Restriction of Hazardous
Substances Directive

Though often referred to as the lead-free directive, RoHS is not limited in scope to lead alone. RoHS also restricts the use of these six substances:

  • Lead (Pb)
  • Mercury (Hg)
  • Cadmium (Cd)
  • Hexavalent Chromium (Cr6+)
  • Polybrominated Biphenyls (PBB)
  • Polybrominated diphenyl ether (PBDE)

Sunstone has several RoHS-compliant products, to fit just about every project:

Product & ServiceValue Proto
PCBexpressPCBpro 
Custom Quote
Lead-Free PCB Material  RoHS- compliant FR-4RoHS-compliantFR-4RoHS-compliantFR-4Many options
Surface FinishesImmersion Silver
 Immersion SilverImmersion Silver, ENIGImmersion Silver, ENIG,
Hard gold, Lead Free Solder, and OSP
 Quote & Order
Quote & Order
Quote & OrderQuote & Order

RoHS does not require any specific product labeling. Many manufacturers have adopted their own compliance marks to reduce confusion.

Visual indicators in use include:

  • "RoHS compliant" labels
  • Green leaves
  • Check marks
  • "PB-Free"
  • WEEE trash-can logo with an "X" over the can
  • Lower case "e" within a circle with arrows (Chinese)

RoHS helps reduce damage to people and the environment in third-world countries where much of today's "high-tech trash" ends up. The use of lead-free solders and components has provided immediate health benefits to electronics industry workers in prototype and manufacturing operations. Solder paste no longer represents the same health risk it did before RoHS implementation.*

RoHs and Immersion Silver Frequently Asked Questions

  • Why choose silver immersion over other RoHS-compliant options?

    We are convinced that immersion silver is the best RoHS compliant finish for the majority of our customers and their applications. Our testing has shown that silver gives the best solder joint of any of the other finishes tested.

    Silver immersion plating has been on the market for 10 years and end users have benefitted from this finish long before RoHS requirements came into play. Silver, when stored properly, has a shelf life of 12 months (easily as long as OSP), and can withstand multiple heat cycles during assembly. Silver immersion does not require any special fluxes or solders and fits in perfectly with the “quick turn” mode of operation.

    The contact resistance is very low (see chart) and the co-planarity of the finish provides a completely flat surface for solder paste application on fine pitch devices. The silver immersion finish is easily electrical tested without damage or “puncture” of the surface of the silver plating.

    We have found that the Immersion Silver plating process is not limited to just a “post mask” finish, but can be applied to boards prior to mask and can also be processed through nickel/gold tab operations without any adhesion complications. When we process an Immersion Silver plating order, we not only give our customers the best finish (in our opinion) but, for complete RoHS compliance and assembly needs, we put this finish on high Tg, high Td and low CTE material; all at no extra cost.

     

  • Do our RoHS boards cost more?

    Sunstone offers flexibility for you to choose your board finish, our immersion silver plating is available with all our services at NO ADDITIONAL COST.

  • What are the temperature requirements for lead-free processing (material, etc)?

    The temperature is dependent on the soldering profile of the lead free solder used. This is usually about 30 °C higher than standard tin/lead solder (peak temperatures of 250 °C opposed to 220 °C for tin/lead). The material we use for our RoHS compliance boards are built to withstand these higher temperatures. Solderability of silver immersion boards (Can I use lead solder on silver boards and what temperature needs to be used) Our RoHS compliant silver immersion finished boards can be soldered with standard tin/lead solder at standard tin/lead temperatures or using RoHS compliant solder at the higher no lead soldering temperatures.

  • Is the board performance affected with RoHS processing?

    Although we cannot address new RoHS compliant components, the characteristics of the material used in building the RoHS compliant laminate do not vary significantly from laminate that is less temperature resistant; therefore we would not expect a significant change in the performance of the board.

  • What is the thickness of Immersion Silver plating?

    4 – 12 micro inches.

  • How do I order RoHS boards?

    On our web site, choose silver finish instead of tin/lead and we will automatically build those boards on high temperature resistant RoHS compliant.

  • Do we have UL approved RoHS boards?

    Yes

  • What is the purity of the silver immersion we use?

    The purity of silver is 90%+

  • What is the shelf life of our Immersion Silver RoHS boards?

    If the wrapped packages are stored at less than 35 °C and 85% R.H. then there is a shelf life of 12 months. If boards are unpackaged and unused, then they should be re-packaged.

  • What are our material thickness limitations?

    0.062 standard thickness for all board orders, including Quickturn PCB Prototype boards. For Full Feature printed circuit board design orders other than 0.062”, please call for availability. 

  • Can I make multi-layer RoHS boards?

    Yes