Issue link: https://iconnect007.uberflip.com/i/898297
8 The PCB Magazine • November 2017 There is no denying that high-density inter- connect (HDI) has been around a long time— over 25 years, believe it or not. From almost the moment of its conception in the U.S., the tech- nology was adopted by and used almost exclu- sively in Asia. It was a puzzlement—and a frus- tration—as to why the quick move to Asia, and why the U.S. did not pick up on this technolo- gy and start making these boards. However, Tai- wan, et al., were making most of the consum- er products such as cellphones and camcorders, and HDI helped pack the necessary computing power into these devices. But HDI is back! In this month's reader sur- vey, we learned that while half of the respon- dents have less than 25% of their production in HDI boards, for some 28% it accounts for more than half their business, and a for a third of those, HDI is their main technology (Ques- tion 1). In addition, 30% of all respondents ex- pected their percentage of HDI work to grow to at least 25% and 45% expected it to represent more than half their business (Question 2). According to our respondents, the three main industry segments using HDI were tele- communications, automotive and consumer electronics. We then asked about market trends: What market trends are driving your HDI work? Obviously, a multi-answer question, but note that many of the answers have to do with den- sity on the board (Question 3). Now, think back 25 years and you real- ize that fine features on a PCB were certain- ly not the same as they are now, and neither were the chip packages being used. Drilling, im- aging and other PCB processes have made sig- nificant advances as you can imagine. And to- day's densely-packed semiconductor packages are making HDI a necessity for many types of boards for many more applications—think elec- tronics in cars, medical electronics and your in- credible smartphone—all making use of com- ponents with many, many more I/Os and finer pitches (imagine what Moore's Law has done in 25 years!). How to fit all those connections into a finite area on a PCB? So, it's with all this in mind that we delve into this month's issue on HDI, which is not for the faint of heart or the light reader! Of course, we can't talk about HDI without first hearing from the acknowledged "Father of HDI," Happy Holden. And Happy has put togeth- er our intro article on the subject. He provides the proverbial wakeup we need to move all the faster into it. He points out concerns and obstacles and what needs to be done to overcome them. Continuing in this theme, Mike Carano, RBP Chemical Technology, discusses in his col- by Patty Goldman I-CONNECT007 HDI: Born in the USA and Making a Comeback PATTY'S PERSPECTIVE 0 - 25% 26 - 50% 51 - 75% 76 - 100% What percentage of the PCBs you design/build are HDI technology? Q1: 56% 9% 16% 19% PERCENTAGE OF HDI PERCENTAGE OF RESPONDENTS Source: I-Connect007 Research 0 - 25% 26 - 50% 51 - 75% 76 - 100% What percentage of your boards do you expect to be HDI in three years? Q2: 30% 16% 25% 29% PERCENTAGE OF HDI PERCENTAGE OF RESPONDENTS Source: I-Connect007 Research