abstract |
According to one embodiment of the present invention, an underbump metal (414) of a semiconductor device is formed on a semiconductor bond pad (128), and the underbump metal (414) is a graded region of chromium, copper, and nickel ( 404), and the presence of nickel in the stepped region (404) prevents tin from transferring from solder bumps and other tin sources to form a Cu 6 Sn 5 copper / tin alloy that is easy to peel off. Is done. |