Copper is used extensively for interconnections within the electronics industry and welding by laser is an alternative to soldering which gives higher reliability and greater strength than a soldered joint.
Laser welding of copper has traditionally required high peak power pulsed lasers to overcome the inherent high reflectivity and thermal conductivity of the base material. At room temperature copper absorbs as little as 5% of laser light at 1 micron wavelength. A new patented process of mixing in a secondary wavelength at 532nm (only 10-15% of the total energy) enables the absorption of laser energy to be much improved, offering consistent results even where there are differences in the surface condition of the material. Read the full article here… LASAG Goes Green to Weld Copper