A server device may receive information, associated with a request for a conferencing call, from a call manager, which is responsible for establishing and handling conferencing calls. The vertical MISFETs comprise rectangular pillar laminated bodies each formed by laminating a lower semiconductor layer, an intermediate semiconductor layer, and an upper semiconductor layer, and gate electrodes formed on corresponding side walls of the laminated bodies with gate insulating films interposed therebetween. The gate electrode strip line extends opposite the electrically conductive substrate. The end portions of the tubular composite members may be connected to the inner surfaces of the metallic tube members in a variety of different ways.