A first trench is formed in a surface of an n.sup.+ -type semiconductor
substrate that forms a source region. A p-type base region, an n.sup.-
-type drift region, and an n.sup.+ -type drain region are deposited in
this order in the first trench using epitaxial growth. A second trench
extending from the source region to the drift region through the base
region is formed in the surface. A gate insulating film and a gate
electrode are formed on a surface defining the second trench. The n.sup.+
-type drain region has a location where growing surfaces come together in
epitaxial growth and where a defect is likely to occur, and the gate
electrode lacks such a location and thus avoids an increase in normalized
ON resistance. Therefore, the breakdown voltage remains high without
increasing the ON resistance.