The present invention discloses a method for manufacturing a semiconductor device, comprising the steps of: providing a semiconductor substrate on which cell strings are formed and in which a plurality of conductive regions are formed; sequentially forming a first interlayer insulation film and a first etch barrier film on the semiconductor substrate; forming a plurality of contact holes by exposing the plurality of conductive regions formed in the semiconductor substrate, wherein an impurity concentration of the conductive regions is reduced due to the process for forming the contact holes; filling a metal material in the contact holes and forming a plurality of contact plugs; sequentially forming a second interlayer insulation film, a second etch barrier film and a third interlayer insulation film over a resulting structure including the contact plugs; forming a plurality of metal line patterns, wherein the metal line patterns pass through the third interlayer insulation film, the second etch barrier film and the second interlayer insulation film and contact to the contact plugs; forming a fourth interlayer insulation film over a resulting structure including the plurality of metal line patterns; forming a plurality of metal line contact holes by patterning the fourth interlayer insulation film; and forming a plurality of metal line contact plugs in the plurality of metal line contact holes by filling a metal material in the metal line contact holes.