By Joseph Fjelstad, Verdant Electronics
One year after the electronics industry was forced to bow to legislative pressure of the EU’s RoHS legislation banning the use of lead in electronic solder in July 2006, a solderless assembly process was introduced in response. The standout process, named in honor of the 14th century English monk and logician, William of Occam, was unveiled by Verdant Electronics. The announcement was greeted both with skepticism and concern by some on the supply side and with a great deal excitement and interest by many on the product side, especially given near universal frustration with the ban, especially given the uncertainty of the reliability of lead free, the cost of conversion and the chaffing facts that 1) no evidence of risk from lead in electronic solder was ever produced and 2) that the US EPA had produced a full life cycle analysis of solders indicating that traditional tin-lead solder was more environmentally friendly than the SAC alloys that were replacing them.
In the ensuing year, while the electronics industry has been reeling from the effects of tin prices that have quadrupled since 2001 and copper prices that have doubled and the cost of oil now exceeds $130 a barrel, slow but steady efforts have been underway at locations around the globe to breathe life into the Occam solderless assembly concept. Reliability test vehicles and demonstration assemblies are being fabricated on at least four continents. Given the simplicity of the concept which can be easily be accomplished by an electronics hobbyist at home, it comes with little surprise.
A significant amount of interest in solderless assembly (or solder-free assembly as some individuals are beginning to call it) has been expressed by the military and aerospace industry. Members of this community are exempt from the EU RoHS mandate but they are finding that they are not unaffected by the new law. One of the big concerns is getting parts with a tin-lead finish, especially BGAs.
Their frustration stems from the fact that the finish on such parts has been converted to lead-free, unfortunately without changing over any of the part numbers. Their other big concerns are reliability, especially though shock and vibration and the return of tin whiskers a problem that was solved by tin-lead solder. While there has been no wholesale adoption of the concept (reliability studies must necessarily be complete before hand) interest is growing among military and aerospace providers. There is, for example, presently a research project sponsored by the military that is seeking “solderless” assembly solutions for electronic products. In addition, there are a number of “closed door” projects underway at a number of companies who are seeking to prove and exploit the benefits of solderless assembly for their own and others purposes.
Verdant Electronics has also been active and has recently aligned itself with the TPL Group to help develop partnerships that will accelerate the Occam concept’s movement into the market place. Presently there are early negotiations with some household name companies to identify a n number of projects of mutual benefit.
However, the ultimate beneficiaries of any soldlerless or solder-free technology will surely be the consumer and the environment. The reduction in materials and energy use that are hallmark aspects of the process, however, equally important is the fact that Occam assemblies could prove to be the most reliable electronic assemblies on the market. Verdant Electronics has playfully suggested redefining electronics assembly testing to go from “drop testing” to “throw testing” as a standard reliability test method. Along the same line, Occam demonstration assemblies fabricated by Promex Industries in Santa Clara, CA have also inadvertently proven their reliability in some unexpected ways as aerospace electronics engineer, Mike Green found out when he reported that his demonstration assembly (which included an integral battery) went through a complete washing and drying cycle when assembly fell in with a load of laundry and came out continuing to operate. Such an event bodes well for the concept.
In summary, in the year since the announcement there has been a lot of activity on solderless technology with a number of projects underway or in the works. The terms “all copper assembly” and solderless and solder-free are showing up with increasing frequency and it is likely that the pace of such terms showing up in literature and in the market place is likely to quicken. And while, skeptics continue to “shoot arrows” at the Occam concept progress is being made. Given the many advantages of soldlerless/solder-free assembly have compared with lead-free including: near automatic RoHS compliance, obviation of expensive and energy intensive processing and improved reliability, it seems likely that they will find their place in the realm of electronics assembly technologies.