Semiconductor device and method for manufacturing the same

A semiconductor device comprising:

• a substrate comprising a cell region, a dummy region adjacent to the cell region, an upper surface and a lower surface opposite the upper surface in a first direction;
• an active pattern disposed on the upper surface of the substrate, the active pattern comprising a lower pattern extending in a second direction crossing the first direction and a plurality of sheet patterns spaced apart from each other in the first direction, the plurality of sheet patterns being disposed in the cell region;
• a plurality of gate structures spaced apart from each other in the second direction on the lower pattern, the plurality of gate structures comprising a gate electrode and a gate insulating layer, the gate electrode and the gate insulating layer surrounding the sheet patterns;
• a source/drain pattern disposed between the gate structures adjacent to each other;
• and
• a buried insulating pattern penetrating the substrate and the lower pattern in the dummy region,
• wherein the buried insulating pattern comprises a first surface and a second surface opposite to each other in the first direction,
• the first surface of the buried insulating pattern is on the same plane as the lower surface of the substrate, and
• the second surface of the buried insulating pattern is higher than the upper surface of the substrate.

A method for manufacturing a semiconductor device, comprising:

• providing a substrate comprising a cell region and a dummy region;
• forming a lower pattern on an upper surface of the substrate;
• forming an upper pattern comprising sacrificial patterns and active patterns alternately disposed on an upper surface of the lower pattern;
• forming a trench penetrating the lower pattern and the upper pattern;
• filling the trench with a field insulating layer;
• forming a mask pattern on the upper pattern;
• forming a buried insulating pattern penetrating the mask pattern, the upper pattern, and the lower pattern in the dummy region, a lower surface of the buried insulating pattern being lower than the upper surface of the substrate, and an upper surface of the buried insulating pattern and an upper surface of the upper pattern being disposed on the same plane;
• and
• recessing the buried insulating pattern to form a buried pattern up to the same plane as the upper surface of the lower pattern.