1. Visão geral do produto
No campo de interconexão de alta densidade (IDH) Placas de circuito impresso, o12-layer 2+N+2 board represents an important direction in advanced PCB manufacturing technology. UGPCB's12-layer 2+N+2 HDI board uses ISOLA high-performance substrate material, with a finished board thickness of 2.0 milímetros, 1 oz copper on both outer and inner layers, a minimum via diameter of 0.1 milímetros, line width/spacing of 0.1 milímetros, BGA pad diameter of 0.15 milímetros, and electroless nickel/immersion gold (CONCORDAR) acabamento superficial.
Esse12-camada PCB is a typical high-density interconnect placa multicamadas suitable for electronic products with demanding requirements for signal integrity, routing density, e confiabilidade. Como um2+N+2 structure Placa IDH, it features two buildup layers on each side, with N core layers in the middle, supporting stacked or staggered microvia structures.
2. Definição do Produto
2.1 What Is a 2+N+2 HDI Board?
UM2+N+2 HDI board is a high-density interconnect printed circuit board manufactured using a sequential lamination process. O “2” in its name represents two buildup layers on each side, enquanto “N” represents the number of core layers in the middle. For this product, the total layer count is 12, meaning a 2+8+2 structure — two buildup layers on each side and eight core layers in the middle.
EssePCB HDI belongs to Type III (as defined by IPC-2226), a commonly used HDI stackup solution supporting medium pin-count, BGA de alta densidade componente roteamento. O2+N+2 PCB stackup design significantly improves routing density, supports successful routing of ultra-fine-pitch BGAs with pitches as small as 0.4 milímetros, reduces overall layer count, and minimizes signal attenuation.
2.2 Applicable International Standards
O projeto, fabricação, and acceptance of this product strictly comply with the following IPC international standards:
- IPC-6012F -Especificação de qualificação e desempenho para placas impressas rígidas: This is the internationally recognized performance specification for rigid printed circuit boards, covering the entire process from material selection to finished product, including quality indicators, qualification, and performance requirements for each process step.
- IPC-2221C -Padrão genérico para design de placas impressas: This is the foundation design standard for all documents in the IPC-2220 series, establishing generic requirements for printed board design.
- IPC-4101E -Especificação de materiais básicos para placas impressas rígidas e multicamadas: This specification covers requirements for base materials (laminate or prepreg) used primarily for rigid or multilayer printed boards.
3. Diretrizes de projeto
3.1 2+N+2 Stackup Structure Design
O12-layer 2+N+2 PCB stackup design follows the core design principles for HDI boards:
- Priority on ground planes: Ground planes are prioritized because they transmit signals in microstrip configurations.
- Low impedance and low noise: A ground-plane-based 12-layer Projeto de PCB achieves low ground impedance and low noise.
- High-speed signal routing: Intermediate layers between planes are used for high-speed signal traces, with tight coupling between signal layers.
- Adjacent plane and signal layers: Plane layers and signal layers should be placed on adjacent layers.
- Tight plane coupling: Large-area power and ground planes should be tightly coupled together.
3.2 Signal Integrity Design
Por IPC-2221C, impedance tolerance and conductor layer isolation areas are critical considerations in design de PCB de alta velocidade. Para o12-layer 2+N+2 HDI board, special attention should be paid to:
- Controle de impedância: Com 1 onças de cobre (aproximadamente 35 μm) on both outer and inner layers, precise line width/spacing control is required to achieve target impedance.
- Microvia structure: O 0.1 mm minimum via diameter falls within the microvia category (≤ 0.15 mm as defined by IPC-2221 and IPC-6012).
- BGA breakout: O 0.15 mm BGA pad combined with 0.1 mm line width/spacing supports successful breakout for 0.4 mm pitch BGAs.
4. Princípios Operacionais
O12-layer 2+N+2 HDI board operates based on the interconnection and signal transmission of multiple conductive layers. Its core operating mechanisms include:
4.1 Signal Transmission Paths
HDI boards achieve interlayer electrical connections through the following via types:
- Vias cegas: Connect from an outer layer to a specific inner layer without penetrating the entire board thickness.
- Vias enterradas: Exist only between inner layers.
- Stacked microvias: Multiple microvias stacked vertically to form a path through multiple buildup layers.
4.2 Power Distribution and Grounding
The power distribution network (PDN) do12-camada PCB is optimized through:
- Large-area power planes tightly coupled with ground planes, forming effective decoupling capacitance.
- Ground layers serving as return paths for signals, reducing loop inductance.
- Signal layers tightly coupled with adjacent plane layers, reducing electromagnetic interference (EMI).
5. Aplicativos primários e casos de uso
5.1 Target Application Areas
O12-layer 2+N+2 HDI board, with its high-density interconnect capability and excellent electrical performance, is primarily used in the following areas:
| Área de Aplicação | Typical Products | Requisitos principais |
|---|---|---|
| 5Infraestrutura G | 5Estações base G, UAA, RRU | High frequency, alta velocidade, baixa perda |
| Centros de dados | Servidores, interruptores, dispositivos de armazenamento | High-speed data transmission, alta confiabilidade |
| Computação de alto desempenho | Cartões aceleradores de IA, HPC | High-density BGA, integridade do sinal |
| Wired/Wireless Communications | Optical modules, roteadores, microwave equipment | High-frequency performance, low insertion loss |
| Eletrônica Automotiva | ADAS, radar automotivo (77 GHz) | Alta confiabilidade, temperature resistance |
| Aeroespacial e Defesa | Aviônica, sistemas de radar | Extreme environment reliability |
ISOLA materials such as TerraGreen® 400G are specifically suited for next-generation 5G infrastructure, data center systems, computação de alto desempenho, wired/wireless communications, and AI applications, supporting extremely high data transmission rates exceeding 100 Gb/s.
5.2 Compatible Product Types
- High-end smartphone mainboards
- Communication base station RF boards
- High-performance server backplanes
- AI training/inference accelerator cards
- High-speed optical modules
- Automotive radar sensor boards
6. Classificação do Produto
Based on standard PCB industry classification methods, este produto pode ser cientificamente categorizado da seguinte forma:
6.1 By Product Structure
Rigid board — Manufactured using rigid substrate materials (FR4/ISOLA).
6.2 Por contagem de camadas
Placa multicamadas — Featuring 12 camadas condutoras, bonded by insulating dielectric materials and interconnected through vias.
6.3 By Manufacturing Process
Placa IDH (placa de interconexão de alta densidade) — Featuring a 2+N+2 sequential lamination structure, classified as a second-order HDI board (2+C+2).
6.4 By IPC-2226 Stackup Type
Type III stackup — 2+N+2 or higher-order stacked/staggered microvia structures.
6.5 By IPC-6012 Quality Class
Available to meetAula 2 (dedicated-service electronic products) ouAula 3 (produtos eletrônicos de alta confiabilidade) requirements as per customer specifications.
7. Materiais utilizados
7.1 Substrato: ISOLA Series Materials
This product uses ISOLA high-performance copper-clad laminates. ISOLA is a leading material supplier in the high-frequency, high-speed PCB sector, with its products widely used in high-speed digital, high-frequency analog, RF/microwave, and other advanced circuit designs.
Typical properties of ISOLA materials (TerraGreen® 400G as an example):
| Propriedade | Valor típico | Método de teste |
|---|---|---|
| Temperatura de transição vítrea (Tg DSC) | 200°C | IPC-TM-650 2.4.25C |
| Temperatura de transição vítrea (Tg DMA) | 215°C | IPC-TM-650 2.4.24.4 |
| Temperatura de decomposição (Td @5% weight loss) | >380°C | IPC-TM-650 2.4.24.6 |
| Constante dielétrica (Dk) | 3.15 | IPC-TM-650 2.5.5.5 |
| Fator de dissipação (Df) | 0.0017 | IPC-TM-650 2.5.5.5 |
| Classificação de inflamabilidade UL | UL 94 V-0 | UL File E41625 |
ISOLA materials comply with IPC-4101/134 and offer the following advantages:
- Halogen-free and RoHS compliant
- Excellent CAF (conductive anodic filament) resistência
- Baixa absorção de umidade
- Withstands up to 6 reflow cycles at 260°C
- FR-4 process compatible — can be processed using standard Equipamento PCB
7.2 Folha de cobre
- Inner and outer layer copper thickness: 1 onças (aproximadamente 35 μm)
- Copper foil type: HVLP3 (ultra-low profile) or RTF (tratado reversamente) copper foil available upon request
7.3 Espessura da placa
- Espessura da placa acabada: 2.0 milímetros
8. Especificações de desempenho
8.1 Key Electrical Specifications
| Parâmetro | Especificação | Notas |
|---|---|---|
| Contagem de camadas | 12 camadas | 2+N+2 structure |
| Espessura da placa acabada | 2.0 milímetros | - |
| Espessura de cobre da camada externa | 1 onças (35 μm) | Cobre acabado |
| Espessura de cobre da camada interna | 1 onças (35 μm) | - |
| Diâmetro mínimo via | 0.1 milímetros | Laser-drilled microvia |
| Largura mínima da linha | 0.1 milímetros | - |
| Espaçamento mínimo entre linhas | 0.1 milímetros | - |
| BGA Pad Diameter | 0.15 milímetros | Suportes 0.4 mm pitch BGA |
| Acabamento superficial | CONCORDAR (Níquel eletrolítico/ouro de imersão) | IPC-4552 compliant |
8.2 Reliability Performance
Por IPC-6012F, rigid printed boards must meet the following reliability requirements:
- Electrical performance: Resistência ao isolamento, dielectric withstanding voltage, controle de impedância, etc..
- Mechanical performance: Força de casca, empenamento, estabilidade dimensional, etc..
- Environmental performance: Ciclismo térmico, teste de umidade, salt spray testing, etc..
IPC-6012F has introduced several new requirements for microvia structure reliability, including copper wrap plating, intermediate target lands, microsection evaluation, inner layer plating, and dielectric spacing and reliability issues for microvia structures.
IPC-6012F has increased the minimum copper thickness requirement for plated-through hole barrel walls — raised to 28 μm for Class 3/A (previously 25 μm).
8.3 Desempenho térmico
ISOLA materials with Tg ≥ 200°C and Td > 380°C support lead-free soldering processes and multiple reflow cycles.
9. Estrutura do Produto
O2+N+2 HDI board via structure includes:
- Laser blind vias: From outer layers (L1/L12) to Layer 3/Layer 10 (buildup section), 0.1 mm diameter
- Laser blind vias: From Layer 3/Layer 10 to inner core layers
- Mechanical through vias: Through the core section (Camadas 4-9)
- Stacked microvias: Blind vias can be stacked vertically for multi-layer connections
10. Recursos do produto
10.1 Capacidade de interconexão de alta densidade
- 0.1 MM Microvia: Support ultra-high-density routing
- 0.1 mm line width/spacing: Enable fine-line design
- 0.15 mm BGA pads: Apoiar 0.4 mm pitch ultra-fine-pitch BGAs
10.2 Excelente integridade do sinal
- ISOLA low-loss material (Df tão baixo quanto 0.0017) ensures low high-frequency signal attenuation
- 2+N+2 structure supports precise impedance control
- Ground planes tightly coupled with signal layers reduce EMI
10.3 Alta confiabilidade
- Complies with IPC-6012F Class 2/Class 3 requisitos
- ISOLA material with Tg ≥ 200°C and Td > 380°C
- ENIG surface finish provides excellent solderability and oxidation resistance
10.4 Compatibilidade de Processo
- ISOLA materials are compatible with standard FR-4 process flows
- Suporta laminação sequencial
- Allows multiple reflow cycles
11. Fluxo do Processo de Fabricação
The 12-layer 2+N+2 HDI board manufacturing process is as follows:
11.1 Core Board Manufacturing (Camadas Internas)
- Corte de materiais: Cut ISOLA substrate per MI requirements
- Inner layer circuit formation: Apply photoresist → expose → develop → etch → strip to form inner layer circuit patterns
- Camada interna AOI: Automated optical inspection to ensure circuit quality
- Brown oxide treatment: Enhance adhesion between inner layer copper and prepreg
11.2 First Lamination
- Empilhamento: Stack inner layer cores with prepreg per the stackup structure
- Laminação: Bond multiple layers into one unit under high temperature and pressure
11.3 First Drilling and Via Metallization
- Perfuração a laser: Drill 0.1 MM Microvia
- Desmear: Remove carbonized residue from laser drilling
- Via metallization: Electroless copper deposition to form conductive layer on via walls
- Panel plating: Build up copper thickness on via walls
11.4 Buildup Layer (Camada Externa) Fabricação
- Outer layer circuit formation: Repeat inner layer circuit formation process
- Outer layer AOI: Inspeção óptica automatizada
11.5 Second Lamination (se necessário)
- Secondary lamination: Multiple sequential lamination steps may be required for 2+N+2 structures
11.6 Final Finishing
- Outer layer drilling: Mechanical through-hole drilling
- Via metallization and plating: Through-hole metallization and copper build-up plating
- Outer layer circuits: Forme padrões de circuito da camada externa
- Máscara de solda: Apply solder mask ink
- Acabamento superficial: CONCORDAR (Níquel eletrolítico/ouro de imersão) — electroless nickel (3–6 μm) + ouro de imersão (0.05–0,1 μm) para IPC-4552
- Impressão de legenda: Silk-screen component designators and other markings
- Roteamento de perfil: Roteamento, Corte em V, etc..
- Teste elétrico: Sonda voadora ou teste de fixação
- Inspeção final: Visual inspection and packaging
12. Vantagens do acabamento superficial ENIG
Este produto utilizaCONCORDAR (Níquel eletrolítico/ouro de imersão) acabamento superficial, offering the following core advantages:
| Vantagem | Descrição |
|---|---|
| Excelente planicidade da superfície | Ideal for fine-pitch BGA and SMT assembly |
| Superior solderability | Supports multiple reflow cycles (3+ vezes) |
| Longa vida útil | 12+ months storage life |
| Strong oxidation resistance | Gold layer protects copper from oxidation |
| Boa condutividade elétrica | Suitable for high-frequency signal transmission |
The ENIG process chemically deposits a nickel-phosphorus alloy layer (approximately 3–6 μm thickness) and a gold layer (approximately 0.05–0.1 μm thickness) on the PCB copper surface.
13. Why Choose UGPCB’s 12-Layer 2+N+2 HDI Board?
- International standard compliance: Strictly follows IPC-6012F, IPC-2221C, IPC-4101E, e outras normas internacionais
- Garantia de material premium: Uses ISOLA high-performance substrate for high-frequency, high-speed performance
- Advanced manufacturing capability: Precision processing for 0.1 mm microvias and 0.1 mm line width/spacing
- Comprehensive quality control: Full-process quality management from incoming material inspection to final product testing
- Professional engineering support: Provides DFM (Design para fabricação) reviews and impedance design support
14. Solicite um orçamento
UGPCB is committed to providing high-qualityPCB HDI manufacturing services to customers worldwide. Whether you need a12-layer 2+N+2 HDI board or other layer counts and structures ofPCB multicamadas, oferecemos suporte técnico profissional e preços competitivos.
How to Get a Quote:
- Submit design files: Envie arquivos Gerber, arquivos de perfuração, and stackup specifications to our sales team
- Specify technical requirements: Include impedance requirements, material preferences, acabamento superficial, quantity, etc..
- Revisão de engenharia: Our engineers will perform DFM checks to ensure manufacturability
- Receive a quote: Get a competitive price and lead time quickly
Contate-nos
Send yourPCB design files to our sales email or submit an inquiry through our website. Our technical team will respond within 24 horas.
Declaração da fonte de dados
The technical data and standard information cited in this document are sourced from the following authoritative organizations:
- IPC (Associação conectando indústrias eletrônicas) —IPC-6012FEspecificação de qualificação e desempenho para placas impressas rígidas (Setembro 2023); IPC-2221CPadrão genérico para design de placas impressas (December 2023); IPC-4101EEspecificação de materiais básicos para placas impressas rígidas e multicamadas (March 2017); IPC-4552Especificação de desempenho para níquel eletrolítico/ouro de imersão (CONCORDAR) Chapeamento para placas impressas
- Grupo Isola — TerraGreen® 400G Product Data Sheet
- UL (Laboratórios de subscritores) - UL 94 V-0 Classificação inflamabilidade, UL File Number E41625
- Literatura Técnica da Indústria — HDI PCB stackup design and 2+N+2 structure technical documentation
