Nihon Superior Develops Ultra Thin Pb-Free Solder Foil

Osaka based solder maker, Nihon Superior developed ultra thin lead-free solder foil, which can be used for high reliable connections such for semiconductor substrate’s plating layer and silicon wafer. The firm succeeded in thinning the foil to 2 micrometers with its original lead-free solder. The firm will also start to supply ultra thin rosin-cored lead-free solder.

Nihon Superior provides ultra thin lead-free solder foil in strip shapes with 0.002-1 millimeters of thickness, 25-100 mm of width or in ribbon shapes with 0.03-0.3 mm of thickness, 15-150 mm of width, 10-500 mm of length and 0.5-2 mm of slitting width.

The material is Nihon Superior’s original alloy “SN100C,” a tin based alloy with 0.7% copper, 0.05% nickel and slight addition of germanium. The melting point is 227degrees C. Other lead-free solder alloys such as tin-silver-copper would become non-uniform structure when rolled.

Ultra thin rosin-cored lead-free solder is 0.1-0.25 mm diameter, using another original alloy “SN100C (030)” improved to decrease sticking and flux scattering. The firm succeeded in thinning the product from previous 0.3 mm diameter.