Field plate configuration of a semiconductor device

Abstract(summary):

A semiconductor device includes a semiconductor substrate having a principal surface, and an insulating film formed on the principal surface and continuously covering a top surface of a first boundary region and a top surface of a second boundary region, the first boundary region including a boundary between a well layer and a RESURF layer, the second boundary region including a boundary between the RESURF layer and a first impurity region. The semiconductor device further includes a plurality of lower field plates formed in the insulating film in such a manner that the plurality of lower field plates do not lie directly above the first and second boundary regions, and a plurality of upper field plates formed on the insulating film in such a manner that the plurality of upper field plates do not lie directly above the first and second boundary regions.