Patent ID: 7569164
Filing Date: 2009-08-04
Classification: B23K,H05K,Y10T

Abstract:
1. A solder precoating method of forming solder bumps by forming a dam around electrodes on a substrate, filling a solder paste composition over the electrodes within opening parts surrounded by the dam, and heating the solder paste composition filled, so that solder is adhered to surfaces of the electrodes, wherein the method uses a solder paste composition containing solder powder, which is of a particle size distribution in which particles having a particle size of below 10 μm are present 16% or more, particles having a particle size of 10 μm or more and below 20 μm are present, and a sum of the particles having a particle size of below 10 μm and particles having a particle size of 10 μm or more and below 20 μm is 90% or more.