Broad sense: printed circuit boards are equipped with resistors, capacitors, IC and other electronic components, and the products are electrically connected by soldering. Generally we also call it as PCBA.

Because copper is easy to oxidize in air, the oxide layer of copper has a great influence on soldering. It is easy to form false welding and false welding. In serious cases, it will cause the pad and components cannot be welded. Therefore, PCB will have a process in manufacturing, coating (plating) on the pad surface to protect the pad from being oxidized.

In the design, layout is an important link. The result of layout will directly affect the effect of wiring, so it can be considered that reasonable layout is the first step of PCB design success.

printed circuit boards are one of the important electronic components in the electronic industry. Almost every electronic device, from electronic watches, calculators, computers, communication electronic devices, military weapon systems, as long as there are integrated circuits and other electronic components, in order to interconnect them, printed circuit boards are used.

In PCB design, wiring is an important step to complete product design. It can be said that the preparation work is done for it. In the whole PCB, the design process of wiring is the highest, the skills are the finest and the workload is the largest.

Circuit boards, also known as printed circuit boards or PCB, can be found in every electronic device in the world today.

HDI is the abbreviation for high-density interconnector. It refer to a technology for manufacturing printed circuit boards (PCB). Based on traditional multi-layer printed circuit board manufacturing technology, HDI introduces a new process of foil-RCC (Resin Coated Copper) laminate, supplemented by laser drilling, horizontal/vertical PTH (Plated through Hole) wet process and other processes produced by the blind hole/multi-layer buried PCB circuit boards.

Printed circuit boards, are providers of electrical connections for electronic components. PCB is used in almost all electronic devices, so it is called

According to the analysis of Zhanxin PCB Industry Research Institute, the market size of PCB in mainland China will increase from 27.1 billion US dollars in 2016 to 32.9 billion US dollars in 2018. 2017 and 2018 are the golden years of PCB development in China, with growth rates of 9.62% and 10.08% respectively.

As the leader of A-share PCB, Avary holdings released its semi annual report on August 13, which showed that due to the Sino US trade war and the shrinking demand for downstream electronic products, its main business decreased slightly but remained stable, with a year-on-year increase in net profit of about 40%.

With the increasing demand for the volume of information products, especially the development of mobile device products in the direction of continuous miniaturization, such as the current popular ultra book products, even new wearable intelligent devices, must use HDI high-density interconnection technology to make the carrier board, and further reduce the size of the terminal design.

Nowadays, high density interconnect (HDI) printed circuit board is widely used. Traditional HDI circuit board is used in portable products and semiconductor packaging products. This paper will focus on the third type of application of HDI: high-speed industrial system application, which is used in telecommunication and computer systems. The difference between these two types of PCB lies in the large size of PCB, the focus on electrical performance, and the challenge of conductor lies in the very complex packaging of PBGA and CCGA.