Electronics system with direct write engineering change capability

Abstract

A electronics system and method are provided which allow engineering changes to be made to a substrate without requiring the addition of fly wires and without requiring relatively large areas of pads for attaching these wires. Each device site is surrounded by a series of engineering change ring patterns. A series of engineering change patterns allow change interconnections between device sites to be made. Fan-in metallizations extend inwardly to the device sites from these change patterns, with a series of vias making surface connections adjacent to the ring patterns. Fan-out metallizations extend from the device site pads to the ring patterns, with a series of vias making surface connections adjacent to the ring patterns. Engineering changes are made by directly writing surface metal deposits to make the appropriate connections between the vias and the ring pattern. The original chip pad connections and the new ring pattern connections can be appropriately isolated by laser deletions, if necessary.