Semiconductor device and manufacturing method thereof

A semiconductor device, comprising:

• a logic circuit chip including:
• a first substrate;
• and
• a logic circuit on the first substrate;
• and
• a semiconductor memory array chip that is overlaid on and coupled to the logic circuit chip, and including:
• a second substrate;
• a wiring layer including a plurality of wirings that are on the second substrate, each of the plurality of wirings containing copper and extending along a surface plane of the second substrate in a first direction, and the plurality of wirings being arranged along the surface plane of the second substrate in a second direction different from the first direction;
• a first insulating film below the wiring layer;
• a plug extending through the first insulating film in a third direction crossing the first and second directions and electrically connected to one of the plurality of wirings, the plug containing tungsten;
• and
• a second insulating film provided between the first insulating film and the plug, wherein
• the logic circuit, the layer including the plurality of wirings, the first insulating film, the plug, and the second insulating film are between the first substrate and the second substrate.

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

• forming a logic circuit on a first substrate;
• forming a layer including a plurality of wirings on a second substrate, such that each of the plurality of wirings extends along a surface plane of the second substrate in a first direction and that the plurality of wirings is arranged along the surface plane of the second substrate in a second direction different from the first direction, the each of the plurality of wirings containing copper;
• forming a first insulating film on the layer including the plurality of wirings;
• forming, in the first insulating film, an opening that extends along a depth direction of the second substrate in a third direction, at least partially on one of the plurality of wirings;
• forming a second insulating film in the opening;
• after the second insulating film is formed, forming a plug in the opening, such that the plug extends in the third direction in the opening and is electrically connected to the one of the plurality of wirings, the plug containing tungsten;
• and
• bonding a first side of the first substrate on which the logic circuit is formed and a second side of the second substrate on which the layer including the plurality of wirings, the first insulating film, the second insulating film, and the plug are formed.