Laser Welding for Microelectronic Interconnections

The ability to join dissimilar materials having markedly different thicknesses (ratio of 50:1) is shown to be possible using a LASER. The feasibility of welding to thin films has been demonstrated by metallurgical examination of the welded connection. Welds were evaluated by visual inspection, macrosection, and microsection. Preliminary results of substrate studies indicate that unglazed alumina is a satisfactory material. LASER welding, having been demonstrated as a useful interconnection method, can be developed through additional investigation for extensive application to microelectronic circuitry.