Wafer scale interconnections offer an approach for improved wiring in ultrahigh speed digital systems. Conventional packaging introduces excessive parasitics such as coupling, stray inductance and capacitance, and excessive delay. Fabrication of large amounts of wafer scale wiring (hundreds of meters of wiring) will require automated inspection and repair strategies. The focused ion beam (FIB) is uniquely suited to some of these tasks. In this paper, a high yield lift-off process is employed to fabricate the wafer wire. Residual defects in this process have been categorized and found amenable to detection and repair by using the ion milling capabilities of the focused ion beam. However, special steps are required to enhance the milling rates. Secondary electron imaging permits the inspection of surface defects, but precautions must be taken to neutralize charge build-up on insulators.
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