HDI Board(High-Density Interconnect PCBs)

Detailed Explanation of HDI Manufacturing Capabilities

1. Core Technologies & Processes
   • Laser Microvia Technology:
     Employs CO₂/UV laser drilling (hole diameter 0.076–0.127mm) to replace traditional mechanical drilling, achieving 3–5mil micro blind/buried vias. Back-drilling is used to eliminate signal resonances, ensuring high-speed transmission (e.g., PCIe 6.0).
   • Stacked Structure:
     Supports 1st-order (1+N+1) to 3rd-order (3+N+3) build-up layers, controlling Z-axis expansion rates ≤2.7% (compared to 4.5% for ordinary FR-4) through sequential lamination, reducing the risk of hole copper cracking. Multi-layer stacked via designs (e.g., blind vias stacking from layer 1→2→3) are employed above 2nd-order to avoid copper plating challenges caused by cross-layer blind vias.
   • Material Innovations:
     Substrates utilize ultra-low loss dielectrics (Megtron6/TU-862HF) and RCC (Resin Coated Copper) copper foils (without glass fiber layers) to enhance laser drilling efficiency and circuit etching precision.
2. Key Performance Indicators
   • Routing Density: Minimum line width/spacing of 2/2 mils (0.05mm), supporting BGA pitches ≤0.4mm.
   • Via Copper Reliability: Average blind via copper thickness ≥18μm (single point ≥12μm), passing 288℃ PCT (Pressure Cooker Test) and CAF (Conductive Anodic Filament) resistance certification (100V/85℃/85%RH).
   • Impedance Control: Tolerance of ±10% (for ≥50Ω signals), suitable for 56Gbps+ high-speed scenarios.
3. Application Scenarios & Trends
   • High-End Applications:
     • AI Servers/Optical Modules: Boards with 48+ layers, combined with embedded copper coin technology for optimized thermal dissipation.
     • Automotive Electronics: High Tg materials (Tg≥180℃) compatible with temperature variations from -55℃ to 150℃.
   • Technological Evolution:
     Progressing towards Any-layer HDI and Hybrid Laminate structures, combined with automated inspection (AOI+ET) to enhance yield rates.

   • 		HDI PCB Technics Capacity
     No.	Item	Description	DataSheet
     1	Material	Brand	SY、ITEQ 、KB、NOUYA
     2	HDI Construction		1+N+1、2+N+2、3+N+3、4+N+4、5+N+5、6+N+6、Anylayer
     3	Construction order		N+N、N+X+N、1+(N+X+N)+1
     4	Layer		6-48Layers
     5	Min Pattern Width/Spacing	Unit:mil	2/2
     6	Min Mechanical Hole	Unit:mm	0.15mm
     7	Min Thickness of Core Board	Unit:mil	2mil
     8	Laser Hole	Unit:mm	0.075mm-0.1mm
     9	Min thickness of PP	Unit:mil	2mil
     10	Max diameter of resin plug hole	Unit:mm	0.4mm
     11	Electroplating to fill holes		Can do it.
     12	Electroplating to fill holes size	Unit:mil	3-5mil
     13	hole pile pad/hole pile hole/pad hole(VOP)	mil	Can do it.
     14	The distance from the wall of via hole to the pattern	mil	7mil
     15	Laser drilling hole accuracy	mil	0.025mm
     16	Min BGA pad center distance	mil	0.3mm
     17	Min SMT	mil	0.25mm
     18	Plating hole-filling sag	mil	≤10um
     19	Back drilled/countersink hole tolerance	mil	±0.05mm
     20	Through-hole plating penetration capacity	Rate	16:1
     21	Blind hole plating penetration capacity	Rate	1.2:1
     22	BGA min PAD	Unit:mil	0.2
     23	Min Buried Hole(Mechanical Hole)	Unit:mil	0.2
     24	Min Buried Hole(Laser Hole)	Unit:mil	0.1
     25	Min Blind Hole(Laser Hole)	Unit:mil	0.1
     26	Min Blind Hole(Mechanical Hole)	Unit:mil	0.2
     27	Minimum spacing between laser blind hole and mechanical buried hole	Unit:mil	0.2
     28	Min Laser Hole	Unit:mil	0. 10(depth≤55um)、0. 13(depth≤100um)
     29	MinBGA pad center distance	Unit:mil	0.3
     30	Interlaminar alignment	Unit:mil	±0.05mm(±0.002")

      

   • Comprehensive Analysis of 2025 HDI PCB Advanced Manufacturing Processes (Technological Innovations in High-Density Interconnect PCB Production)

     A detailed breakdown of the 6 core manufacturing processes for 2025 HDI PCBs, covering any-layer stacked via technology, AI-powered quality inspection systems, and green material selection to meet miniaturization demands for 5G smartphones, AR/VR devices, and more. Provides high-precision PCB production solutions.

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     1. Intelligent Design & Substrate Selection (DFM 4.0)

     • AI-Collaborative Design:
       • Integrates Cadence Allegro and Ansys SIwave tools to enable automatic routing for 10μm line/space widths, avoiding impedance discontinuities (±5% tolerance), and supporting 20-layer any-layer stacked via structures.
     • Material Innovation:

       Substrate Type	Characteristics	Application Scenario
       Ultra-Thin Core (≤0.05mm)	Dk=3.3±0.05, Df=0.002@10GHz	Foldable smartphone motherboards
       Halogen-Free PP Sheets	Glass transition temperature (Tg) ≥180℃, CTE ≤40ppm/℃	EU environmental compliance products

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     2. Inner Layer Precision Machining (Tolerance ≤±1.5μm)

     • Laser Direct Imaging (LDI):
       • Uses 405nm wavelength laser to achieve 30μm line width etching precision, improving yield by 12% compared to traditional exposure methods.
     • Plasma Etching Technology:
       • Employs Cl₂/O₂ mixed gas to etch copper layers, controlling sidewall undercut to 20° and improving impedance uniformity to 98%.
     • Nano-Scale Brown Oxide Process:
       • Copper oxide microstructure height of 0.8μm, bonding strength ≥1.5N/mm (IPC TM-650 2.4.8 standard).

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     3. Lamination & Microvia Interconnect Technology Breakthroughs

     • Any-Layer Stacked Via Process:

       Technology Type	Via Structure	Space-Saving Rate
       1st-Order HDI	Blind vias + through-holes	25%
       Any-Layer HDI (3+N+3)	Laser stacked vias + copper-filled plating	55%

     • Vacuum Pressing Control:
       • Segmented temperature ramp (80℃→180℃/60min), pressure 0.8–1.2MPa, void rate <0.3%.

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     4. Outer Layer Patterning & Surface Finishes

     • mSAP (Modified Semi-Additive Process):
       • Electroless copper plating (1μm) + pattern plating (15μm) achieves 8μm line width precision, reducing costs by 18% compared to subtractive methods.
     • High-Frequency Surface Finish Solutions:

       Finish	Characteristics	Application Scenario
       ENEPIG	Ni layer 2μm, Au layer 0.03μm	0.25mm pitch BGA
       Immersion Silver + OSP	Thickness 0.15μm, soldering life ≥5 reflow cycles (J-STD-020 standard)	Consumer electronics

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     5. Intelligent Inspection & Reliability Verification

     • 3D X-Ray + AI Algorithm:
       • Detects stacked via alignment deviations (≤10μm), copper-filled voids (≤5μm), with a defect detection rate of 99.7%.
     • Extreme Environment Testing:

       Test Item	Condition	Acceptance Criteria
       High-Temperature/High-Humidity Storage	85℃/85%RH/1000h	Impedance drift <3%
       Thermal Shock Cycling	-55℃↔125℃/1000 cycles	No microcracks, delamination

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     6. Green Manufacturing & Cost Optimization

     • Cyanide-Free Electroplating Process:
       • Uses citric acid-based copper plating, reducing wastewater COD by 85%, compliant with EU REACH 2025 regulations.
     • AI-Optimized Panelization Design:
       • Achieves substrate utilization ≥92%, reducing 10-layer HDI board production costs by 22% compared to 2023.

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     Industry Cases & Data Support

     • Flagship Smartphone Motherboard:
       • Adopts 18-layer any-layer HDI (board thickness 0.6mm), integrating 25,000 interconnect points, achieving signal loss <0.1dB/mm@28GHz, with a yield of 95.3%.
     • Automotive Radar Module:
       • 77GHz mmWave PCB uses hybrid stack-up (Rogers 4835 + FR-4), optimizing temperature drift coefficient to 5ppm/℃, reducing mass production costs by 30%.