| 摘要 |
<p>A semiconductor device including a high-withstand voltage and a manufacturing method thereof are provided to suppress a short channel effect by using a portion doped with impurity ion which serves as a channel stopper. A MOSFET formed in a high-withstand voltage active region of at least one section of an active region has a trench portion(10) formed in the high-withstand voltage active region of a first conductivity type. Two polysilicon layers are formed on the high-withstand voltage active region by implanting an impurity of a second conductivity type opposite to the first conductivity type. Two impurity diffusion drift layers are positioned on both sides of the trench portion, and are formed by implanting an impurity of the second conductivity in a surface of the high-withstand voltage active region. Gate electrodes(13a,13b) are formed on bottom and side surfaces of the trench portion. A source region(15a) and a drain region(15b) are formed in the two polysilicon layers that are not covered with the gate electrode.</p> |
