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Marcy’s Musings: Additive Processes, Signal Consequences

Signal integrity and additive manufacturing, particularly in metallization, are defining themes in modern PCB design and fabrication. PCB layouts are meticulously engineered systems designed to meet strict electrical and power performance targets. However, achieving those targets does not end at the design stage. Once a design enters fabrication, metallization processes—the precise plating of conductive traces—play a critical role in ensuring that signal speed, reliability, and integrity are achieved in the final physical board.

As increasingly smaller electronic devices become more complex and performant, maintaining signal integrity becomes significantly more challenging. Higher data rates, tighter geometries, and denser routing all introduce new risks, from impedance mismatches to electromagnetic interference.

The industry is increasingly turning to modified semi-additive processing (mSAP) and semi-additive processing (SAP) to address these challenges, as these advanced approaches allow for finer feature definition, improved line-edge precision, and tighter tolerances than traditional subtractive methods. The result is better control over electrical performance and a pathway to supporting next-generation applications. At the same time, these technologies represent a fundamental shift for PCB fabricators because they require new materials, processes, and ways of thinking about production.

This issue of I-Connect007 Magazine explores these developments in depth, beginning with contributions from PCB007 authors focused on additive technologies. Columnist Don Ball provides a foundational overview, starting with conventional electroplating methods and progressing through mSAP and SAP processes. He examines how these approaches influence etching performance and highlights which techniques have proven effective and which have not. Expanding on the chemistry of metallization, Melbs LeMieux of Electroninks offers insight into complex metal inks and discusses how his company is rethinking materials at the molecular level.

Carmichael Gugliotto of MacDermid Alpha Electronics Solutions writes about the importance of direct metallization as a key enabler of advanced PCB manufacturing. He cites the growing demands placed on PCBs and substrates used in AI infrastructure and high-performance computing, where reliability and performance margins are increasingly tight. The engineering team at MKS’ Atotech addresses enhanced mSAP processes with a focus on microvia reliability, an area of critical concern in high density interconnect (HDI) designs, while also considering manufacturing efficiency. Notion Systems rounds out the semi-additive discussion with its inkjet solder mask technology, highlighting how digital deposition methods can improve precision and flexibility in PCB production.

Our Design007 contributors tackle the evolving challenges of signal integrity. Stephen V. Chavez writes about return-path discontinuities, while Kristin Moyer addresses common-mode and differential-mode noise in routing and signal integrity, as well as strategies for ensuring signal survival in increasingly hostile electromagnetic environments.

In his column, Barry Olney succinctly captures the shift in design philosophy: “Modern PCB design is no longer just about routing signals but about engineering transmission lines, maintaining continuous return paths, and managing resonant structures within multilayer boards.” Columnist John Watson reinforces this perspective by urging designers to move beyond schematic-level thinking and consider the electromagnetic fields surrounding traces, dispelling the notion that signal integrity is somehow “black magic.”

Meanwhile, Kelly Dack explores how AI-driven design tools are pushing boundaries, transforming signal integrity from a niche concern into a decisive factor in determining product success, and shares a list of PCB designers who have had the most influence on him and the industry.

This issue also features a range of forward-looking discussions tied to advanced manufacturing. Anaya Vardya focuses on integrating flex circuits into advanced packaging solutions. A new contributor, Flexiramics, introduces innovative approaches to reinforcement materials for electronic packaging. Mike Carano contributes insights into the role of organic solderability preservatives (OSPs) in advanced packaging and where they provide the most value. Chandra Gupta of Remtec examines RF design and integration, emphasizing that true performance gains often occur at the interfaces, where components either work in harmony or conflict.

Additional design-focused content includes a conversation between Paul Cooke and Kelly Dack on designing for reliability, as well as Matt Stevenson’s overview of conductive via fill and what designers need to understand. Tracy Riggan interviews the leaders of the IPC-2581 Consortium about progress toward replacing Gerber files with a more secure and comprehensive data standard.

Happy Holden bridges the gap between design and fabrication by reviewing the growing role of digital twins, which integrate design and manufacturing data to improve outcomes, particularly as access to experienced manufacturing experts declines. In PCB fabrication, Richard Nichols continues his ongoing exploration of zero liquid discharge. We spotlight a roundtable discussion on cybersecurity and CMMC certification, and I explore the implications of the e-glass shortage in the AI era.

Together, these perspectives highlight, once again, that our industry is in transition, where innovation in materials, processes, and design methodologies is essential to meeting the demands of increasingly complex electronics systems.

This column originally appeared in the May 2026 issue of I-Connect007 Magazine.