6-Layer 2+N+2 HDI PCB with ITEQ IT150 Material | Communication‑Grade High‑Density Interconnect Board

Produktübersicht

UGPCB stellt die vor 6‑layer 2+N+2 HDI PCB (Modell: 6L 2+N+2 HDI-Leiterplatte). This high‑density interconnect Leiterplatte is engineered specifically for communication equipment. It uses ITEQ IT150 high‑performance laminate, combined with a second‑order HDI build‑up architecture, 2.5mil/2.5mil fine‑line trace and space, Und 0.1mm laser microvias. These features deliver reliable interconnections for 5G base stations, high‑speed network switches, optische Module, und ähnliche Anwendungen.

Im Leiterplatte Industrie, HDI (Hochdichteverbindung) technology is the core enabler for shrinking component pitches and rising signal speeds. Der 2+N+2 HDI PCB architecture represents the second‑order HDI category. It achieves an optimal balance among routing density, Signalintegrität, und Herstellungskosten.

What Is a 2+N+2 HDI PCB?

Definition and Nomenclature

“2+N+2” is a standardized naming convention for HDI stack‑up structures. It is defined in theIPC-2226 standard and is classified asTyp III within that system.

Breaking down the term:

• Der first “2” means two sequential build‑up layers above the core.
• “N” stands for the number of core layers (here N=2, d.h., two inner core layers).
• Der second “2” means two sequential build‑up layers below the core.

Daher, a 2+N+2 structure adds two build‑up layers on each side of the conventional core. These are constructed throughtwo sequential lamination cycles. This 6‑layer board therefore comprises: 2 outer build‑up layers + 2 inner core layers + 2 outer build‑up layers.

HDI-Klassifizierung gemäß IPC-2226

The IPC‑2226 standard defines several HDI types based on microvia structures and build‑up layer counts:

HDI-Typ	Struktur	Build‑up Layers (pro Seite)	Minimum BGA Pitch	Typische Anwendungen
Typ I	1+N+1	1 Schicht	0.5mm	Smartphones, mid‑density designs
Type II/III	2+N+2	2 Schichten	0.4mm	Networking -Geräte, high‑performance computing
Typ III / Ausflüssig	3+N+3 and above	3+ Schichten	0.3mm and below	Flaggschiff-Smartphones, AI modules

This product falls into the2+N+2 category. It features two build‑up layers per side, with microvias that can be arranged in eitherstacked or staggered Konfigurationen.

Grundlegende technische Spezifikationen

Parameter	Spezifikation
Modell	6L 2+N+2 HDI-Leiterplatte
Material	ITEQ IT150
Schichtzahl	6 Schichten (2+N+2 second‑order HDI)
Farbe der Lötmaske	Black or White (optional)
Dicke der fertigen Platte	1.0mm
Kupferdicke der inneren Schicht	1 OZ (~35μm)
Kupferdicke der äußeren Schicht	0.5 OZ (~17.5μm)
Minimale Spur / Abstand	2.5Mil / 2.5Mil (~63.5μm / ~63.5μm)
Minimum Mechanical Drill	0.2mm
Minimum Laser Drill	0.1mm
Oberflächenbeschaffung	Immersionsgold + OSP
Primäre Anwendung	Kommunikationsausrüstung

Material Deep Dive: ITEQ IT150

Material Positioning

ITEQ IT150 ist ein medium‑Tg, halogen‑free, multifunctional epoxy laminieren. It sits between standard FR-4 and high‑performance low‑loss materials. It delivers lead‑free process compatibility, good manufacturability, and cost‑effectiveness.

The IT150GS variant (within the IT150 family) is a medium‑Tg (Tg >150° C durch DSC), halogen‑free, middle‑loss material. It offers high thermal reliability and excellent CAF resistance. It is specifically designed for server, Lagerung, and networking applications.

Schlüsselleistungsparameter

Based on ITEQ official datasheets and IPC‑TM‑650 test methods:

Eigentum	Testmethode	Typischer Wert	Einheit
Glasübergangstemperatur (Tg)	DSC (IPC‑2.4.25)	155	°C
Zersetzungstemperatur (Td, 5% Gewichtsverlust)	TGA (IPC‑2.4.24.6)	365	°C
CTE der Z-Achse (A1, unter Tg)	IPC‑2.4.24	35–40	ppm/° C.
CTE der Z-Achse (A2, über Tg)	IPC‑2.4.24	220–240	ppm/° C.
X/Y‑axis CTE (40–125°C)	IPC‑2.4.41	11/13	ppm/° C.
Dielektrizitätskonstante (Dk) @ 1GHz	IPC‑2.5.5.13	4.2–4,5	-
Dissipationsfaktor (Df) @ 1GHz	IPC‑2.5.5.13	0.010–0.018	-
T288 Thermal Stress	IPC-TM-650	>60	Minutes
Feuchtigkeitsabsorption	IPC‑2.6.2.1	0.12	%
Entflammbarkeitsbewertung	Ul94	V-0	Bewertung
UL MOT (Max Operating Temp)	-	130	°C

Materialvorteile

1. Lead‑Free Process Compatibility
Standard FR‑4 typically has a Tg around 130°C. ITEQ IT150 delivers155°C. Under lead‑free reflow peaks of260°C, this higher Tg provides superior dimensional stability. The material resists excessive Z‑axis expansion, which significantly reduces the risk of via barrel cracking and pad lifting during assembly.

2. Ausgezeichneter CAF -Widerstand
CAF (Leitfähiges anodisches Filament) is a primary failure mode in PCBs. It occurs when electrochemical migration creates short circuits under humid and hot conditions. ITEQ IT150 offershigh CAF resistance (18L / less than 100mil). This makes it especially suitable for long‑term outdoor deployment in communication infrastructure.

3. Halogen‑Free Compliance
ITEQ IT150 meetsJPCA‑ES‑01‑2003 halogen‑free standards. Chlorine (Cl) und Brom (Br) content are each below 0.09% nach Gewicht. Total Cl+Br is below 0.15% (1500ppm).

Entwurfsrichtlinien

Stack‑Up Architecture

The 2+N+2 HDI PCB is manufactured throughsequential lamination:

1. Core fabrication – Start with a double‑sided copper‑clad laminate. Etch inner layer circuits, perform mechanical drilling (0.2mm), and plate to create buried via connections.
2. First build‑up – Apply prepreg and copper foil (or RCC) to both sides of the core. Execute the first lamination cycle.
3. First laser drilling – Drill first‑order blind vias (laser holes at 0.1mm) and fill them with copper.
4. Second build‑up – Apply additional dielectric layers and copper foil. Execute the second lamination cycle.
5. Second laser drilling – Drill second‑order blind vias (0.1mm) and fill with copper.
6. Outer layer circuits – Form outer layer circuits (trace/space 2.5mil) and apply the surface finish.

Dastwo‑sequential‑lamination process is precisely what the “2” in 2+N+2 signifies.

Fine‑Line Circuit Design

Dieses Produkt erreicht 2.5Tausend/2,5 Mio. (~63.5μm/63.5μm) Spurbreite und -abstand. This exceeds the HDI-Design Level C (60‑99μm) defined in IPC‑2226. This fine‑line capability enables:

• 0.4mm pitch BGA breakout with ample routing channels.
• Flexible signal routing for high‑density Komponente Platzierung.
• Reduced layer count, which lowers overall PCB cost.

Microvia -Technologie

Dieses Produkt verwendet ahybrid drilling approach:

• Mechanisches Bohren – Minimum diameter 0.2mm, used for through‑holes and buried vias in the core.
• Laserbohrung – Minimum diameter 0.1mm (4Mil) , used for blind vias in build‑up layers.

The 0.1mm laser microvia reduces via area by75% compared to a 0.2mm mechanical hole. This significantly frees up routing space. It is fundamental to achieving high‑density interconnect and enablingvia-in-pad designs for fine‑pitch BGAs.

Funktionsprinzip

The 2+N+2 HDI PCB works through amulti‑layer interconnect architecture:

1. Core‑layer interconnection – Buried vias, formed by mechanisches Bohren + Überzug, connect signals between core layers.
2. Build‑up interconnection – Blind vias, formed by Laserbohrung + Überzug, connect outer signal layers to inner layers.
3. Full‑board through‑holes – After stack‑up completion, mechanical drilling penetrates all layers to create through‑holes.
4. Signal transmission path – High‑speed signals travel from surface BGA pads → through laser blind vias into inner layers → across buried vias through the core → through laser blind vias on the opposite side to the bottom layer.

Dasstepped interconnect structure shortens signal paths and reduces parasitic via effects. Infolge, it preserves high‑speed signal integrity.

Leistungsvorteile

Thermische Zuverlässigkeit

ITEQ IT150’sTd (decomposition temperature) reaches 365°C, which is well above the lead‑free reflow peak of 260°C. T288 thermal stress testingexceeds 60 Minuten without delamination. This ensures material integrity through multiple reflow cycles.

Signalintegrität

Bei 1 GHz, ITEQ IT150 exhibits a dielectric constant Dk of approximately 4.2–4.5 and a dissipation factor Df of 0.010–0.018. As a “standard‑to‑mid‑loss” material, IT150 provides a compelling price‑performance ratio compared to ultra‑low‑loss materials. This makes it ideal for production‑ready communication equipment.

Mechanische Stärke

ITEQ IT150 deliversflexural strength of 470–500 N/mm² in the warp direction and 400–430 N/mm² in the fill direction. This ensures structural integrity throughout assembly and field deployment.

Produktklassifizierung

This product is classified across multiple dimensions:

Classification System	Kategorie
IPC‑2226 HDI Type	Type II/III (2+N+2, double build‑up per side)
HDI Order	Second‑order (2 laser drilling cycles + 2 lamination cycles)
Rigid/Flexible	Starre PCB
Schichtzahl	6‑Lagen-Mehrschichtplatine
Materialsystem	Medium‑Tg, halogen‑free, FR‑4‑compatible epoxy
Oberflächenbeschaffung	Immersionsgold + OSP hybrid finish
Anwendungsdomäne	Communication‑grade PCB

Ablauf des Herstellungsprozesses

UGPCB follows this production sequence for the 6‑layer 2+N+2 HDI PCB:

Schritt 1: Core Layer Fabrication
Material cutting → Inner layer dry film → Etching → AOI inspection → Brown oxide treatment

Schritt 2: First Build‑Up
Laminierung (Kern + Prepreg + Kupferfolie) → First lamination → First‑order laser drilling (0.1mm) → Desmear → Electroless copper + plating → Circuit patterning

Schritt 3: Second Build‑Up
Second lamination → Second lamination → Second‑order laser drilling (0.1mm) → Desmear → Electroless copper + plating → Circuit patterning

Schritt 4: Outer Layer and Finishing
Mechanisches Bohren (0.2mm through‑holes) → Electroless copper + plating → Outer layer circuits (2.5Tausend/2,5 Mio.) → Solder mask → Immersion Gold + OSP surface finish → Electrical testing → Final inspection → Packaging and shipment

The entire process involvestwo lamination cycles and two laser drilling operations. This demands exceptional process control and precision.

Anwendungsszenarien

This product is primarily designed forKommunikationsausrüstung:

5G Kommunikationsinfrastruktur

• 5G Basisstationen (gNB) – RF front‑end and baseband processing units.
• High‑speed backplane interconnects for 5G network equipment.
• Enterprise‑grade routers and core switches.

High‑Speed Data Transmission

• 400G/800G optical modules – control and signal processing boards.
• High‑speed fiber‑optic switches.
• Optische Transceiver.

Other High‑End Applications

• High‑performance servers and storage devices.
• AI inference/training accelerator cards.
• Advanced medical imaging equipment.

The 2+N+2 HDI structure is particularly well‑suited formoderate pin‑count, high‑density BGA Routenführung. It enables complex signal interconnects within limited board space.

Warum wählen Sie UGPCB??

UGPCB brings deep manufacturing expertise to HDI PCB production:

• Fine‑line capability – 2.5mil/2.5mil trace/space in volume production, meeting advanced HDI design requirements.
• Mature microvia process – 0.1mm laser via + 0.2mm mechanical drill hybrid solution with stable yield.
• Comprehensive material certification – Full qualification on ITEQ IT150 and other mainstream material systems.
• End‑to‑end process control – Every step from cutting to electrical testing strictly follows IPC-6012 rigid PCB qualification and performance specifications.
• Communication industry track record – Extensive experience in 5G base station, optical module, and network equipment Leiterplattenherstellung.

Fordern Sie noch heute ein Angebot an

Whether you are designing high‑speed backplanes for 5G base stations or developing next‑generation optical modules, UGPCB’s 6‑layer 2+N+2 HDI PCB provides the reliable interconnect foundation your project deserves.

Datenquellendeklaration

The technical data cited in this document comes from the following authoritative standards and sources:

1. IPC-2226 - - Sectional Design Standard for High Density Interconnect (HDI) Leiterplatten
2. IPC‑6012E/F - - Qualifikations- und Leistungsspezifikation für starre Leiterplatten
3. IPC/JPCA‑2315 - - Design Guide for High Density Interconnect Structures and Microvias
4. ITEQ IT‑150 / IT‑150GS Official Datasheets and Material Specifications
5. IPC-TM-650 – Test Methods Manual (including methods 2.4.4, 2.4.24, 2.4.24.6, 2.4.25, 2.5.5.13, 2.6.2.1, und andere)
6. JPCA‑ES‑01‑2003 - - Halogen‑Free Copper‑Clad Laminate Standard
7. Ul94 - - Norm zur Sicherheit und Entflammbarkeit von Kunststoffmaterialien für Teile in Geräten und Geräten