A method for forming an interconnection element having metalized structures includes forming metalized structures in an in-process unit that has a support material layer with first and second spaced-apart surfaces defining a thickness therebetween, a handling structure, and an insulating layer separating at least portions of the first surface of the support material layer from at least portions of the handling structure. The metalized structures are formed extending through the thickness of the support material layer. The method also includes etching at least a portion of the insulating layer to remove the handling structure from the in-process unit and further processing the in-process unit to form the interconnection element.