advanced

**Advanced Substrate Technology** is **Ajinomoto Build-up Film and alternatives enabling fine-pitch interconnects, high-density routing, superior electrical/thermal properties** — advanced substrates support next-generation packages. **ABF** proprietary laminate build-up process. **Core** glass-reinforced resin core. **Build-Up Layers** sequential: copper layer patterned, insulation deposited, repeat. 4-16 copper layers typical. **Via-in-Pad** vias directly under component pads; maximum density. **Micro-Vias** 20-50 μm vias via sequential lamination + drilling. **Trace Pitch** 40-50 μm (advanced) vs. 100 μm (standard). **Layer Count** modern: 6-16 copper layers vs. 4-8 older. **Materials** polyimide, epoxy insulation; copper traces. **Impedance Control** 50Ω, 100Ω differential. High-speed signal routing. **Power Planes** distributed throughout substrate. Low impedance. **Thermal Vias** dedicated vias improve die-to-PCB coupling. **Loss** low-loss materials (ceramic-filled organics, LTCC) for RF. **CTE** matched to components (~12-17 ppm/K). **Tg** high-Tg (>180°C) withstands lead-free reflow (>250°C). **Moisture** absorption affects dimensional changes. Pre-bake recommended. **Manufacturing** complex multi-step: lamination, drilling, patterning, plating. **Cost** expensive vs. FR-4 but enables higher density. **Yield** tight tolerances (±25 μm); yields >95%. **Design Rules** lithography/etching specifications; CAD enforces. **RF** low-loss substrates for mmWave applications. **Testing** ICT (in-circuit test); AOI, X-ray inspection. **Advanced substrates enable next-generation packaging** through dense interconnects and superior properties.