| 摘要 |
A method of selectively adjusting surface tension of a soldermask material. Specifically, a method of selectively adjusting the surface tension of a soldermask material to promote adhesion of a molding compound in a ball grid array package while maintaining a low surface tension on the ball attach area to prevent bridging between the solder balls. Solder balls require a low surface tension soldermask to minimize bridging, while the molding compound requires a high surface tension to provide adequate adhesion to the surface of the soldermask. By exposing selected portions of the soldermask to an activation method, such as ultra-violet radiation, the surface tension of the soldermask can be varied such that different areas of the package exhibit different surface tensions.
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