| 摘要 |
The invention provides a semiconductor having a transverse high-withstand voltage MOSFET which can be loaded together with a low-withstand voltage transistor, refined and is capable of adjusting the withstand voltage. The high-withstand voltage MOSFET comprises a trench portion (10) formed at the high-withstand voltage active region (4) on a semiconductor substrate (1); two poly-silicon layers (6) formed on the high-withstand voltage active region(4) on both sides of the trench portion (10) by implanting an impurity of the conductivity type opposite to the high-withstand voltage active region(4); two impurity diffusion drift layers (9) formed on both sides of the trench portion (10) by implanting an impurity of the conductivity type opposite to the high-withstand voltage active region (4) in the surface of the high-withstand voltage active region (4) under the poly-silicon layers (6); a gate electrode (13a) formed through a gate oxide film (11) on bottom and side surfaces of the trench portion (10) and end surfaces and upper surfaces of adjacent regions of the poly-silicon layers (6) close to the trench portion (10); and source and drain regions (15a) formed in the two poly-silicon layers (6) excluding the adjacent regions covered with the gate electrode (13a). |
