Ultralow Specific on-Resistance Trench MOSFET with a U-Shaped Extended Gate

【摘要】 An ultralow specific on-resistance(R_on,sp) trench metal-oxide-semiconductor field effect transistor（MOSFET）with an improved off-state breakdown voltage（BV） is proposed.It features a U-shaped gate around the drift region and an oxide trench inserted in the drift region（UG MOSFET）.In the on-state,the U-shaped gate induces a high density electron accumulation layer along its sidewall,which provides a low-resistance current path from the source to the drain,realizing an ultralow R_on,sp.The value of R_on,sp is almost independent of the drift doping concentration,and thus the UG MOSFET breaks through the contradiction relationship between R_on,sp and the off-state BV.Moreover,the oxide trench folds the drift region,enabling the UG MOSFET to support a high BV with a shortened cell pitch.The UG MOSFET achieves an R_on,sp of 2mΩ·cm² and an improved BV of 216 V,superior to the best existing state-of-the-art transistors at the same BV level.更多还原

【Abstract】 An ultralow specific on-resistance(R_on,sp) trench metal-oxide-semiconductor field effect transistor（MOSFET）with an improved off-state breakdown voltage（BV） is proposed.It features a U-shaped gate around the drift region and an oxide trench inserted in the drift region（UG MOSFET）.In the on-state,the U-shaped gate induces a high density electron accumulation layer along its sidewall,which provides a low-resistance current path from the source to the drain,realizing an ultralow R_on,sp.The value of R_on,sp is almost independent of the drift doping concentration,and thus the UG MOSFET breaks through the contradiction relationship between R_on,sp and the off-state BV.Moreover,the oxide trench folds the drift region,enabling the UG MOSFET to support a high BV with a shortened cell pitch.The UG MOSFET achieves an R_on,sp of 2mΩ·cm² and an improved BV of 216 V,superior to the best existing state-of-the-art transistors at the same BV level.更多还原