Laser formed metallic connections

Solid metallic connections have been successfully formed between two standard levels of metallization using a focused infrared (IR) laser. This new process of laser formed connections has been used to link continuous chains and with resistances of less than 0.8 Ω per connection. A commercial laser repair system used extensively by the memory industry was employed to perform approximately 50 000 individual links without failure. The electromigration resistance is comparable to standard metal interconnect. This technology has the potential to replace laser fuse cutting techniques to implement repair schemes and it can be used to program wiring in multichip module-deposited (MCM-D) or wafer scale integration applications implemented on silicon substrates. Furthermore, because it is an additive process, it lends itself to redundancy for higher yield and reliability.