sup-bond underfill 底部填充胶.pdfVIP

底部填充系列 •Sup-bond Underfill Underfill  底部填充是一种用于焊球周围填 充，防止潮气，污染，同时为芯 片提供优异机械性能，帮助消除 焊球产生的应力的胶黏剂。为电 子产品在冷热循环、高温高湿， 震动等使用环境中提供可靠保护。 Underfill  Underfill is basically a glue that surrounds the bumps, keeps them from getting contaminated, and keeps themmoisture free. It also provides significant mechanical support for the chip that is crucial for enabling it to withstand structural stresses, which are primarily caused by repeated heating and cooling cycles during operation。 Underfill 底部填充的关键性能要求 Requirements of Underfill • 快速流动 Fast Flow • 快速固化 Fast Cure • 低应力 Low Stress • 低吸湿性 Low moisture absorption • 可维修 Reworkable • 适合的粘结强度 Exceptional Adhesion Underfill 影响underfill流动性的主要因素 Influence factors of the flow • θ: 接触角 contact angle • ƴ:表面张力 surface tension • µ 粘度 viscosity • θ →90º, cos θ → 0, t →∞ • h ↓, t ↑ • µ↓, t ↓ • ƴ↓ , t ↑ Underfill 返修 Rework 用热风枪加热到underfill胶的软化点以上 对需要维修的芯 片加热,然后从PCB板上移除芯片，再将焊锡和underfill从 基板上清楚干净 Use a heat gun heating to a temperature above the underfill’s softening point, then removed from the PCB and residual solder and underfill cleaned off the substrate. Underfill Underfill process Underfill Sup-bond undrfill主要性能优势 Key Features Benifits ofSup-bond undrfil