RoHS and Lead-Free Process
We offer fully RoHS compliant processes and services to support our customer's lead-free manufacturing needs. In addition, we offer solutions to our customers with products needing to make the transition from tin-lead manufacturing to RoHS compliant manufacturing.
The following are reference links to sites with lead-free information in the electronics industry:
• IPC Lead Free - IPC's lead free information web site
• Pb-Free.com - "The data source for Pb-Free electronics assembly"
The following are reference links regarding Lead-Free in the electronics industry:
• Lead-Free Magazine - Online publication focused on lead free
Using Lead-Free Components with Current SN-PB Processes
As many of the component manufacturers have converted their component surface platings to lead-free alternatives, the question of whether these components can be used on existing tin-lead products has become very common.
The simple answer is "yes," but with a few very important exceptions! Components which carry their own lead-free solder joints, such as BGAs and MicroSMDs, must be attached using lead-free processes. Because the solder for these types of components is lead-free, the higher temperature processes must be used in order to form reliable solder joints. Also creating an exception are some of the new lead-free finishes being considered by the component industry; these finishes, however, are not in common use yet.
For the majority of components being converted to lead-free, the platings used as a replacement for SN-PB are compatible with existing tin-lead processes. The most common lead-free platings are matte tin, silver palladium, and nickel-palladium-gold. These finishes have been in use for years (matte tin was the original plating decades ago; silver palladium is a common finish on SMT caps and resistors; nickel-palladium-gold has been common on ICs for over 10 years) and have reliable tin-lead processing histories. The component manufacturers are aware that their products must be compatible with both lead based and lead-free soldering processes and have been choosing finishes which offer this compatibility.
New finishes are being researched and tested which are not compatible with current tin-lead processes. At some point in the future these finishes will probably become common as tin-lead assembly processes are phased out. Because these non-backward compatible finishes are being considered by the component manufacturing industry, it is possible for them to be in use now. For this reason, it is important that component finishes be reviewed for backward compatibility when a lead-free device is specified to be placed on a tin-lead circuit.
The following are links to some manufacturers' sites regarding lead-free plating and compatibility with tin-lead processes:
• Cypress Semiconductor's "Qualification Report of Nickel/Palladium/Gold-Finish for
• National Semiconductor's " Impact to Customers " page
• National Semiconductor's "Lead-Free Q & A" page, question #19 "Are the lead-free parts backwards compatible with SnPb solder processes?"
• Texas Instruments' "Lead (Pb)-Free F.A.Q", question #15 "Are TI Pb-Free parts compatible with a Pb-based soldering process?"
• ST Micro's "Application Note on Soldering Compatibility"
• NIC's "Components reference table on backwards compatibility"
• Atmel's "bulletin on backwards compatibility"