High Layer PCB

Managing Signal Integrity for Complex Systems

Modern High Layer Count PCB technology addresses the demands of increasingly complex electronic systems by delivering robust multilayer architectures that support high-speed signal routing, high-power distribution, and dense interconnect requirements. With layer counts extending beyond traditional limits—often reaching 30, 40, or even 60 layers—these PCBs enable the integration of multiple functions within a single board, reducing system-level complexity and improving overall reliability.

At the core of High Layer PCB technology are advanced fabrication processes that ensure precision across every layer. Tight layer-to-layer registration, controlled impedance, back drilling, and high aspect ratio plating work in concert to maintain signal integrity across long traces and multiple interfaces. The use of high-performance materials—including low-loss dielectrics, high-Tg laminates, and hybrid stack-ups—further enhances performance in high-speed, high-frequency, and thermally demanding applications.

For systems that require complex routing architectures, dense power distribution networks, or the integration of multiple high-speed interfaces, High Layer PCBs deliver the routing capacity, signal fidelity, and mechanical stability that advanced applications demand. From telecommunications infrastructure and server backplanes to aerospace avionics and industrial control systems, High Layer Count PCBs provide the foundation for reliable, high-performance electronics.

What is High Layer PCB?

High Layer PCB, also known as High Layer Count PCB, refers to printed circuit boards with 20 or more conductive layers integrated into a single multilayer structure. These boards are designed to accommodate complex routing architectures, high-speed signal transmission, and dense power distribution networks that cannot be achieved with conventional layer counts.

High Layer PCB VS Standard Multilayer PCB

Feature	Standard Multilayer PCB	High Layer PCB
Layer Count	4 – 16 layers	20 – 60+ layers
Primary Driver	Routing density	Signal integrity + power distribution + system integration
Typical Thickness	0.8mm – 2.4mm	2.0mm – 8.0mm+
Key Process Challenges	Standard lamination	Tight registration, high aspect ratio plating, back drilling
Material Requirements	Standard FR-4	High-Tg, low-loss, high-speed materials
Typical Applications	Consumer electronics, automotive	Telecom infrastructure, servers, aerospace

High Layer PCB

High Layer PCB Manufacturing Capabilities

General Specifications

Feature	Capability
Layer Count	Up to 60 layers (evaluation required for designs > 30 layers)
PCB Thickness	0.5mm – 8.0mm (evaluation required for thickness > 6.5mm)
Max. Panel Size	Up to 21″ × 33″ (533mm × 838mm) for 2–20 layers; evaluation required for larger formats
Board Dimension	Length ≤ 1000mm; evaluation required if short side > 21 inches

Circuit Features

Feature	Capability
Min. Trace / Spacing	0.075mm / 0.075mm (75μm / 75μm) for standard designs; 0.065mm / 0.065mm (65μm / 65μm) for fine-line requirements
Copper Weight (Finished)	18μm – 140μm (0.5oz – 4oz); heavier copper available for power distribution layers
Impedance Control	±5% (tight tolerance ±3% available upon evaluation)
Controlled Dielectric Thickness	Supported for precise impedance matching

Drilling & Via Technologies

Feature	Capability
Min. Mechanical Drilling	0.15mm
Min. Laser Drilling	0.075mm (3 mil) for microvia structures (when combined with HDI features)
Aspect Ratio	Max 14:1 (evaluation required for aspect ratios > 12:1)
Back Drilling	Supported for high-speed signal integrity; removes unused via stubs
Via Types	Through-hole via, blind via, buried via, staggered via
Via Fill	Conductive epoxy, non-conductive epoxy, or copper-plated fill

Materials

Material Type	Capability
Standard Materials	FR-4, High-Tg FR-4 (Tg 170°C – 180°C)
High-Speed / Low-Loss	Panasonic Megtron 4/6/7, Isola I-Tera MT40, ITEQ IT-968, Rogers RO4000 series
Halogen-Free	Available for environmentally sensitive applications
Hybrid Stack-ups	Combination of FR-4 and high-speed materials optimized for cost and performance
High-Thermal Reliability	Materials with high decomposition temperature (Td) for aerospace/defense applications

Layer Stack-up & Registration

Feature	Capability
Layer-to-Layer Registration	±0.05mm (50μm) for standard designs; tighter tolerances available upon evaluation
Sequential Lamination	Supported for complex stack-ups requiring multiple lamination cycles
Symmetric Stack-up Design	Recommended to prevent warpage in high layer count constructions
Buried Capacitance	Embedded thin-film dielectric layers for power distribution decoupling

Surface Finishes

Feature	Capability
Standard Finishes	ENIG (Electroless Nickel Immersion Gold), OSP, Immersion Silver, Immersion Tin
High-Reliability Finishes	ENEPIG (Electroless Nickel Electroless Palladium Immersion Gold), Electrolytic Hard Gold
Selective Finishes	Mixed finishes available per design requirements

Solder Mask

Feature	Capability
Solder Mask Type	Liquid photo-imageable (LPI), high-temperature resistant for lead-free assembly
Min. Solder Mask Bridge	4 mil (green, ≤1OZ); 5 mil (other colors, ≤1OZ)
Color Options	Green, blue, red, black, white, yellow, purple (custom colors available)

Testing & Quality Assurance

Feature	Capability
Electrical Testing	Flying probe, fixture-based testing; 100% testing available
Impedance Testing	TDR (Time Domain Reflectometer) testing for controlled impedance verification
Micro-section Analysis	In-house cross-sectioning for plating thickness, layer alignment, and via integrity
Thermal Reliability	Thermal cycling, TCT (Thermal Cycling Test), HAST (Highly Accelerated Stress Test)
AOI (Automated Optical Inspection)	100% AOI for inner layers and outer layers
X-Ray Inspection	For buried via alignment and multi-layer registration verification
UL Certification	UL 94 V-0 recognized

Key Applications

Market	Applications
Telecommunications Infrastructure	Base station backplanes, core network switches, radio access network (RAN) equipment
Data Centers & High-Performance Computing	Server motherboards, storage backplanes, high-speed switch fabrics
Aerospace & Defense	Avionics computers, radar signal processing, mission computers, flight control systems
Industrial Control	Large-scale automation controllers, power distribution systems, industrial backplanes
Medical Equipment	High-end imaging systems (MRI, CT scanners), diagnostic equipment
Test & Measurement	High-speed test fixtures, semiconductor test equipment

High Layer PCB Technology Highlights

Technology	Description
Back Drilling	Removes unused via stubs that cause signal reflections and impedance discontinuities in high-speed designs
Controlled Impedance	Precise control of trace geometry and dielectric thickness to achieve target impedance values (50Ω, 90Ω, 100Ω, etc.)
Sequential Lamination	Multiple lamination cycles enabling complex stack-ups with buried and blind vias
High Aspect Ratio Plating	Specialized plating processes for thick boards with aspect ratios up to 14:1
Hybrid Material Stack-ups	Combination of standard FR-4 and high-speed materials to balance performance and cost
Signal Integrity Optimization	Layer stack-up design optimized for high-speed signal routing with dedicated power/ground planes

Application Scene

Our products are widely used in telecommunications infrastructure, data centers and high-performance computing, aerospace and defense, industrial control, medical equipment, and test and measurement.