High Density Interconnect Board
High density interconnect board or HDI board is one of the fastest growing technologies in PCB industry. HDI boards contain blind and/or buried vias and often contain microvias of .006 or less in diameter. They have a higher circuitry density than traditional circuit boards.
There are 6 different types of HDI boards, through vias from surface to surface, with buried vias and through vias, two or more HDI layer with through vias, passive substrate with no electrical connection, coreless construction using layer pairs and alternate constructions of coreless constructions using layer pairs.
HDI technology is the leading reason for electronic products transformation like camera, mobile, computer, pad, etc. Products do more, weigh less and are physically smaller. Specialty equipment, mini-components and thinner materials have allowed for electronics to shrink in size while expanding technology, quality and speed.
As consumer demands change, so must technology. By using HDI technology, designers now have the option to place more components on both sides of the raw PCB. Decreased component size and pitch allow for more I/O in smaller geometries. This means faster transmission of signals and a significant reduction in signal loss and crossing delays.
While some consumer products shrink down in size, its quality remains at its best level. Using HDI technology is possible to reduce an 8 layer through-hole PCB to a 4 layer HDI microvia technology packed PCB. The wiring capabilities of a well-designed HDI 4 layer PCB can achieve the same or better functions as that of a standard 8 layer PCB. Although the microvia process increases the cost of the HDI PCB, the proper design and reduction in layer count reduces cost in material square inches and layer count more significantly.