Printed Circuit Boards have long been standard in computers and other electronics, but as time has moved forward the devices people use have gotten increasingly smaller, and at the same time they continue to showcase greater capabilities. As much as this has simplified the lives of many, the shrinking computer phenomenon has been far from simple. Much of the credit for the development of these various small electronic devices lies with High Density Interconnect Printed Circuit Boards (HDI PCB).
Shrinking Technology in a Big Way
What allows an HDI PCB to be so much smaller than a conventional PCB is that the wiring is far denser per unit area. This method of production makes these components smaller and lighter even as the devices they are installed in perform increasingly better by layering tiny microvias that have holes less than 150 micro millimeters and buried vias within lamination and insulation materials. As HDI PCB manufacturing methods have evolved over time they have utilized impedance control and improved their high frequency transmission capabilities in order to lessen the amount of radiation they exude, making them safer to use.
Developing Standards
Like many things in technology, HDI PCB technology has moved fast, and engineers from all over the world have gotten in on the game. While the average person thinks of their cell phone or maybe their tablet computer when they hear of this technology, it actually has a far wider reach expanding into the medical industry, defense, and aerospace in addition to the commercial capabilities that bring products such as mp3 players and gaming consoles. There was a lot of confusion at first, because the high density integrated PCBs were being called by several different names. America and European countries named the smaller circuit boards Sequence Build Up (SBU), while the Japanese used the abbreviation BUM for Build Up Multilayer Board and referred to the technology as MVP, MicroVia Process.
To bring continuity to the technology, the IPC Printed Circuit Association used their industry watchdog muscle to declare a HDI PCB as the industry accepted name for the technology and smaller circuit boards.

While setting industry standards was an important step to reduce confusion and allow for increased advancements, things still aren't always clear. Often different companies are involved in the design, assembly and distribution of HDI PCBs and similar products leaving more room for error the more frequently the technology changes hands. Many smaller technology companies have not been able to hold their own by embracing their subspecialties, but larger companies that are able to take the process from start to finish and stand by their work are leading more people, businesses, and the government to expect excellence.