Semiconductor device and method of manufacturing the same

摘要

A first semiconductor pillar layer of a first conductivity type is formed on a main surface of a semiconductor substrate of the first conductivity type. A second semiconductor pillar layer of a second conductivity type is formed adjacent to the first semiconductor pillar layer. A third semiconductor pillar layer of the first conductivity type is formed adjacent to the second semiconductor pillar layer. A semiconductor base layer of the second conductivity type is formed on the main surface of the second semiconductor pillar layer. An insulated-gate type semiconductor element is formed in the semiconductor base layer. The carrier concentration on the side of a main surface of each of said first through third semiconductor pillar layers is higher than a carrier concentration on the opposite side of said main surface in each of said first through third semiconductor pillar layers.