High density interconnects (HDI) PCB, represent one of the fastest-growing technologies in PCBs. Because of its higher circuitry density than traditional circuit boards, the HDI PCB design can incorporate smaller vias and capture pads, and higher connection pad densities. HDI Boards contain blind and buried vias and often contain micro vias of 0.006inch or less in diameter.

By using HDI technology, designers now can place more components on both sides of the raw PCB if desired. Now as the development of via in pad and blind via technology, it allows designers to place smaller components closer together. This means faster transmission of signals and a significant reduction in signal loss and crossing delays. HDI PCB is frequently found in mobile phones, touch-screen devices, laptop computers, digital cameras, 4G network communications, also prominently featured in medical devices.

HDI PCB microsection

6Layer HDI pcb microsection

Compare to standard Rigid PCB, HDI PCB request much higher wiring density with finer trace and spacing, smaller vias and higher connection pad density. Blind and buried vias' design is one of their marked feature. HDI PCB are widely used for Cell Phone, tablet computer, digital camera, GPS, LCD module and other different area.

The advantages of HDI PCB include:

Reduce the cost

Better reliability

Increase the wiring density

Increase design efficiency

Can improve the thermal properties

In favor of the use of advanced packaging technology

Has better electrical performance and signal correctness

Can improve the radio frequency interference, electromagnetic interference and electrostatic discharge

Currently the advanced HDI technology we used include: "Copper Filled" for special stack microvia, "Laser Direct Imaging"(LDI) is specifically designed for fine line technology, to eliminate dimensional stability problem of artwork caused by environmental and material issues. "Direct Laser Drill"(DLD) is drilling of copper layer by direct CO2 laser irradiation, compare to additional laser drilling with conformal mask, the copper direct laser drilling is capable of providing higher accuracy, better hole quality and better efficiency for HDI projects

General Specification for HDI PCB

Layer Count: 4-20Layers

Type of stack up: 1+N+1, 2+N+2

Stand Process Flow for 1+4+1 HDI PCB: /uploadfile/upload/file/20210401/20210401090238_50253.pdf

Material Available: FR4, High Tg FR4, Halogen Free FR4

Board thickness: 0.4-3.2mm

Finished copper thickness: 1/3oz – 3oz

Min trace width/spacing: 3/3mil

Min through hole: 0.2mm

Min blind via: 0.1mm

Surface treatment: Immersion Gold, ENIG + OSP

6 Layer HDI PCB for SSD Memory ----------- 8 Layer HDI PCB board

6 Layer HDI PCB for SSD Memory                                         8 Layer HDI PCB board

Material: FR4 S1000-2                                                            Material: FR4 TU-768

Layer count: 6                                                                          Layer count: 8

Board thickness: 1.6mm                                                          Board thickness: 2.0mm

Copper thickness: 1oz                                                             Copper thickness: inner 0.5oz/outer 1oz

Surface finish: ENIG                                                                Surface finish: ENIG

Min. hole: 6mil                                                                          Min. Hole: 0.2mm

Min. Line/space: 3.9/3.9mil                                                       Min Line/space: 4.1/4.1mil

Usage: SSD Memory Card                                                       Usage: Data collection