What is SMT:
SMT is a kind of Surface Mounted Technology (shorted for Surface Mounted Technology), and is one of the most popular technology and process in the electronic assembly industry

What is the characteristic of SMT:
High assembly density, small volume and light weight of electronic products. The volume and weight of the SMD components is only 1/10 of the traditional plug-in component. Generally after adopting SMT, the electronic products volume will reduce 40% ~ 60%, and the weight will reduce 60% ~ 80%.
High reliability, strong shake-proof ability and low soldered dot defect rate.
Good high frequency characteristics can reduce the interference from electromagnetic and radio frequency.
Automation can be easy to realize so that it can improve production efficiency and reduce the cost of 30% ~ 50%, saving material, energy, equipment, manpower and time, etc.

Why do we use SMT:
The trend of electronic products is miniaturization, and previous plug-in components are unable to shrink.
The function of electronic product is more complete, and integrated circuit (IC) has adopted SMD components instead of plug-in components, especially in large-scale, high-integrated IC.
Mass production and production automation. The manufacturer will meet customer needs and strengthen the market competitiveness with low cost and high yield, producing high quality products.
The development of electronic components, the exploitation of integrated circuit (IC), multiple applications of semiconductor materials
Electronic technology revolution is imperative to chase the international trend.

Why do we use lead-free process:
Lead is a toxic heavy metal. Human body absorbing excessive lead will cause poisonous, absorbing bits of lead may have negative effects to the persons intelligence, nervous system and reproductive system. The global electronic assembly industry consumes about 60,000 tons of solder every year and increases year by year, resulting in severe environmental pollution of lead salt industrial dross. Therefore, to reduce the use of lead has become the focus all over the world. Many big companies in Europe and Japan are vigorously exploiting lead-free alternative alloy, and plan to gradually reduce the use of lead in the electronics assembly from 2002 and eliminate thoroughly till 2004. (the traditional solder composition 63 sn / 37 pb . In the present electronic industry, lead is widely used).