HDI board (High Density Interconnector), also known as high-density interconnect board, is a circuit board that uses micro blind buried hole technology and has a relatively high line distribution density. The HDI board has both inner and outer circuits, which are connected internally by drilling and metallization processes.

　　HDI boards are generally manufactured using the stacking method, and the more times they are stacked, the higher the technical level of the board. Ordinary HDI boards are basically stacked once, while higher-order HDI uses two or more layers of technology, as well as advanced PCB technologies such as hole stacking, electroplating filling, and laser direct drilling.

　　When the density of PCBs increases beyond eight layers, manufacturing with HDI will result in lower costs compared to traditional complex pressing processes. HDI boards are conducive to the use of advanced assembly technology, and their electrical performance and signal accuracy are higher than traditional PCBs. In addition, HDI boards have better improvements in radio frequency interference, electromagnetic wave interference, electrostatic discharge, heat conduction, etc.

　　Electronic products are constantly developing towards high density and precision. The so-called "high" not only improves machine performance, but also reduces the size of the machine. High density integration (HDI) technology can make terminal product design more miniaturized, while meeting higher standards of electronic performance and efficiency. Currently, many popular electronic products, such as mobile phones, digital cameras, laptops, automotive electronics, etc., use HDI boards. With the upgrading of electronic products and market demand, the development of HDI boards will be very rapid.