By John H. Lau
McGraw Hill
16 Chapters, 585 pages plus
exhaustive references for each chapter
Another great book from the kitchen table of John Lau. Mr. Lau always acknowledges his wife and family in the foreword of his books. His daughter, I believe, has also contributed to book illustrations in the past‹what a team approach!
I have not had much practical experience with flip chip technology in the past. Recently, I have been involved with a couple of hands-on process projects. Flip chip is an interesting technology, and there is much to learn. Like Mr. Lau1s previous textbooks, there is a lot to be learned from each of the chapters, particularly the alternative bumping techniques. I feel sure that anyone can easily justify the book1s cost.
The chapters cover each of the major steps in the process and, of course, the economics of the process, as compared to other well-known chip on board techniques. The text is detailed and very easy to read and understand for a beginner. The formulae in some of the sections are a little heavy, but each of the chapters is well illustrated, which makes the book very understandable and enjoyable.
As one reads through the chapters, it1s easy to see the many contributions that IBM has made to flip chip technology. IBM was practicing this technology in the 1960s and, for some reason, many companies have taken over three decades to consider the use of this technology. The chapters on underfill materials are very useful and Mr. Lau helps the reader understand the materials and their applications.
The problems of moisture in solder mask, on the basic board, did not seem to be addressed. Moisture has been shown to cause voiding in underfills during curing and final cure. Selecting the correct materials can reduce the problem.
Chapter 16 covers failure analysis, a subject dear to my heart, and this practical look at techniques used to find the root cause of failures is well illustrated with practical examples. As with any new processes, insight into the ways to reduce false starts is an asset.
A detailed chapter on the assembly process, as a whole, is missing from this book. Such a chapter would have made the use of flip chip still more approachable to engineers.