Ultrafast laser micro welding

Micro manufacturing is often limited by the capacity to effectively join components together in a reliable fashion. Conventional methods based on interlayers (glue, solder, frit etc.) typically involve uncertainty in the final joined position or strength, or age badly due to creep and/or out-gassing.
Ultrafast laser microwelding has been the subject of significant sustained development in recent years. The combination of high precision, high speed and low thermal damage while removing the necessity for an interlayer presents a unique solution to the problems of bonding highly dissimilar materials.
In dissimilar material bonding, where only one material is transparent to the incident radiation, the advantage of an ultrafast laser lies in the combination of severely restricted thermal zones and the ability to trigger both non-linear absorption in the transparent material and linear absorption in the opaque material. This generates a small heated zone around the interface forming of plasma in both materials simultaneously. As the plasma mixes and cools a true weld is formed.
We will present the result of ultrafast laser welding of highly dissimilar materials, with an emphasis industrially relevant parameters such as strength, reliability, thermal contacting and the requirements for surface preparation.