| 摘要 |
PROBLEM TO BE SOLVED: To provide a high-withstand-voltage MOS transistor having an element hardly broken even when a gate voltage in a saturated operation is high. SOLUTION: Metal wiring connected to a drain region is laid above a boundary portion between an oxide film formed by an LOCOS process or the like on a low-concentration impurity region of this N-channel type high-withstand-voltage MOS transistor and a high-concentration impurity region forming the drain region, thereby electric field concentration at the boundary portion which is a connection portion between the low-concentration impurity region and the high-concentration impurity region can be alleviated by an electric field generated from the metal wiring toward a semiconductor substrate, and breakdown of the element can be suppressed and the withstand voltage can be improved by suppressing impact ionization at a high gate voltage in the saturated operation of the NMOS transistor. COPYRIGHT: (C)2010,JPO&INPIT |
