Manufacturing Issues of RoHS Implementation

The availability of RoHS materials, components, and manufacturing processes has become a big issue. Still, electronics industry could not find the real replacements to non-RoHS materials. Many RoHS alternatives are being used by manufacturers, but there are standardizations in usage of materials or manufacturing processes.

Reliability Issues of RoHS Materials & RoHS Manufacturing

Unproven RoHS Alternates. It is already seven years completed after RoHS initiation. But still, electronics industry could not find proven RoHS alternates for restricted materials, and their compatible fab and assembly processes. Various manufacturers are have been using different RoHS materials and strategies, but, till now, no one is proved better than non-RoHS.

Effects of Higher Temperature Soldering. The melting point of lead-free solder pastes is higher than Tin/Lead (Sn/Pb) solder paste. So, to use lead-free solder paste, we have to apply more temperature during component assembly. But it leads to component life reduction, thermal fatigue, plastic IC popcorn effect, delamination of multi-layer PCB, etc.

Solder Joint Reliability. In usage of RoHS solder pastes, reliability of solder joints becomes questionable. Many researchers found the solder joint reliability is lesser than that use Tin/Lead solder paste.

Metal Whiskers. Metal whiskers are very thin hair-like structure developed on metals such as Tin, Zinc, Cadmium, etc. A matured whisker can make short circuits on board. Especially, Tin whiskers are very serious issue to electronics industry today, because of cheaper cost, many component manufacturers are using pure Tin as their preferred lead finish. During the component selection, design engineers and SCM executive are opting for such low cost Tin contained components without knowing about the Tin whiskers.

Cost Issues of RoHS Implementation

Costly Redesigns while migrating to RoHS. Because of RoHS directive, many electronic equipment manufacturers have spent millions of dollars to redesign their products to comply with RoHS.

Costly Redesigns due to Component Obsolescence. Because of RoHS initiative, many component manufacturers stopped the production of conventional non-RoHS components. It causes costly redesigns, if the obsolete component is single source. Military and Aerospace industry is a big example of this category. Military and Aerospace electronic equipment are not covered under RoHS directive, but nowadays they are indirectly forced to redesign their products with obsolescence of non-RoHS components.

Specialized Resources for RoHS Analysis and Implementation. For RoHS analysis and implementation, semiconductor or component manufacturers needed specialized resources to identify, test, and qualify new RoHS alternate materials and manufacturing processes. Of course it created a lot new opportunities to Metallurgical engineers and Quality Analysts (QA).

Increased Component costs and Manufacturing costs. Lead (Pb) is a cheaper material used in component manufacturing. With restrictions on Lead (Pb), semiconductor industry has to investigate for RoHS alternates to Lead (Pb). But except Tin (Sn), many RoHS materials such as Nickel, Palladium, Silver, Gold, etc. are much costlier compared to lead. Tin is not preferable lead finish because Tin creates serious reliability issues such as whiskers. Usage of other RoHS materials increases component costs.