Patent ID: 7317225

Claim:
A power semiconductor device comprising: a drain layer of a first conductive type; first pillar layers of the first conductive type and second pillar layers of a second conductive type which constitute a super-junction structure on said drain layer of a device section and which arranged alternately in a horizontal direction, each of said first and second pillar layers having a column-shaped sectional structure; base layers of the second conductive type which are formed on surface portions of said second pillar layers; source layers of the first conductive type formed on a surface portion of said base layers; gate electrodes, each formed through a gate insulating film over a region from one of said source layers formed on the surface portion of one of said base layer to the other of said source layers formed on the surface portion of the other of said base layer adjacent to the one of said base via one of said first pillar layers; third pillar layers of the first conductive type and fourth pillar layers of the second conductive type which are adjacent to the super-junction structure of the device section to constitute another super-junction structure thinner in a vertical direction than the super-junction structure of the device section on said drain layer of a device termination section and which are arranged alternately in a horizontal direction, each of said third and fourth pillar layers having a column-shaped sectional structure; an outermost pillar layer which is stacked on one of said third or fourth pillar layers in the super-junction structure of the device termination section nearest to the device section to be additionally formed to an outermost portion of the super-junction structure of the device section nearest to the device termination section and which has an impurity concentration less than that of each of said first and second pillar layers; a high resistance layer of the first conductive type which is formed on said third pillar layers and said fourth pillar layers and has a resistance value higher than that of each of said first and second pillar layers and said base layers; a source electrode which is formed to be electrically connected with said base layers and said source layers; and a drain electrode which is formed on a back face of said drain layer.