Fineline & HDI Printed Circuits
Ultra-Fine-Pitch, High-Density Circuits for Compact, High-Performance Electronics
Fineline and HDI (High Density Interconnect) printed circuit boards are engineered to support miniaturization, high-speed signals, and dense component integration. PICA’s advanced PCB and flex manufacturing enables fine-line trace widths, laser micro-vias, ultra-thin dielectrics, and multi-build-up stack-ups that meet the demands of today’s wearable, RF, medical, automotive and high-frequency systems.
Learn more about what you need to know when designing for fineline and HDI PCBs. Read more here.
Why Choose Fineline / HDI Printed Circuits?
• Superior Component Density – Enables packing more I/O and functionality in a smaller footprint.
• Ultra-Fine Trace Capability – Achieve line/space down to 25–50 µm, using subtractive or mSAP/mSAP-like processing.
• Micro-Via & Via-In-Pad Support – Laser-drilled micro-vias, stacked or staggered, allow escape routing from dense BGAs and high-pin-count packages.
• High-Speed & RF-Ready Performance – Controlled impedance, ultra-thin dielectrics (as low as 12–25 µm) and low-loss materials support high-frequency and mixed-signal designs.
• Manufacturability & Reliability – Early DFM engagement, strict etching control, and 100% AOI ensure high yields in fine-line builds.
• Flex-HDI & Dynamic-Flex Options – Combine flexible arms + HDI cores or even dynamic-flex fine-line sections for moving applications.
Fineline PCB Capabilities – Highlights
• Laser Direct Imaging (LDI) for line/space ≈1 mil (≈25 µm) in rigid, flex, and rigid-flex builds.
• Ultra-Thin Copper options including rolled-annealed (RA) and thin electrolytic foils for improved fine-line routing and bend reliability.
• Multi-build-up HDI stack-ups such as 1+N+1, 2+N+2, and flex HDI buildup structures.
• Blind, buried, stacked and staggered micro-vias ≤ 0.15 mm with copper fill and via-in-pad options.
• Modified Semi-Additive Process (mSAP / mSAP-like) for <50 µm fine-line routing and controlled sidewall geometry.
• Thin dielectric materials (down to ~12–25 µm) for impedance targets, RF performance, and compact trace separation.
• Integrated rigid-flex HDI, dynamic flex + fine-line hybrid designs, and thin-core options for harsh environments.
• Inspection & Quality Assurance: AOI, X-Ray, flying probe, impedance verification, and micro-section analysis.
• Engineering Support: early layout review, stack-up optimization, micro-via strategy, reliability modeling, and material selection.
For technical information on PICA’s Fineline Flex PCB capabilities, click the button below.
Global Design & Manufacturing Support
With engineering teams in the U.S. and manufacturing in Malaysia, PICA supports prototypes through scaled production. We collaborate early to optimize stack-ups, choose low-loss materials, refine micro-via strategy, tune line/space limitations, and control impedance from Day 1. This prevents cost overruns, improves yield, and accelerates time-to-market for high-density builds.
Benefits of Fineline / HDI Circuits
High-Density Designs
Fineline/HDI builds enable greater routing density and component placement in smaller form factors—ideal for compact RF, sensor, and high-speed modules.
Enhanced Signal Integrity
Ultra-thin dielectrics, tight trace spacing, and precise etching improve impedance accuracy, reduce skew, and maintain low-loss transmission paths.
Miniaturization-Ready
Sub-50 µm traces and stacked micro-vias enable smaller boards, more features, and lighter assemblies without sacrificing reliability.
Manufacturing Efficiency
Controlled etching, LDI, copper fill via-in-pad, and automated inspection deliver high first-pass yield and minimized scrap—reducing total cost.
Dual-Flexibility
HDI isn’t limited to rigid boards. PICA supports rigid-flex HDI and dynamic-flex fine-line builds, enabling motion + density in one circuit.
Markets We Serve with Fineline / HDI Circuits
Mobile & Wearable Devices
Foldables, compact wearables and IoT modules rely on ultra-dense PCB real-estate and precision interconnects—ideal for HDI and flex HDI.
Medical Devices
Miniaturized sensors, implantables, and micro-assemblies demand ultra-fine routing, controlled impedance, and high-reliability micro-vias.
Automotive & Transportation
ADAS modules, radar systems and harsh-environment controls benefit from fine-line HDI that withstands vibration and thermal stress.
Telecommunications & 5G Infrastructure
RF modules, mmWave antenna arrays, and interposers require ultra-thin dielectrics, fine-line routing and stable impedance control.
Industrial & Defense Electronics
Rugged systems in UAVs, aerospace, and high-density sensor modules rely on fine-line durability, reliability, and extreme miniaturization.
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