Supplemental multilevel interconnects by laser direct writing: Application to GaAs digital integrated circuits

Abstract
A nonperturbing sequence of laser direct-writing processes is described for applying supplemental multilevel interconnects on partially or fully fabricated circuits. The approach adds multiple levels of laser direct-written tungsten metallization and is demonstrated here for the assembly of a simple latch circuit on a standard GaAs digital test chip. Principal applications are for subsystem verification, device testing, restructuring, and fault avoidance on Si and GaAs circuits.