Patent ID: 7863187

Claim:
A method for forming an interconnect in a microfeature workpiece, the microfeature workpiece including a terminal and a substrate with a first side carrying the terminal and a second side opposite the first side, the method comprising: constructing an electrically conductive interconnect with a barrier material insulating the interconnect from the substrate and covering an end of the interconnect, the interconnect extending from the terminal to at least an intermediate depth in the substrate with the interconnect electrically connected to the terminal; removing material from the second side of the substrate and from the barrier material so that a portion of the interconnect projects from the substrate and the interconnect has an exposed, conductive surface at the end of the interconnect; depositing a first dielectric layer composed of a first material onto the exposed, conductive surface of the portion of the interconnect that projects from the substrate and thereby covering the portion of the interconnect that projects from the substrate; and depositing a second dielectric layer composed of a second material onto the first dielectric layer such that the second dielectric layer covers the first dielectric layer, wherein the first material is different than the second material, and wherein the first material is removable by a removal process that generally does not affect the second dielectric layer.