Here HDI is the abbreviation of High Density Interconnect. HDI PCB is a PCB with higher wiring density than traditional printed circuit boards. HDI technology enables a denser design on the PCB and thus more traces and/or components in a given area can be laid out.
HDI PCBs use blind and/or buried vias, micro vias, vias in pads or a combination of two or more of them, and pack more components into a smaller area through very thin traces. All HDI PCBs should comply with IPC-2226 – Sectional Design Standard for High Density Interconnect (HDI) Printed Boards. IPC-2226 divides HDI into types I to VI depending on usage and complexity.
The most common applications for HDI technology are computer, mobile phone components, medical equipment, network communications, military communication equipment, automotive and aerospace industries. And as the increasing demands for smaller and faster products, HDI techniques will likely play a more important role.
X-Parts HDI PCBs Manufacturing Capabilities
| Features | Standard | Advanced |
| Layer Count | 4-22L | 30L |
| Technology Highlights | Multi-layer boards with a higher connection pad density than standard boards, with finer lines/spaces, smaller via holes and capture pads allowing micro-vias to only penetrate select layers and also be placed in surface pads. | |
| HDI Builds | 1+N+1, 2+N+2, 3+N+3, 4+N+4, Any Layer | |
| Materials | FR4 Standard, FR4 High Performance, Halogen Free FR4, Rogers | |
| Copper Thickness | 18 μm – 70 μm | |
| Minimum Track / Spacing | 0.075 MM / 0.075 MM | |
| PCB Thickness | 0.4 MM – 3.2 MM | |
| Maximum Dimensions | 610 MM x 450 MM | |
| Surface Finish | ENIG, Immersion Tin, Immersion Silver, Electrolytic Gold, Gold Fingers | |
| Minimum Mechanical Drill | 0.15 MM | |
| Minimum Laser Drill | 0.10 MM | 0.075 MM |