Terminal structure, printed wiring board, module substrate, and electronic device

摘要

The present invention relates to a terminal structure and an electronic device having the terminal structure. The terminal structure includes: a terminal having: a conductor layer containing at least one metal selected from gold, silver, and copper; a first layer containing nickel and phosphorus, laid on the conductor layer; a second layer having a smaller atomic ratio of nickel to phosphorus than the first layer and containing Ni3P, laid on the first layer; and a third layer containing a first intermetallic compound of an Ni—Cu—Sn type, laid on the second layer; and a solder layer on the third layer of the terminal. A second intermetallic compound of an Ni—P—Sn type partly covers a surface of the second layer on the third layer side and a maximum thickness of the second intermetallic compound in a lamination direction is from 0.05 to 0.7 μm.

主权项

1. A terminal structure comprising:
a terminal having:
a conductor layer containing at least one metal selected from gold, silver, and copper;a first layer containing nickel and phosphorus, laid on the conductor layer;a second layer having a smaller atomic ratio of nickel to phosphorus than the first layer and containing Ni3P, laid on the first layer;a third layer containing a first intermetallic compound of an Ni—Cu—Sn type, laid on the second layer; anda solder layer on the third layer of the terminal, wherein a second intermetallic compound of an Ni—P—Sn type partly covers discontinuously a surface of the second layer on the third layer side and a maximum thickness of the second intermetallic compound in a lamination direction is from 0.05 to 0.7 μm, and wherein the second intermetallic compound is not in contact with the solder layer.