HDI is the English abbreviation of High Density Interconnector. High Density Interconnection (HDI) manufacturing printed circuit board is a structural component formed by insulating materials and conductor wiring. When the printed circuit board is made into the final product, it will be installed with integrated circuits, transistors (triodes, diodes), passive components (such as resistors, capacitors, connectors, etc.) and other various electronic parts. By means of wire connection, electronic signal connection and proper function can be formed. Therefore, the printed circuit board is a platform to provide component connection, which is used to receive the base of connecting parts.
Because PCB is not a general terminal product, the definition of its name is somewhat confused. For example, the motherboard used for personal computers is called the motherboard and cannot be directly called the circuit board. Although there are circuit boards in the motherboard, they are not the same. Therefore, when evaluating the industry, they are not the same. For another example, because there are integrated circuit parts loaded on the circuit board, the news media call it an integrated circuit board (IC board), but in essence it is not equivalent to a printed circuit board.
On the premise that electronic products tend to be multi-functional and complex, the contact distance of integrated circuit components will be reduced, and the speed of signal transmission will be relatively improved. The following will be the increase in the number of wiring, and the local reduction in the length of inter-point wiring, which requires the application of high-density wiring configuration and micropore technology to achieve the goal. Wiring and bridging are basically difficult to achieve for single-sided and double-sided boards, so the circuit board will tend to be multi-layer, and due to the continuous increase of signal lines, more power layers and ground layers are necessary means of design, all of which make multi-layer printed circuit board more common.
For the electrical requirements of high-speed signals, the circuit board must provide impedance control with AC characteristics, high-frequency transmission capability, and reduce unnecessary radiation (EMI). With the structure of Stripline and Microstrip, multi-layer design becomes necessary. In order to reduce the quality problem of signal transmission, insulating materials with low dielectric coefficient and low attenuation rate will be used. In order to match the miniaturization and array of electronic components, the circuit board will also continuously increase its density to meet the demand. The appearance of BGA (Ball Grid Array), CSP (Chip Scale Package), DCA (Direct Chip Attachment) and other group parts assembly methods has promoted the printed circuit board to an unprecedented high-density level.
The holes with diameter less than 150um are called microvias in the industry. The circuit made by using the geometric structure technology of this microhole can improve the efficiency of assembly, space utilization, and so on. At the same time, it is also necessary for the miniaturization of electronic products.
For circuit board products with this structure, the industry has used many different names to refer to such circuit boards. For example, European and American companies used to call this kind of product SBU (Sequence Build Up Process), which is generally translated as 'Sequence Build Up Process', because the process they produced is in a sequential construction mode. As for Japanese manufacturers, because the pore structure produced by such products is much smaller than the previous ones, the manufacturing technology of such products is called MVP (Micro Via Process), which is generally translated as 'Micro Via Process'. Some people also call this kind of circuit board BUM (Build Up Multilayer Board) because the traditional multilayer board is called MLB (Multilayer Board), which is generally translated as 'multiplayer board'.
In order to avoid confusion, the IPC Circuit Board Association of the United States proposed to call this kind of product technology HDI (High Density Interconnection) technology. If translated directly, it will become high-density interconnection technology. However, this cannot reflect the characteristics of the circuit board, so most circuit board manufacturers call this kind of product HDI board or the full Chinese name 'high-density interconnection technology'. However, due to the smoothness of spoken language, some people directly call such products 'high-density circuit boards' or HDI boards.
HDI application
Electronic design is trying to reduce its size while continuously improving the performance of the whole machine. From mobile phones to small portable products of smart weapons, 'small' is the eternal pursuit. High-density integration (HDI) technology can make the design of terminal products more compact, while meeting higher standards of electronic performance and efficiency. HDI is widely used in mobile phones, digital cameras, MP3, MP4, laptops, automotive electronics and other digital products, among which mobile phones are the most widely used. HDI boards are generally manufactured by build-up method. The more times of build-up, the higher the technical level of the board. The ordinary HDI board is basically one time lamination. High-order HDI uses two or more times lamination technology, and at the same time uses advanced PCB technologies such as hole stacking, electroplating hole filling, laser direct drilling, etc. High-level HDI boards are mainly used in 3G mobile phones, advanced digital cameras, IC carrier boards, etc.
Development prospect: According to the purpose of the high-level HDI board -- 3G board or IC carrier board, its future growth is very rapid: in the next few years, the growth of 3G mobile phones in the world will exceed 30%, and China will soon issue 3G licenses; Prismark, an IC board industry consultancy, predicts that China's growth rate from 2005 to 2010 is 80%, which represents the technical development direction of PCB.
Market supply and demand analysis
The continuous growth of mobile phone production is driving the demand growth of HDI board. China plays an important role in the world mobile phone manufacturing industry. Since Motorola fully adopted HDI boards to manufacture mobile phones in 2002, more than 90% of mobile phone mainboards have adopted HDI boards. The research report released by the market research company In-Stat in 2006 predicted that the global mobile phone production will still grow at a rate of about 15% in the next five years. By 2011, the total global mobile phone sales will reach 2 billion.
The production capacity of domestic HDI boards can not meet the rapidly growing demand. In recent years, the global production status of HDI mobile phone boards has undergone major changes. The major PCB manufacturers in Europe and the United States, apart from the well-known mobile phone board manufacturers ASPOCOM and AT&S, still supply Nokia with second-grade HDI mobile phone boards, most of the HDI production capacity has been transferred from Europe to Asia. Asia, especially China, has become the main supplier of HDI boards in the world. According to Prismark's statistics, China's mobile phone production accounted for about 35% of the global total in 2006. It is estimated that by 2009, China's mobile phone production will reach 50% of the global total, and the purchase of HDI mobile phone boards will reach 12.5 billion yuan. From the perspective of major manufacturers, the existing capacity of major domestic manufacturers is less than 2% of the global total demand. Although some manufacturers have invested to expand production, overall, the capacity growth of domestic HDI still cannot meet the demand of rapid growth.
HDI circuit advantages
It can reduce the cost of PCB: when the density of PCB increases more than eight layers, the cost of HDI manufacturing will be lower than that of traditional complex pressing process.
Increase circuit density: interconnection of traditional circuit boards and parts
It is conducive to the use of advanced construction technology
Better electrical performance and signal correctness
Better reliability
Improves thermal properties
Can improve radio frequency interference/electromagnetic wave interference/electrostatic discharge (RFI/EMI/ESD)
Increase design efficiency