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JULY 2026 I I-CONNECT007 MAGAZINE 39 In a conventional multilayer board, yield is relatively linear. In ELIC, yield is multiplicative across cycles. Based on our production experience at ASC, if pro- cess capability at each build cycle delivers 99% yield per cycle, a six-cycle ELIC build produces a cumulative yield starting point of approximately 94% before final electrical test, AOI, and assem- bly. A fabricator running 97% yield per cycle on the same six-cycle build arrives at a starting yield below 84%. That gap compounds with every layer and is the single largest driver of cost variability between ELIC suppliers. This is why process maturity at each individual build step matters more in ELIC than in any prior technology category. Evaluating ELIC suppliers on production yield data for comparable builds—not just stated capability limits—is the right approach. In ELIC, design variables are tightly intercon- nected in ways that have no parallel in standard HDI. In Table 2, when a fabricator says "it depends" in response to an ELIC design question, this is the reason. No single variable moves independently. This is what makes ELIC closer to semiconductor packaging than traditional PCB manufacturing. When ELIC Is Viable vs. Impractical for Production The tipping point is best understood through three lenses: technical necessity, volume economics, and supplier readiness. On the technical side, ELIC becomes the right choice when the design cannot be executed in a 2-4-2 or 3-2-3 HDI architecture. If a designer can achieve their density requirements with three or fewer sequential build-up cycles, they should do it. The yield and cost model will be better, and the supply chain is broader. Four or more build-up cycles is generally where ELIC becomes the appro- priate architecture. Figure 3: A 2% per-cycle process capability gap compounds into a 10.8% yield difference by cycle 6. This is the single largest driver of cost variability between ELIC suppliers, and the reason supplier process maturity matters more than stated capability limits.