Semiconductor device including through substrate vias and method of manufacturing the semiconductor device

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

• providing a substrate having a first surface and a second surface facing each other;
• forming an integrated circuit on the first surface of the substrate and a first interlayer insulating layer covering the integrated circuit;
• forming a first hole configured to penetrate through the first interlayer insulating layer of the substrate, extending from the first surface of the substrate toward the second surface in a vertical direction, and having a first planar cross-sectional area, and a second hole configured to penetrate through the first interlayer insulating layer of the substrate, extending from the first surface of the substrate toward the second surface in the vertical direction, and having a second planar cross-sectional area less than the first planar cross-sectional area;
• forming a first conductive layer on the first interlayer insulating layer, in the first hole, and in the second hole;
• reflowing the first conductive layer;
• and
• forming a second conductive layer on the first conductive layer.

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

• providing a substrate having a first surface and a second surface facing each other;
• forming an integrated circuit on the first surface of the substrate and a first interlayer insulating layer covering the integrated circuit;
• forming wirings and a second interlayer insulating layer on the first interlayer insulating layer;
• thinning the substrate by removing a portion of the substrate extending from the second surface of the substrate toward the first surface such that a third surface facing the first surface is formed;
• forming a first hole and a second hole each extending from the third surface of the substrate to the first surface of the substrate in a vertical direction, and having different planar cross-sectional areas from each other;
• forming a first conductive layer on the third surface of the substrate, in the first hole, and in the second hole;
• reflowing the first conductive layer;
• and
• forming a second conductive layer on the first conductive layer.