A Novel Power MOSFET Structure with Shallow Junction Dual Well Design

Abstract

Vertical Power MOSFETs are widely designed by deep structures for breakdown requirement. In this study, we proposed, simulated, and analyzed a dual well structure Power MOSFET, which utilize an n-well to cover the conventional p-well. The cell pitch can be reduced and results in an increased cell density. The reduced cell pitch and increased cell density improves the gate charge and on resistance performances about 66.5% and 15.8% without sacrificing the device breakdown owing to a shallow junction design. In addition, with the dual structure design, the breakdown point will occur at the center of the well. Therefore, the capability of avalanche energy can be improved about 1.9 times than the tradition structure.