Semiconductor device

A semiconductor device comprising:

• a substrate having an active region;
• at least one nano-sheet stack structure spaced apart from an upper surface of the active region and facing the upper surface of the active region, the at least one nano-sheet stack structure including a plurality of nano-sheets each having a channel region;
• a gate extending on the active region to cross the active region and covering the at least one nano-sheet stack structure, wherein the gate comprises a main gate portion on the at least one nano-sheet stack structure and a sub-gate portion disposed below each of the plurality of nano-sheets;
• a gate insulating layer between the at least one nano-sheet stack structure and the gate;
• a source/drain region on the active region on both sides of the at least one nano-sheet stack structure;
• an outer spacer on the plurality of nano-sheets and covering a sidewall of the main gate portion;
• inner spacers between the source/drain region and the gate, and between the plurality of nano-sheets;
• and
• a source/drain protection layer on a sidewall of the at least one nano-sheet stack structure and between the source/drain region and the at least one nano-sheet stack structure.

A semiconductor device comprising:

• a fin-type active region protruding from a substrate and extending in a first direction;
• a plurality of nano-sheets that are spaced apart from an upper surface of the fin-type active region and spaced apart from one another in parallel to the upper surface of the fin-type active region, each of the plurality of nano-sheets having a channel region;
• a gate extending on the fin-type active region in a second direction crossing the first direction and surrounding at least a portion of each of the plurality of nano-sheets, wherein the gate comprises a main gate portion on at least one nano-sheet and a plurality of sub-gate portions disposed between the nano-sheets and the fin-type active region;
• a gate insulating layer between the nano-sheets and the gate;
• a source/drain region on the fin-type active region on opposite sides of the at least one nano-sheet;
• inner spacers between the source/drain region and the sub-gate portion and between the nano-sheets;
• and
• a source/drain protection layer on a sidewall of the at least one nano-sheet, and between the source/drain region and the at least one nano-sheet.