| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide an inexpensive BGA package which is suited for mass production by preventing the warpage of a base film due to reflow heat and easily mounting to a substrate in a semiconductor device in a film carrier system. SOLUTION: A copper foil wiring 3 is bonded to a base film 2 and the upper portion is covered with cover resist 8. An electrode 4 of a semiconductor IC chip 1 is joined to an inner lead 5 of the copper foil wiring 3 and the semiconductor chip is sealed with a sealing resin 6. Solder ball is supplied from an opening 8b of a cover resist 8 to a land 7, thus forming a bump 9. By bending four sides of the film 2, a bent part 10 is formed. Since the strength of the edge of the film 2 increases by the bent part 10, warpage and undulation decrease, thus achieving a simultaneous mounting to a substrate along with such electronic part as QFP. The recommended bending angle is equal to and more than 20 deg. and less than 90 deg. for a film surface and further strength can be obtained by bending in two stages.</p> |
