Picoliter Solder Droplet Dispensing for Electronics Manufacturing

本研究提出了一种新的焊料应用方法，即使用喷墨印刷技术，在各种基材上生产和放置熔融焊料液滴。基于喷墨的焊锡沉积成本低（不需要掩模或屏幕），灵活（图像以数字方式存储和形成），适合制造环境（不像液态金属离子系统那样在真空中操作），高度可重复性和高分辨率。具体应用将包括在集成电路上形成焊料凸起，用于TAB或倒装芯片互连，或选择性地将顶部金属化用于细间距表面贴装组装、片上芯片（COB）或多芯片模块（MCM）。直写焊料技术将是返工的理想选择，包括芯片或封装更换，以及高密度互连（HDI）基板的金属化或个性化电路。

This research addresses a new solder application method, using ink-jet printing technology, to produce and place molten solder droplets onto various substrates. Ink-jet based solder deposition would be low cost (no masks or screens are required), flexible (the image is stored and formed digitally), suitable for manufacturing environment (does not operate in a vacuum like liquid metal ion systems), highly repeatable, and high resolution. Specific applications would include formation of solder bumps on integrated circuits for TAB or flip-chip interconnection, or selective application of top metallization for fine pitch surface mount assembly, chip-on-board (COB), or multichip modules (MCM's). Direct-write solder technology would be ideal for rework, including both chip or package replacement, and metallization or personalization of circuitry for high density interconnection (HDI) substrates.