Shallow angle implantation for extended trench gate power MOSFETs with super junction structure

In this paper, we present a new deep trench power MOSFET with super junction structure in the drift region, which exhibits strongly improved a relationship between blocking voltage and on-resistance. An accurate control of impurity concentration of n drift region in the trench sidewall is important to achieve the proposed MOSFET. Thus, we also quantitatively analyzed shallow angle ion implantations into trench sidewall by using a macrosize trench model. It was found that 40% ions doped into the incident sidewall and 12% ions were re-implanted into the opposite sidewall at the incident angle of 10 degrees.