Electronic products are constantly developing towards high density and high precision. The so-called "high" not only improves the performance of the machine, but also reduces the volume of the machine. High-density integration (HDI) technology can enable more miniaturized end-product designs while meeting higher standards for electronic performance and efficiency. Many of the current popular electronic products, such as mobile phones, digital cameras, notebook computers, and automotive electronics, use HDI boards. With the upgrading of electronic products and market demand, the development of HDI boards will be very rapid.
What is HDI board?
HDI board (High Density Interconnector), that is, high-density interconnect board, is a circuit board with relatively high circuit distribution density using micro-blind buried hole technology. The HDI board has an inner layer circuit and an outer layer circuit, and then uses processes such as drilling and metallization in the hole to realize the internal connection of each layer of circuits.
HDI boards are generally manufactured by lamination method. The more times of lamination, the higher the technical grade of the board. Ordinary HDI boards are basically one-time build-up, and high-end HDI uses two or more build-up technologies, and at the same time adopts advanced PCB technologies such as stacked holes, electroplating and filling holes, and laser direct drilling. When the density of PCB increases to more than eight layers, the cost of HDI manufacturing will be lower than the traditional and complicated lamination process.
The electrical performance and signal accuracy of HDI boards are higher than those of traditional PCBs. In addition, HDI boards have better improvements in radio frequency interference, electromagnetic wave interference, electrostatic discharge, and heat conduction. High-density integration (HDI) technology can enable more miniaturized end-product designs while meeting higher standards for electronic performance and efficiency.
The HDI board uses blind hole plating and then performs secondary lamination, which is divided into first-order, second-order, third-order, fourth-order, and fifth-order. The first-order is relatively simple, and the process and process are easy to control. The main problems of the second order, one is the alignment problem, and the other is the problem of drilling and copper plating. There are many second-order designs. One is that the positions of each stage are staggered, and when the next adjacent layer needs to be connected, it is connected through a wire in the middle layer. The method is equivalent to two first-order HDIs. The second is that two first-order holes overlap, and the second-order is realized by superposition. The processing is also similar to the two-order, but there are many process points that need to be specially controlled, which is the above mentioned. The third is to punch holes directly from the outer layer to the third layer (or N-2 layer). The process is much different from the previous one, and the difficulty of punching is also greater. For the third order, it is analo to the second order.
PCB, the Chinese name is printed circuit board, also known as printed circuit board, is an important electronic component, a support for electronic components, and a carrier for electrical connections of electronic components. Ordinary PCB boards are mainly FR-4, which is made of epoxy resin and electronic grade glass cloth.
