High Density Interconnect (HDI)

Overview

High-density interconnect (HDI) PCBs further develop upon this foundation, utilizing microvias, fine-line routing, blind and buried vias, and via-in-pad designs to achieve tighter component placement and high-speed performance within a compact size.

 

Applications

HDI PCB (High Density Interconnect PCB) is mainly used in compact, high-performance electronic products. Typical application fields include:

Consumer, Computer & Networking, Automotive, Medical.

 

Specifications

Feature	Capability	Feature	Capability
Via Types	Blind via, buried via, through-hole via	Min. mechanical drilling	0.15mm
Number of layers	Up to 60 layers (evaluation required above 30 layers)	Min. laser drilling	Standard 4 mil, 3 mil require evaluation (corresponding to single 106PP).
HDI builds	1+N+1, 2+N+2, ... , 6+N+6(≥6 orders require evaluation)	Max. laser drilling	8 mil (corresponding dielectric thickness cannot exceed 0.15mm)
Copper weights( finished)	18um-70um	Min. controlled depth drilling	PTH: 0.15mm; NPTH: 0.25mm
Min trace/spacing	0.065mm/0.065mm	Aspect ratio	Max 14:1; evaluate if greater.
PCB thickness	0.1-8.0mm (evaluation required for less than 0.2mm or greater than 6.5mm)	Min. solder mask bridge	4mil(green, ≤1OZ)
Max. PCB dimension(finished)	2-20 layers, 21*33 inches; length ≤ 1000mm; evaluate if short side > 21 inches		5mil(other colors, ≤1OZ)
		Diameter range of resin-filled vias	0.254-6.5mm

 

Competitive Advantage

HDI PCB stack-up structures provide designers with greater flexibility in layer allocation, component placement, and routing options, enabling efficient utilization of available space and optimization of the PCB layout. The common HDI PCB stack-up structures are shown in the left diagram.