Semiconductor device and manufacturing method thereof to prevent a notch

摘要

A method for manufacturing a semiconductor device includes: preparing a substrate in which a first interlayer insulation layer having a first via hole and a first trench is formed; forming a first via plug and a first metal line by filling the first via hole and the first trench with a first metal; planarizing the first metal line and the first interlayer insulation layer; forming a second interlayer insulation layer on the first metal line and the first interlayer insulation layer; planarizing the second interlayer insulation layer; forming a second via hole and a second trench in the second interlayer insulation layer; forming a second via plug and a second metal line by filling the second via hole and the second trench with a second metal; and planarizing the second metal line and the second interlayer insulation layer.