| 摘要 |
<p>PROBLEM TO BE SOLVED: To secure an enough connective reliability when with a flexible wiring board a semiconductor element to be mounted thereon is connected through a wire-bonding, by providing a gold pad in the flexible wiring board, and by setting the dynamic Vickers hardness of the gold pad to a value not smaller than a specific value. SOLUTION: After interposing between a base layer 1 and a cover layer 2 a conductor layer 3 forming a predetermined circuit pattern, a reinforcing layer 4 is provided on the rear surface of the base layer 1 via a bonding-agent layer 9, and a gold pad 5 is provided in the cover layer 2. Then, after so forming in an opening portion 6 of the cover layer 2 a nickel plating layer 7 as an underlay as to form thereon a gold plating layer 8, there is made not smaller than 50 the dynamic Vickers hardness of this gold pad 5 which is measured from the size of the recess generated by scqueezing the Vickers indenter of an equilateral rectangular pyramid into the testing surface of the sample of the gold pad 5 through a certain testing load. As a result, the connective reliability of a wire-bonding can be secured.</p> |
