Chatting Ultra HDI: Chrys Shea, PCB Miniaturization & Challenges Ahead

OnTrack · 2 Apr 2024 · 47m · Episode 260

What this episode covers

Chrys Shea, President of Shea Engineering, explains the design and utility of advanced test vehicles for Ultra High-Density Interconnect (UHDI) assembly, focusing on challenges like the leading edge effect and tombstoning. She details how her latest board quantifies solder paste variation and tests off-axis placement, while also addressing Surface Insulation Resistance (SIR) and the trade-offs of using minimum IPC pad sizes. The discussion highlights the importance of early DFM collaboration between designers and assemblers to mitigate defects like tombstoning and mask misregistration in high-volume manufacturing.

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