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High-density interconnect manufacturing

HDI PCB Manufacturing for Microvia Builds

Review laser microvias, blind and buried vias, fine-line routing, and via-in-pad requirements before quotation. EBest PCBA reviews the stack-up, drill sequence, copper geometry, and assembly requirements based on the project files.

Representative HDI build High-density interconnect PCB with fine-pitch BGA routing
High-density PCB with microvia and fine-pitch features.
Fine geometry4 / 4 milgeneral line / space reference
Laser drilling0.10 mmgeneral microvia reference
Via-in-padVIPPOconfirmed from the stack-up and design files
First response24 hinitial engineering response target

Start with the design constraint

When Should You Choose HDI for Your PCB?

HDI affects the stack-up, drilling sequence, registration, copper balance, and cost, so it should be considered before the layout is finalized.

Controlled-impedance multilayer PCB for dense electronic routing
High-density routing must be reviewed together with the stack-up, impedance, copper and assembly profile.
01

Fine-Pitch BGA Escape

Use microvias and finer geometry when through-hole fan-out consumes routing channels or blocks power and ground access.

02

Smaller Product Envelope

Reduce board area while balancing layer count, dielectric thickness, routing density, and reliability.

03

Blind or Buried Interconnect

Move selected connections between layers while controlling drill depth, target land, plating and sequential lamination requirements.

04

Via-in-Pad Requirements

Review fill, planarization, cap plating, pad size, and assembly requirements before approving the VIPPO structure for fabrication.

Construction selection

Choose the HDI Build-Up Structure Before Quotation

Each additional build-up cycle adds process time and tighter registration requirements. EBest PCBA confirms the required structure from the layer connectivity, via map, and approved stack-up.

Build-Up Structure

Required layer transitions determine the number of laser-drilling and lamination cycles. Cost and lead time depend on the final build-up structure.

Standard structures and items requiring additional review are identified before quotation.
01

1+N+1 HDI

One build-up layer on each side of the core structure for first-level microvia access and controlled BGA escape.

Stack-up review
02

2+N+2 HDI

Two build-up layers per side when routing requires additional blind-via transitions.

Engineering evaluation
03

Any-Layer HDI

Layer-to-layer microvia interconnect reviewed against registration, reliability and the complete via map.

Engineering evaluation
04

Via-in-Pad / VIPPO

Fill, planarization and cap plating reviewed with pad size, finish and assembly expectations.

Engineering evaluation

HDI Capability Review From Your Production Files

HDI PCB Manufacturing Capabilities

The values below are general manufacturing references. Final capability depends on copper weight, plating, hole depth, dielectric thickness, and registration, so the design files must be reviewed before quotation.

Review ItemGeneral ReferenceSpecial ReviewDecision Factors
Laser microvia0.10 mm general referenceStructure-specific reviewDielectric depth, aspect ratio, capture pad, fill and plating
Finished mechanical hole0.20 mm minimum reference0.15 mm requires special reviewBoard thickness, aspect ratio, plating and tolerance
Inner line width / spacing4 / 4 mil at 0.5-1 oz copper3 / 3 mil requires special reviewBase copper, finished copper, etching compensation and yield
Through-hole aspect ratioUp to 8:1 referenceUp to 10:1 requires special reviewHole diameter, board thickness and plating distribution
FR-4 layer count1-10 layer reference10-32 layers reviewed as specialHDI cycles, material system, copper balance and registration
Build-up structure1+N+1 after stack-up review2+N+2, stacked/staggered, and Any-Layer require project reviewConnectivity, drill sequence, lamination cycles and reliability target
Surface finishOSP, HASL, ENIG, immersion silver or tinENEPIG and hard-gold combinations by reviewFine-pitch assembly, wire bonding, storage and contact life
Impedance controlTarget and tolerance confirmed from the approved stack-up and coupon requirementsMaterial Dk, dielectric thickness, copper geometry and finished copper

Line width / spacing means two different dimensions: the first value is the minimum copper trace width; the second is the minimum clearance between adjacent traces. Final manufacturability and schedule are confirmed from project files.

Not sure whether your stack-up needs HDI? Send Gerber or ODB++ files, the via map, and BGA pitch. EBest PCBA will confirm which features are within standard capability and which require additional review before quotation. Check My HDI Stack-Up

HDI Manufacturing Process

HDI Manufacturing Process From Stack-Up to Final Test

The exact process depends on the approved build-up, materials, and inspection plan. Each lamination and drilling cycle is checked against the approved stack-up and via structure.

01 / FILE REVIEW

Stack-Up and Via Map

Check layer connectivity, microvia depth, target lands, copper and impedance requirements.

02 / BUILD-UP

Lamination and Laser Via

Control dielectric, laser depth, target lands and registration for each build-up cycle.

03 / COPPER

Metallization and Fill

Check via-wall plating, copper build, resin fill, planarization, and cap plating when required.

04 / FINE LINE

Imaging and Etching

Protect fine geometry, copper balance and impedance-critical routing through production.

05 / FINISH

Surface and Assembly Interface

Confirm ENIG, OSP or project-specific finish against BGA, via-in-pad and soldering needs.

06 / FINAL QC

Inspection and Test

Complete electrical, dimensional, microsection, and other required inspections before shipment.

Engineering and inspection evidence

Check HDI Risks Before Production

HDI issues often occur around capture pads, microvia plating, registration, resin fill, fine-line copper, and assembly pads. Inspection should focus on these areas before shipment. 直接删除

DFM and Stack-Up Check

Review missing inputs, drill definitions, via-to-pad geometry, copper weight and the build sequence before quotation.

Registration Control

Confirm target-land access, annular relationships and layer alignment through the sequential build-up.

Microsection Evidence

Use microsections when required to check plating, fill, interfaces, and finished hole structure.

Electrical and Impedance Test

Perform electrical testing and impedance verification against the approved data and coupon plan.

HDI PCB soldering and inspection review for dense interconnect risks
HDI PCB sample prepared for fine-pitch and registration review.

Anonymized engineering case profiles

HDI PCB Manufacturing Examples

These examples show how typical HDI requirements are reviewed before fabrication. Final stack-up, via structure, and inspection requirements depend on the actual project files.

Physical HDI PCB with fine-pitch component and BGA pad areas
CASE 01 / 1+N+1 HDI

Fine-Pitch Processor HDI

A compact processor board used microvias to create additional BGA escape channels while maintaining the required stack-up, copper, and impedance.

Typical application: compact processing modules, embedded controllers and dense computing interfaces.
Build-up
1+N+1 reference; final layer transitions follow the approved via map.
Microvia
0.10 mm general reference; dielectric depth and capture-pad geometry remain file-specific.
Key review
BGA escape, stack-up, finished copper, impedance notes and assembly interface.
Production basis
Approved stack-up, drill data, review items, and inspection plan.
Discuss This HDI Build
Physical HDI PCB production panel with repeated dense circuit modules
CASE 02 / SIGNAL INTEGRITY

Controlled-Impedance Telecom HDI

Fine-pitch routing and high-speed interfaces had to be reviewed against the actual reference planes, dielectric data and layer transitions.

Typical application: network processors, communication modules and high-speed control equipment.
Build-up
Compare 1+N+1 and 2+N+2 based on required layer transitions and routing density.
Impedance
Trace geometry, dielectric values, copper and reference planes reviewed together.
Verification
Coupon, electrical test and microsection evidence when required by the approved construction.
Production basis
Approved impedance table, stack-up, via structure, and production test plan.
Discuss This HDI Build
Physical compact high-density control PCB panel with fine component features
CASE 03 / HIGH-TG CONTROL

High-Reliability Compact Control HDI

Dense digital routing shared the board with power and I/O areas, so material selection, fine-line geometry, and the build sequence were reviewed together before fabrication.

Typical application: industrial controllers, compact instrumentation and high-temperature electronics.
Material
High-Tg FR-4 grade selected against assembly profile and operating conditions.
Geometry
Layer-specific copper and line/space limits checked before stack-up commitment.
Evidence
Registration, dimensional, and electrical records, plus any required inspection records.
Production basis
Approved fabrication data, material selection, and inspection plan.
Discuss This HDI Build

Industry applications

Common Applications for HDI PCBs

Telecommunications network equipment

Telecommunications

Network processors, RF modules and compact routing with impedance review.

Medical electronic diagnostic equipment

Medical Electronics

Portable diagnostic and monitoring products with strict documentation and reliability requirements.

Automotive electronic systems

Automotive Electronics

Compact sensing and control modules reviewed for thermal and vibration conditions.

Industrial automation and control equipment

Industrial Control

Embedded controllers and communication boards where compact size and reliable operation are required.

Prepare a quote-ready review

Send the Files Needed for an HDI PCB Quote

Gerber or ODB++ dataNC drill and laser-via filesProposed stack-upImpedance requirementsVia type and fill notesFinished copper requirementsSurface finish and assembly notesQuantity and delivery target

Send Your HDI PCB Design for Review and Quotation

Send the files you have. EBest PCBA will review the stack-up, microvia, copper, impedance, and assembly requirements before quotation and production.

FAQ

HDI PCB Manufacturing Questions

What is the difference between a blind via, buried via and microvia?
A blind via connects an outer layer to one or more inner layers. A buried via connects internal layers without reaching either outer surface. A microvia is a small blind structure commonly formed by laser. The correct structure depends on connectivity, dielectric depth, target land and the approved build sequence.
How do I choose between 1+N+1, 2+N+2 and Any-Layer HDI?
The choice follows the number of build-up layers, required layer transitions, BGA escape strategy and reliability target. Each additional build-up cycle changes cost, registration risk and inspection needs. EBest PCBA confirms the construction after reviewing the stack-up and via map.
Can EBest PCBA manufacture via-in-pad or VIPPO structures?
Yes, subject to file review. Send the pad size, via diameter, fill requirement, finished copper, surface finish and assembly expectation. The fill, planarization and cap-plating process is confirmed before quotation.
What line width and spacing can be reviewed for HDI PCB?
For 0.5-1 oz inner copper, 4/4 mil line width and spacing is a published general reference, while 3/3 mil requires engineering review. Final feasibility depends on base copper, finished copper, plating, etching compensation, board area and the complete design.
What information is needed for an HDI PCB quotation?
Send Gerber or ODB++ data, drill and laser-via files, stack-up, impedance targets, via type and fill notes, copper requirements, surface finish, dimensions, quantities and any assembly or inspection requirements. A review can begin with partial information.
How are stacked and staggered microvias evaluated?
The review considers via depth, target land, copper fill, registration, lamination sequence and reliability requirements. Do not assume one via geometry can be repeated across every layer; the final structure follows the approved stack-up and reliability requirements.
Can HDI PCB fabrication be combined with turnkey PCBA?
Yes. PCB fabrication can be connected with component sourcing, assembly, inspection and testing. Send the BOM, placement data, drawings and test expectations so via-in-pad, finish, soldering and downstream interfaces can be reviewed together.