The Restriction of Hazardous Substances (RoHS) directive was issued in 2006 for the PCB industry, which regulates the import into the European Union of electronic equipment whose electronic parts contain materials restricted by the directive.

The following hazardous materials are subject to restrictions:

Restriction of RoHS materials

— Mercury;
— Lead;
— Cadmium;
— Hexavalent chromium;
— Polybrominated biphenyls;
— Polybrominated diphenyl ether.

The materials may now only be present in the production at a rate of 0.1%. It is not the entire device that is tested for compliance, but the part where the substance may have been used. For example, a certain conductive material containing a banned substance may be used when metallising the holes of a printed circuit board. Only the metallised part of the device will be tested for compliance, not the whole board.

Apart from the obvious impact of hazardous substances on the production workers themselves, which is unacceptable, the use of hazardous substances is dangerous to the general level of the environment.

Why it is important

More than forty million tons of e-waste are produced worldwide every year. Only one tenth is recycled. The rest ends up in Third World countries, in the form of huge landfills. This waste has a direct impact not only on nature, but also on human health: electronics emit lead, which can contaminate people when it falls into the water supply after the rains.

Therefore, the less hazardous substances in non-recyclable waste, the less harmful it is to mankind. As a global manufacturer, Sai Fon Technologies is committed to following all guideline recommendations, and does everything in its power to ensure the safety of mankind.

Lead-free top coat

Pre-tinning is a final essential step in the production of printed circuit boards

and is required to prevent oxidation of the copper used to coat the tracks, contact pads, vias and so on.

SaiFon Technologies, in compliance with the RoHS directive, does not use lead tinning. Instead, the Lead Free HASL method has been chosen.

This method has a number of benefits, which accounts for its popularity:
— Ease of production;
— Well-established processes;
— Low cost of the basic materials;
— Safety for employees;
— Good solderability;
• Large temperature range for thermal processing;
— Maintaining the long-term performance of components even under the harsh operating conditions of electronic products.

A high temperature regime is required for tinning - this is between 260 and 270 degrees Celsius. This temperature can deform the printed circuit board.

The technology cannot be used for SMD/BGA components which have a component pitch of less than 20 millimetres. Applying a coating to such components can lead to short-circuits.

The vapours emitted during coating may not comply with international production standards, which may also raise questions.

As well as leed free tinning, Saifon Technologies can apply other types of coating to your PCB, which can be found on the company's website. The company uses its own equipment and only tried and tested application methods that are accepted by international standards and requirements.

The leed free method has a number of nuances that are important to know before using this tinning method.

PCB design complex