| 摘要 |
PURPOSE:To perform soldering of a junction between a head part and a semiconductor chip excellently, by forming a lead electrode, which is provided with the head part by header machining, by using a piece of tin covered conductor wire, and soldering the lead electrode and a chip. CONSTITUTION:A copper wire 11 undergoes header machining, and a head part having a large diameter is formed at the tip of a lead electrode 1. The head part 2 of the lead electrode 1 is soldered to the surface of a semiconductor diode chip 3. The wire 11 is a piece of tin-covered conductor wire. A tin layer 12 of the surface of the wire 11 expands on the end surface of the head part of the lead electrode 1 in the header machining. The tin coating film having good solder wettability and a thickness of about several microns is formed. Thus excellent soldering can be performed when the semiconductor chip 1 is bonded to the head part 2. Even after storage for a long period, the tin layer 12 on the surface of the lead electrode 1 ensures excellent solderability. |
