A method of forming and testing an interposer includes forming vias in a semiconductor material of a wafer having a front side and a back side. The method further includes disposing an electrically conductive layer on the front side of the wafer such that the layer is electrically connected to the vias. The method also includes forming electrically conductive pads on the front side of the wafer, wherein each electrically conductive pad is electrically connected to the electrically conductive layer. The method further includes forming electrically conductive bumps on the back side of the wafer, wherein each electrically conductive bump is electrically connected to at least one via. The method also includes testing electrical connectivity from a first bump to a second bump of the electrically conductive bumps.