Method for fabricating a flexible substrate based ball grid array (BGA) package
Abstract
Abstract A flexible substrate based BGA package mainly comprises a semiconductor chip securely attached onto a flexible film substrate through a nonconductive adhesive. The flexible film substrate is formed from a flexible film having a chip attaching area for carrying the semiconductor chip. The upper surface of the flexible film is provided with a plurality of chip connection pads, a plurality of solder pads, and at least a dummy pad which is disposed centrally on the chip attaching area. The purpose of the dummy pad is to increase the rigidity and strength of the central part of the chip attaching area. The chip connection pads are arranged about the periphery of the chip attaching area for electrically connected to the semiconductor chip. The solder pads are disposed about the dummy pad(s) and electrically connected to the corresponding chip connection pads. The flexible film has a plurality of through-holes formed corresponding to the solder pads such that each solder pad has a portion exposed within the corresponding through-hole for mounting a solder ball. A package body is formed over the semiconductor chip and the upper surface of the flexible film substrate.
Inventors
- 👤 Kao-Yu Hsu
- 👤 Shih-Chang Lee
Bibliographic Details
Claims Analysis
Total Claims: 7References Cited (Backward Citations)
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