Nitrogen Generators for SMT Reflow Ovens

As the requirements for miniaturization, reliability, and precision in the electronics industry continue to increase, so does the need for new technologies that can support these demands. One such technology is the use of onsite nitrogen generators for SMT reflow ovens.

Nitrogen generators for SMT reflow ovens offer many benefits over traditional compressed air systems, including improved process control, greater efficiency, and reduced cost of ownership. In addition, nitrogen generators can help improve product quality and yield by providing a consistent and controllable flow of nitrogen gas during the SMT reflow process.

Below we provide an overview of nitrogen generators and explain their benefits and applications in SMT reflow ovens.

What Is Surface Mount Technology (SMT) Nitrogen Reflow Soldering?

Surface mount technology (SMT) reflow soldering is a process in which the electronic components are soldered to the surface of the printed circuit board (PCB). The process of SMT reflow soldering starts with applying a small amount of solder paste on the contact pads of the PCB. Then, the components are placed on the board and are heated to melt the solder paste so that it can flow and make connection with all the components.

There are two main types of SMT reflow solders: lead-free and leaded. Lead-free solder has a higher melting point than leaded solder, so it requires more energy to heat up and melt. This can be a problem when using an SMT reflow oven because it takes longer to heat up.

How Nitrogen Is Used in Soldering Using Reflow Ovens

Nitrogen gas plays an important role in reflow ovens during the soldering process of SMT components.

The main function of nitrogen is to create an inert or non-reactive atmosphere inside the reflow oven. This prevents oxidation and other types of reactions from occurring during the soldering process.

Nitrogen also helps to improve the quality of the solder joints by reducing voiding. Voiding is a common problem in SMT soldering, and it can lead to joint failure. By using nitrogen, voiding can be reduced significantly, which improves the reliability of the solder joints.

In addition, nitrogen can help to improve component production yields by preventing component damage during the soldering process, specifically from overheating.

Stages in Reflow Soldering Using Nitrogen Gas

The following are the main stages in reflow soldering when using nitrogen gas:

Pre-heating: The board and components are heated to a temperature below the melting point of the solder. This helps to remove any moisture from the board and components.
Soak: The board and components are heated to the melting point of the solder. This helps to ensure that all the solder joints are melted and have good wetting.
Cool: The board and components are cooled down to room temperature. This helps to solidify the solder joints and create strong bonds between the components and the board.
Clean: The board and components are cleaned to remove any residue.

Benefits of Using Nitrogen Generators in SMT Reflow Ovens

There are several benefits to using nitrogen generators during the SMT reflow process:

Improved solder joint quality: Nitrogen prevents oxidation, which can lead to weaker solder joints.
Increased productivity: Since nitrogen prevents solder balling, it can help increase productivity by reducing the need for rework.
Reduced costs: Using nitrogen can help reduce costs by reducing the amount of energy required to heat the oven, as well as the amount of time needed to reflow the solder paste. In addition, nitrogen generators are less expensive than cylinder supplies, both in terms of initial investment and ongoing maintenance costs.
Increased safety: There is no risk of explosion with nitrogen generators since they do not store nitrogen under high pressure.
Increased convenience: Nitrogen generators can be used on demand, so there is no need to keep a supply of nitrogen cylinders on hand.
Increased flexibility: Nitrogen generators can be used in a variety of applications, including soldering, welding, and cutting.
Increased efficiency: Nitrogen generators are more efficient than cylinder or bulk liquid nitrogen supply, so they can help save time and money.

Are All Circuit Boards Suitable for Using Nitrogen in SMT?

The type of circuit board that is best suited for using nitrogen in the SMT reflow process is one that has a high solder balling rate. This is because nitrogen can help reduce the amount of solder balling that occurs.

Not all circuit boards are suitable for using nitrogen in SMT, though. Only certain types of circuit boards can withstand the high temperatures required for nitrogen reflow soldering. These include circuit boards using flame retardant materials such as:

FR4 boards
Rogers 4003 boards
Polyimide boards

Nitrogen Generators for Reflow Ovens from Advanced Gas Technologies

Advanced Gas Technologies offers a complete range of standard PSA type nitrogen generators that are suitable for use in reflow ovens. Our nitrogen generators can help improve productivity and reduce costs by reducing the amount of time needed to reflow solder paste.

If you’re interested in learning more about our nitrogen generators for electronics manufacturing, or if you have any questions, please contact us today. We’ll be happy to answer any questions you have and help you find the best nitrogen generator for your requirements.