Issue link: https://iconnect007.uberflip.com/i/1532052
24 SMT007 MAGAZINE I FEBRUARY 2025 Feature Article by Chrys Shea SHEA ENGINEERING SERVICES UHDI technology is more than another evo- lutionary level of miniaturization. It's a funda- mental change in how we create circuit boards, on a scale potentially as impactful as the tran- sition from through-hole to surface mount was 40 years ago. Traditional and high density interconnect (HDI) PCB manufacturing technology that uses subtractive copper etching processes cannot repeatably produce features below 75 microns and vias below 150 microns. UHDI fabrication blows those limits away with addi- tive or semi-additive processes that can pro- duce lines and spaces as small as 12 microns and vias of 75-100 microns, increasing circuit density by a whopping 10–30X. UHDI is not new or uncommon technol- ogy. It's in the palm of our hands as it's been in mobile products since the iPhone 6 launched in 2014. While it has proven its capabilities in con- sumer electronics, it needs significant develop- ment and evaluation to be considered robust enough for aerospace and defense electronics, where the benefits of miniaturization are exten- sive, but the implication of malfunction is far greater than in similar consumer-grade devices. As with most modern PCB fabrication tech- nologies, Asia leads America in the devel- opment and scaleup of UHDI. To realize the multitude of benefits from PCB densifica- tion in security and defense electronics, the U.S. government has begun funding R&D for Are Domestic Assemblers Ready for the Next Level of Electronics Miniaturization?