The first conductivity type contact 211″ is formed in the first conductivity type well 211′, and has the first conductivity type. The first conductivity type contact 211″ is located below the top surface 21a and in contact with the top surface 21a in the vertical direction, to serve as an electrical contact of the first conductivity type well 211′ . The second conductivity type contact 212″ is formed in the second conductivity type well 212′ , and has the second conductivity type. The second conductivity type contact 212″ is located below the top surface 21a and in contact with the top surface 21a in the vertical direction, to serve as an electrical contact of the second conductivity type well 212′.

The body region 26 is formed in the first high voltage well 22 within the device region 23a, and has the first conductivity type. The body region 26 is located below the top surface 21a and in contact with the top surface 21a in the vertical direction. The body contact 26′ is formed in the body region 26, and has the first conductivity type. The body contact 26′ is located below the top surface 21a and in contact with the top surface 21a in the vertical direction, to serve as an electrical contact of the body region 26. The deep well column 25 is formed in the first high voltage well 22 within the device region 23a, and has the first conductivity type. The deep well column 25 is in contact with the deep well 211, and is electrically connected to the deep well 211, but is not in contact with the top surface 21a in the vertical direction.