| 摘要 |
A lead frame includes a base material having a front surface for mounting of a semiconductor chip and a back surface for connection with an external board, and an Ni layer having a thick section and thin section. The thick section is formed on the back surface of the base material, whereas the thin section is formed on all or a part of the front surface of the base material. It is preferable that the thick section has a thickness ranging from 2.5 to 5 μm, and the thin section is 0.5-2 μm thinner than the thick section. The lead frame can be manufactured with improved productivity by forming an Ni layer on both front and back surfaces of the base material, and then etching only the Ni layer formed on the front surface of the base material. |
