A semiconductor device, comprising: a substrate that includes an integrated circuit region; a first interlayer insulation film formed above the substrate; a second interlayer insulation film (111, 112), which is formed above the first interlayer insulation film; a main-wall part that is formed in the first interlayer insulation film and in the second interlayer insulation film, the main-wall part surrounding the integrated circuit region in a plan view and including a first bend section in a corner region of the semiconductor device in a plan view; a first sub-wall part (3a, 3c, 3d1, 3e1, 3f2), which is located between the integrated circuit region and the first bend section in a plan view, the first sub-wall part being formed in the first interlayer insulation film and in the second interlayer insulation film (111, 112) and including an L-shaped portion; a contact hole formed in the first interlayer insulation film of the integrated circuit region in a plan view; a first trench formed in the first interlayer insulation film; a second trench formed in the first interlayer insulation film, the second trench being apart from the first trench in the corner region in a plan view; a third trench, which is formed in the second interlayer insulation film (111, 112), the third trench being wider than the first trench in a plan view; a fourth trench, which is formed in the second interlayer insulation film (111, 112) and is wider than the second trench in a plan view, the fourth trench being apart from the third trench in the corner region in a plan view; a fifth trench, which is formed in the second interlayer insulation film of the integrated circuit region in a plan view; a first metal film, which is formed in the contact hole, the first trench, and the second trench; and a second metal film, which is formed in the third trench, the fourth trench and the fifth trench, wherein: the third trench is located directly above the first trench; the fourth trench is located directly above the second trench; the main-wall part includes the first trench and the third trench; and the first sub-wall part (3a, 3c, 3d1, 3e1, 3f2) includes the second trench and the fourth trench. a substrate that includes an integrated circuit region; a first interlayer insulation film formed above the substrate; a second interlayer insulation film (111, 112), which is formed above the first interlayer insulation film; a main-wall part that is formed in the first interlayer insulation film and in the second interlayer insulation film, the main-wall part surrounding the integrated circuit region in a plan view and including a first bend section in a corner region of the semiconductor device in a plan view; a first sub-wall part (3a, 3c, 3d1, 3e1, 3f2), which is located between the integrated circuit region and the first bend section in a plan view, the first sub-wall part being formed in the first interlayer insulation film and in the second interlayer insulation film (111, 112) and including an L-shaped portion; a contact hole formed in the first interlayer insulation film of the integrated circuit region in a plan view; a first trench formed in the first interlayer insulation film; a second trench formed in the first interlayer insulation film, the second trench being apart from the first trench in the corner region in a plan view; a third trench, which is formed in the second interlayer insulation film (111, 112), the third trench being wider than the first trench in a plan view; a fourth trench, which is formed in the second interlayer insulation film (111, 112) and is wider than the second trench in a plan view, the fourth trench being apart from the third trench in the corner region in a plan view; a fifth trench, which is formed in the second interlayer insulation film of the integrated circuit region in a plan view; a first metal film, which is formed in the contact hole, the first trench, and the second trench; and a second metal film, which is formed in the third trench, the fourth trench and the fifth trench, wherein: the third trench is located directly above the first trench; the fourth trench is located directly above the second trench; the main-wall part includes the first trench and the third trench; and the first sub-wall part (3a, 3c, 3d1, 3e1, 3f2) includes the second trench and the fourth trench. the third trench is located directly above the first trench; the fourth trench is located directly above the second trench; the main-wall part includes the first trench and the third trench; and the first sub-wall part (3a, 3c, 3d1, 3e1, 3f2) includes the second trench and the fourth trench.