By John H Lau and Ricky Lee
McGraw Hill
560 pages, 12 chapters,
illustrations and photographs
Lau and Lee have produced another timely textbook for the printed circuit board (PCB) industry, and it will useful for PCB design and fabrication engineers alike. The use of microvias of different styles has been growing in the industry for the last few years with many new techniques being used to fabricate ever-smaller connections. The team behind the relatively new Professional Engineering Series from McGraw Hill should be congratulated on yet another strong title.
The new text is not exclusively for the PCB fabrication engineer as its title may suggest; it covers via technology for board- and component-level interconnection. Increasingly, ball grid arrays (BGAs) and chip-scale packages (CSP) use microvias to make interconnection between the PCB and silicon possible. The first chapter sets the scene with industry trends and the ever-decreasing feature sizes demanded in professional consumer products.
In Chapter 3, Lau and Lee cover manufacturing, design and reliability aspects of each of the major via types, including drilled, laser ablation and photo vias. The text also provides good coverage of the basic PCB fabrication process and where changes may be necessary for different via manufacturing techniques. Of particular interest are the changes in base substrates necessary with laser vias.
As with many textbooks today, a chapter of this book relates to alternative solders, „Solders for the Next Generation.‰ A hot issue for engineers today is alternatives to lead-based alloys, which this chapter covers from a solder alloy prospective and from the effect on area array packages such as BGAs and wafer-level chip-scale packages (WLCSPs).
Chapter 11 covers the assembly process for flip chip and CSP onto the base substrate and features a number of issues relating to underfill. It illustrates some of the mechanical and electrical faults that occur after environmental testing and also illustrates visual defects and those that can only be found during x-ray or C scan.
This book is a good, strong reference, well illustrated with line drawings, micrographs and product examples.