Focused electron and ion beam repair strategies for wafer-scale interconnections in thin film packaging - Lin, H.T.; McDonald, J.F.; Corelli, J.C.; Balakrishnan, S.; King, N. (Elsevier)
Thin film packaging employing wafer-scale or high density multilayer interconnections embedded in organic insulators is currently being studied intesively for high performance computers. Applications of this technology appear extremely promising for improving systems design by providing direct chip-to-chip interconnections on a multichip digital hybrid. High yield fabrication of these packages appears possible. However, even with the use of such techniques, defects can still arise in the most aggressive applications such as multilayer hybrids containing many layers or on large diameter wafers. Extensive studies of residual defects arising in a high yield, planarized lift-off process have been cataloged and some results are presented. These defects primarily include interconnection open circuits due to thermal stress cracking, bad vias, or failure to transfer patterns. Interlayer shorts due to lift-off brush metal, source splitting, or improper pattern transfer also arise. Finally, interlayer pinholes are occasionally still observed. Practical repair strategies are presented using a combination of focused electron beam and ion beam systems. An application of ion beam voltage contrast testing to the problem of checking line continuity and shorting is examined. Finally, a microfocused secondary ion mass spectrometer is used for verification of cuts produced from ion milling and investigation of vias.
http://linkinghub.elsevier.com/retrieve/pii/0040-6090(88)90372-0
Keywords: U