POWER SEMICONDUCTOR DEVICE HAVING FIELD PLATE STRUCTURE

摘要

PURPOSE: A power semiconductor device with a field plate structure is provided to implement a stable breakdown voltage property by suppressing the deterioration of a breakdown voltage even though charges are changed on an interface between a semiconductor substrate and an oxide layer. CONSTITUTION: A plurality of field limiting rings(121) are formed on one side of a semiconductor substrate. An interlayer dielectric layer(108) is formed on the upper side of the field limiting ring. A plurality of field plates(122) are formed on the upper side of the interlayer dielectric layer. In comparison with a bonding boundary side of an active region side of the corresponding field limiting ring, the end of an active region side of each field plate is closer to the active region to reduce the change of a breakdown voltage due to the change of an interfacial charge. [Reference numerals] (AA,BB) End region direction; (CC,DD) Active region direction; (EE) Formation end of a field plate; (FF) Formation end of a field limiting ring;