Lead frame and method for manufacturing the same
A lead frame comprises: a base metal layer; a copper plating layer, including one of a copper layer and an alloy layer including a copper, configured to plate the based metal layer to make a surface roughness; and an upper plating layer, including at least one plating layer including at least one selected from the group of a nickel, a palladium, a gold, a silver, a nickel alloy, a palladium alloy, a gold alloy, and a silver alloy, configured to plate the copper plating layer.
1. A lead frame, comprising:
a base metal layer;
a copper plating layer, including at least one of a copper layer and an alloy layer including a copper, configured to plate the base metal layer to make a surface roughness; and
an upper plating layer,
wherein the copper plating layer has a surface roughness (R a ) of 150 to 400 nm,
wherein the upper plating layer comprises a nickel plating layer including at least one material selected from the group consisting of nickel and nickel alloy.
2. The lead frame according to claim 1 , wherein the copper plating layer has a thickness of 0.3 to 1.5 μm.
3. The lead frame according to claim 1 , wherein the upper plating layer is a palladium plating layer including the palladium or the palladium alloy.
4. The lead frame according to claim 1 , wherein the upper plating layer is a gold plating layer ding the gold or the gold alloy.
5. The lead frame according to claim 1 , wherein the upper plating layer comprises two plating layers including a nickel plating layer including the nickel or the nickel alloy; and
a palladium plating layer, formed on the nickel plating layer, including the palladium or the palladium alloy.
6. The lead frame according to claim 1 , wherein the upper plating layer comprises three plating layers including a nickel plating layer including the nickel or the nickel alloy;
a palladium plating layer, formed on the nickel plating layer, including the palladium or the palladium alloy; and
a gold plating layer, formed on the palladium plating layer, including the gold or the gold alloy.
7. The lead frame according to claim 1 , wherein the base metal layer comprises at least one of a copper layer and an alloy layer including a copper.
8. The lead frame according to claim 1 , wherein the nickel plating layer is formed in a thickness of 0.2 to 1 um.
9. The lead frame according to claim 3 , wherein the palladium plating layer is formed in a thickness of 0.02 to 0.08 um.
10. The lead frame according to claim 4 , wherein the gold plating layer is formed in a thickness of 0.003 to 0.01 um.
11. A method for manufacturing a lead frame, comprising:
providing a base metal layer;
forming a copper plating layer, including at least one of a copper layer and an alloy layer including a copper, plating the base metal layer to make a surface roughness; and
forming an upper plating layer, including at least one layer constituted with at least one selected from the group of a nickel, a palladium, a gold, a silver, a nickel alloy, a palladium alloy, a gold alloy, and a silver alloy, configured to plate the copper plating layer,
wherein forming the copper plating layer comprises performing a copper sulfate plating process for 10 to 40 seconds under a copper ion concentration of about 5 to 70 g/L and a current density of about 3 to 7 ASD, and
wherein the copper plating layer is formed to have a surface roughness (R a ) of 150 to 400 nm.
12. The method according to claim 11 , wherein the upper plating layer is a nickel plating layer including the nickel or the nickel alloy.
13. The method according to claim 11 , wherein the upper plating layer is a palladium plating layer including the palladium or the palladium alloy.
14. The method according to claim 12 , wherein the upper plating layer is a gold plating layer including the gold or the gold alloy.
15. The method according to claim 11 , wherein the forming a copper plating layer comprises a copper sulfate plating process to plate the base metal layer with the copper.
16. The method according to claim 11 , wherein the forming an upper plating layer comprises:
forming a nickel plating layer including the nickel or the nickel alloy to plate the copper plating layer; and
forming a palladium plating layer, formed on the nickel plating layer, including the palladium or the palladium alloy.
17. The method according to claim 11 , wherein the copper plating layer has a thickness of 0.3 to 1.5 μm.
18. The method according to claim 11 , wherein the forming an upper plating layer comprises:
forming a nickel plating layer including a thin film of the nickel or the nickel alloy to plate the copper plating layer, wherein the thin film of the nickel or the nickel alloy has a thickness in a range of from 0.2 to 1 μm;
forming a palladium plating layer, formed on the nickel plating layer, including the palladium or the palladium alloy; and
forming a gold plating layer, formed on the palladium plating layer, including the gold or the gold alloy.