A winged angled needle assembly has a hub to which a proximal end portion of an angled needle having a sharpened tip portion is joined and a pair of wings attached to both sides of the hub and further includes a fixing member attached so as to support the wings and an extensible, contractible needle guard disposed between the hub and the fixing member so as to connect these two members. A bottom contact disposed on a bottom surface of the semiconductor structure is electrically connected to one of the n-type region and the p-type region. The first electrode and the semiconductor wafer form a cathode during electroplating of the semiconductor wafer.