An integrated circuit includes a first diffusion area for a first type transistor. The first type transistor includes a first drain region and a first source region. A second diffusion area for a second type transistor is separated from the first diffusion area. The second type transistor includes a second drain region and a second source region. A gate electrode continuously extends across the first diffusion area and the second diffusion area in a routing direction. A first metallic structure is electrically coupled with the first source region. A second metallic structure is electrically coupled with the second drain region. A third metallic structure is disposed over and electrically coupled with the first and second metallic structures. A width of the first metallic structure is substantially equal to or larger than a width of the third metallic structure.