Handbook of Lead‐Free Soldering Technology for Microelectronic Assemblies

Citation

Willis, B. (2005), "Handbook of Lead‐Free Soldering Technology for Microelectronic Assemblies", Microelectronics International, Vol. 22 No. 1, pp. 54-54. https://doi.org/10.1108/mi.2005.22.1.54.1

There are now six books relating to lead‐free technology produced by researchers and users alike. All the books provide an ideal first source of information to the user in a structured manner, and in most cases better than the Web. Jennie Hwang also has a new title due for launch this year to complement her previous Electrochemical Publication title. It will be interesting to see how many more hit the streets between now and 2006.

All in all this new title from the IBM partnership, Puttlitz and Stalter is the best volume currently available with a good mixture of theory and practical lead‐free information. It is strongly recommended as an addition to your bookshelf as there are lots of practical issues covered often overlooked by others.

Many process engineers may jump directly to the process sections as these provide an insight into all the firsthand experience of Panasonic, IBM, Universal and Philips. Try and avoid missing some of the other great sections but it is inevitable that techies will cherrypick some sections. On the whole, components is the major issue and then wave soldering during the lead‐free conversion process. A good deal of experience is provided here on wave issues and feedback on possible prevention of fillet lifting, changes to contamination monitoring, new protection for stainless steel erosion and machine design changes. These include separation distance between waves, positive cooling after the wave and board support.

It is fair to say that Japanese suppliers have made more innovative machine changes based on their practical experience. Vitronics Soltec have gained considerable process experience over the last few years and have very effectively presented their data to industry creating a leading brand name throughout Europe and USA.

The re‐development of the reflow process by companies in Japan is interesting. It is fair to say that the reflow technology previously used was not up to date with equipment in Europe and the US. With the need for higher temperatures and better controls considerable development has been undertaken to improved Delta T capability for lead‐free. Although not mentioned in the text it is known that some companies are using vapour phase for very demanding boards.

Reliability engineers will be happy with the amount of information and the number of good references for more research. Details are provided on the alloys, their performance, potential reliability and cost implications for the end user.

Tin whiskers has a section all of its own and describes in detail the potential problems of whisker growth. It outlines the current thinking and suggested solutions in what is still a bewildering phenomena. The section is well illustrated but still demonstrates how little we really know and how much information conflicts with practical experience.

I guess the only criticism on the book would be the alignment of some of the tables and illustrations. There are many sections where the body text on the page does not relate to the position of the figures which can be annoying to the reader. As stated earlier this is the textbook you should have and the publisher Marcel Dekker should be more aggressive in its marketing and bring it to the attention of more engineers.