Linear movement direction of the stage and the actual deflection direction of the electron beam deflected by the first command signal for deflecting the electron beam in the linear movement direction of the stage do not necessarily align with each other for reasons such as the disposition precision of the stage driving device, a lens system, and the deflecting device. The stiffener includes: an insulating material layer; and a rigid plate mounted substantially parallel to a surface of the substrate in the insulating material layer, the rigid plate having formed therein a plurality of through holes, at least a part of the through holes being filled with the insulating material. The soldering partners are connected at the envisaged joining location by using a solder that is melted by energy emitted by the inductor.