Methods of reducing the floating body effect in vertical transistors are disclosed. The part of the conductor film at least forming the aforementioned wire bonding sections contains an Ag-based metal formed of Ag or an alloy having Ag as the main constituent and a metal oxide which coats said Ag-based metal and which has, as a constituent element, any of the elements selected from the group consisting of Al, Zr, Ti, Y, Ca, Mg, and Zn. Unique fingerprinting words are defined where each includes at least one spread sequence. A conductive bonding wire connects the end portions of the conductive connecting materials and the connection terminal respectively. The base can be stably positioned on a flat surface and the pawls resiliently clamp the insertion portion of the lighting unit so that the stability of positioning the lighting unit can be improved.