A POWER FIELD EFFECT TRANSISTOR, A POWER FIELD EFFECT TRANSISTOR DEVICE AND A METHOD OF MANUFACTURING A POWER FIELD EFFECT TRANSISTOR

摘要

A power field effect transistor, a power field effect transistor device and a method of manufacturing a power field effect transistor are provided. During the manufacturing of the power field effect transistor, a body drive stage to manufacture the body region of the power field effect transistor is shortened to obtain a relatively low on resistance for the power field effect transistor. Before the implanting stage of the dopants of the body region, a pre body drive stage is introduced. During the pre body drive stage and the body drive stage sidewalls of a polysilicon layer of the power field effect transistor are oxidized to obtain a power field effect transistor which has at the sidewalls an oxidized polysilicon layer that is thick enough to prevent a premature current injection from the gate to the source regions of the power field effect transistor.

主权项

1. A method of manufacturing a power field effect transistor, the manufacturing method comprises the stages of:
obtaining a substrate of a first conductive type, the substrate having a first side, forming a patterned gate oxide layer on the first side of the substrate, the patterned gate oxide layer comprises a first opening, forming a patterned a polysilicon layer, the patterned polysilicon layer is at least formed on a portion of the patterned gate oxide layer , the patterned polysilicon layer having a side wall facing towards the first opening of the patterned gate oxide layer, providing a pre body drive stage during a first period of time longer than 20 minutes, forming a body region of a second conductivity type in the substrate, wherein the forming of the region of the second conductivity type comprises the stage of blanket implanting dopants of a second conductivity type into the substrate via the first opening in the patterned gate oxide layer and the stage of providing a body drive stage during a second period of time shorter than 45 minutes to obtain the body region that extends from the first side into the substrate below the first opening and partially below the patterned gate oxide layer, wherein in the pre body drive stage and the body drive stage a lateral oxidized polysilicon layer is formed at the side walls of the patterned polysilicon layer.