Semiconductor device and manufacturing method thereof

A semiconductor device according to the present embodiment comprises a first electrode film. An interlayer dielectric film is provided on the first electrode film. A contact plug is provided in a contact hole that penetrates through the interlayer dielectric film and reaches the first electrode film. The contact plug includes a first metal film and a first conductive film configured to cover an inner wall of an upper portion of the contact hole. The contact plug includes a second metal film configured to cover the first conductive film on the inner wall of the upper portion of the contact hole and cover an inner wall of a lower portion of the contact hole. The contact plug includes a second conductive film configured to be filled inside the second metal film in the contact hole.