Patent ID: 7071724

Claim:
An apparatus for testing a device wafer having a plurality of devices formed thereon, comprising: an interface wafer having a first surface and a second surface, the interface wafer comprising: a plurality of contact pads disposed on the first surface for contacting a plurality of device pads on the device wafer; a plurality of interface pads disposed on the second surface for contacting probe needles on a probe card, wherein the plurality of interface pads are electrically connected to the plurality of contact pads; a first interconnect layer having one or more first interconnect lines, each interconnect line electrically connecting a respective first set of contact pads, wherein the first interconnect layer is disposed within the interface wafer; and a second interconnect layer, disposed within the interface wafer, having one or more second interconnect lines, each second interconnect line electrically connecting a respective second set of contact pads.