Semiconductor device

A semiconductor device comprising:

• a first film including a first side and a second side opposite each other;
• a second film including a third side and a fourth side opposite each other, the third side of the second film being in contact with the second side of the first film;
• a wiring including a first portion and a second portion,
• the first portion having a first width and extending from the fourth side of the second film toward the first film,
• the second portion below the first portion and having a second width, and
• the second width being smaller than the first width;
• and
• a plug conductive film extending from the first side of the first film to penetrate a bottom face of the wiring, an uppermost face of the plug conductive film and a part of side walls of the plug conductive film being in contact with the wiring;
• and
• a via including an insulating liner between the plug conductive film and the first film.

A semiconductor device comprising:

• a substrate including a first side and a second side opposite each other;
• an active pattern on the first side of the substrate;
• a source/drain region in contact with the active pattern;
• a frontside wiring structure on the first side of the substrate, the frontside wiring structure extending in a first direction and being electrically connected to the source/drain region;
• a through contact via electrically connected to the source/drain region, the through contact via because spaced apart from a side of the source/drain region;
• a buried wiring in the substrate and electrically connected to the through contact via;
• and
• a backside wiring structure electrically connected to the buried wiring, the backside wiring structure on the second side of the substrate, wherein
• the buried wiring includes a first portion and a second portion below the first portion,
• the first portion extends from the second side of the substrate toward the first side,
• the first portion has a first width, and
• the second portion has a second width, and
• the second width is smaller than the first width,
• the through contact via includes a plug conductive film and an insulating liner,
• the plug conductive film penetrates through an upper face of the second portion,
• a lowermost face of the plug conductive film and a part of a side wall of the plug conductive film are in contact with the buried wiring, and
• the insulating liner extends along the side wall of the plug conductive film.