Terminal
According to this invention, provided is a terminal having a plating layer formed on a surface of a base, the plating layer having a structure in which an intermetallic compound crystal that contains Sn, Cu, Cr and Ni, is dispersed in a parent phase that contains Sn and an Sn—Cu alloy.
1. A terminal having a plating layer formed on a surface of a base,
the plating layer having a structure in which an intermetallic compound crystal that contains Sn, Cu, Cr and Ni, is dispersed in a parent phase that contains Sn and an Sn—Cu alloy,
wherein the intermetallic compound crystal has a chemical composition represented by:
50 to 70% by mass of Sn;
30 to 50% by mass of Cu;
0.001 to 3% by mass of Cr; and
0.01 to 6.5% by mass of Ni.
2. The terminal according to claim 1 , wherein the plating layer has a chemical composition represented by:
0.7 to 15% by mass of Cu;
0.001 to 1% by mass of Cr;
0.01 to 5% by mass of Ni;
0.1% by mass or less of an inevitable impurity and the balance of Sn,
and the parent phase has a chemical composition represented by 5% by mass or less of Cu, 1% by mass or less of Ni, 1% by mass or less of Cr, 0.1% by mass or less of an inevitable impurity and the balance of Sn.
3. The terminal according to claim 1 , further comprising a layer of titanium, nickel or nickel alloy formed under the plating layer.
4. The terminal according to claim 1 , wherein the base comprises aluminum, aluminum alloy, copper, copper alloy or stainless steel.
5. The terminal according to claim 1 , wherein the base comprises Si, SiC or GaN.
6. A bump having a plating layer formed on a surface of a base,
the plating layer having a structure in which an intermetallic compound crystal that contains Sn, Cu, Cr and Ni, is dispersed in a parent phase that contains Sn and an Sn—Cu alloy,
wherein the intermetallic compound crystal has a chemical composition represented by:
50 to 70% by mass of Sn:
30 to 50% by mass of Cu;
0.001 to 3% by mass of Cr; and
0.01 to 6.5% by mass of Ni.