Semiconductor device with high breakdown voltage

摘要

A technique is provided which allows easy achievement of a semiconductor device with desired breakdown voltage. In a high-potential island region defined by a p impurity region, an n⁺ impurity region is formed in an n^- semiconductor layer, and first field plates and second field plates are formed in multiple layers above the n^- semiconductor layer between the n⁺ impurity region and the p impurity region. The second field plates in the upper layer are located above spaces between the first field plates in the lower layer, over which an interconnect line passes. One of the second field plates which is closest to the p impurity region has a cut portion under the interconnect line, and an electrode is spaced between the first field plates located under the cut portion.