We have been supporting one of our large customers’ engineering operations by producing lead-free prototypes in our San Diego NPI center since January 2004. Our sister operation, Total Electronics, has assembled a lead-free implementation team which includes a staff engineer with a Ph.D. in this aspect of materials sciences. They have currently have the capability of producing lead-free surface mount assemblies and are planning to transition their first customer program to lead-free in Q2 2005.

While there are a number of considerations in the move to lead-free electronics, some of the most important are:

  • Lead-free reflow and wave soldering temperatures are significantly higher than for tin-lead products. Because of this, many existing parts are not compatible with lead-free production unless they are moved to a manual assembly process.
  • Many components are not yet available in lead-free packaging. For these two reasons, it is virtually a requirement to re-design any product that is moving to lead-free. In doing this, it is an opportune time to move to 100% SMT packaging (or at least limit through-hole technology to intrusive reflow). We are prepared to work with our customers to re-design their products to fit into the lead-free environment.
  • Some component manufacturers are not changing part numbers when they transition to lead-free materials. This will make tracking very difficult. We, and the IPC, are encouraging all suppliers to change part numbers. Either way, our customers will need to make significant changes in their AVLs. We are prepared to assist in this effort and have strong partnerships with our supplier-partners in this area.
  • Lead-free products may have a grainy solder appearance normally associated with cold solder joints in the past. There are likely to be more voids and opens with lead-free soldering, and more exposed copper on pads. The IPC is releasing new standards for quality for lead-free products. Our teams will continue to stay abreast of new standards development.

In Europe, the Restriction of the use of certain Hazardous Substances in electrical and electronic equipment (RoHS) states:

"Beginning 1 July, 2006, new electrical and electronic equipment put on the market shall not contain lead, mercury, cadmium, hexavalent chromium, polybrominated biphenyls (PBB) or polybrominated diphenyl ethers (PBDE)."

There is some debate as to whether lead-free solder joints are less reliable in large temperature ranges. For this reason, it appears that the automotive, medical (implanted and infected products), IT/Telecommunications servers, large scale stationary industrial tools and aerospace/military sectors will initially be exempt from the July, 2006 European mandate. Spare parts are exempt. The requirement is placed on any company selling products under their name into Europe and it should be noted that hazardous substance restrictions go beyond elimination of lead alone. In addition, there is a similar requirement already in existence in Japan.

The overall price premium for lead-free SMT assemblies is between 5% and 10%; and somewhat higher for through-hole assemblies. However, by re-designing products simultaneously, it is likely that the price premium can be avoided or at least reduced.

Currently, we have customers wishing to take surface mount products to lead-free in 2005, and we are supporting those efforts. Generally, our customers are re-designing their products as they make this move and usually working to eliminate wave soldering requirements.