Methods relating to the fabrication of devices having conductive substrate vias with catch-pad etch-stops

An electronic device having a conductive substrate via extending between a conductor on a rear face and a conductor over a front face of the substrate includes a multi-layered etch-stop beneath the front surface conductor. The etch-stop permits use of a single etchant to penetrate both the substrate and any overlying semiconductor and/or dielectric without attacking the overlying front surface conductor. This is especially important when the semiconductor and dielectric are so thin as to preclude changing etchants when these regions are reached during etching. The etch-stop is preferably a stack of N>=2 pairs of sub-layers, where a first sub-layer comprises stress relieving and/or adhesion promoting material (e.g., Ti), and the second sub-layer comprises etch resistant material (e.g., Ni). In a further embodiment, where the device includes field effect transistors having feedback sensitive control gates, the etch-stop material is advantageously used to form gate shields.