Method for manufacturing semiconductor device having super junction construction

A method for manufacturing a semiconductor device, comprising the steps of:

• forming a plurality of second parts having a second conductive type, wherein each second part is disposed separately;
• forming a plurality of first parts having a first conductive type, wherein each first part is disposed between the second parts so that a drift region including the first and second parts aligned alternately in a repeat direction is provided;
• forming a body region having the first conductive type on the drift region;
• forming a trench, which penetrates the body region and reaches the drift region, wherein the trench extends in parallel to the repeat direction;
• forming an insulation film on an inner wall of the trench;
• and embedding a gate electrode in the trench through the insulation film.

A method for manufacturing a semiconductor device, comprising the steps of:

• forming a plurality of second parts having a second conductive type,
• wherein each second part is disposed separately;
• forming a plurality of first parts having a first conductive type,
• wherein each first part is disposed between the second parts so that an under drift region including the first and second parts aligned alternately in a repeat direction is provided;
• forming a semiconductor layer on the under drift region,
• wherein the semiconductor layer has the first conductive type and an impurity concentration of the semiconductor layer is equal to or lower than that of the first part of the under drift region;
• and
• doping an impurity having the second conductive type into a part of the semiconductor layer so that the part of the semiconductor layer changes its conductive type from the first conductive type to the second conductive type, wherein the part of the semiconductor layer is disposed on the second part.