric breakdown is one of the most significant parameters in the design and performance of high power devices. Python and origin software have been employed to collect data and to figure out the results. The result indicates when doping concentration increase, the critical electric field at breakdown in Si and 4H-SiC also increase and vice versa. For the same doping concentration, breakdown voltage in silicon carbide polytype (4H-SiC) is 56.2 times larger than in silicon, and the critical electric field in silicon carbide polytype (4H-SiC)is 8.2248 times larger than in silicon. Theoretically A relatively high breakdown voltage is the most distinguishing feature for a power device and in practical structures, the breakdown voltage can be drastically reduced by the enhancement of the electric field at the edges of the devices. So 4H-SiC power devices shows superior performance compared to Si because 4H-SiC have a magnitude higher breakdown electric field than Silicon.