US Patent 7391636 Semiconductor memory device and arrangement method thereof

A semiconductor memory device and an arrangement method thereof are included. The semiconductor memory device includes column selecting signal lines and global data IO signal lines arranged on the same layer in the same direction above a memory cell array; word lines and first local data IO signal lines arranged on a different layer from the column selecting signal lines above the memory cell array, in a perpendicular direction to the column selecting signal lines; and second local data IO signal lines arranged on a different layer from the column selecting signal lines and the word lines above the memory cell array, in the same direction as the first local data IO signal lines.