Patent ID: 7943861
Filing Date: 2011-05-17
Classification: H01L,H05K,Y10T

Abstract:
1. A printed wiring board comprising: a solder pad; a solder resist layer having an opening portion exposing the solder pad; and a structure for forming a composite layer on the solder pad and configured to receive a solder material, wherein the structure has a first layer comprising Ni and a second layer comprising Pd, the first layer is positioned on the solder pad, the second layer is positioned on the first layer, at least one of the first layer and the second layer has a degree of a thickness and contains an amount of P such that the composite layer which has Ni reaching to an interface between the composite layer and a solder structure is formed as a result of solder reflow of the solder material, a thickness of the second layer is 0.01-1.0 μm, and the second layer contains P of 2-7 wt %.