Multi Vacuum

The Multi Vacuum soldering process is essential for the quality for modern applications. In the Multi Vacuum soldering process, an assembly can be subjected to several vacuum applications during one soldering process. The Multi Vacuum process offers the possibility of carrying out vacuum processes both before and during the melting of the solder paste.

Benefits of Multi Vacuum for your assembly

Higher mechanical stability

Increased lifetime of the assembly

Improved heat removal (power electronics)

Reduced signal interference (high frequency technology)

Cost savings. Since the performance of the individual component is higher due to the void reduction, fewer components are required for the overall performance of the assembly.

  • Useful supplement to the vapor phase soldering process for high quality requirements.
  • Due to the arrangement of the vacuum chamber outside the hot process zone (Clean Vacuum), reduced maintenance work as well as longer maintenance cycles are guaranteed

How Multi Vacuum works

Step 1

  • Start of the vacuum process after melting of the solder paste.
  • The void (inclusion in solder joint) is present in its original size.

Step 2

  • The vacuum is constantly increased.
  • The void increases in size due to the resulting pressure difference.

Step 3

  • The void continues to grow until it reaches the edge of the solder deposit.
  • There it opens and releases the trapped air to the outside.
  • The escaped air is sucked out by the applied vacuum.

Step 4

  • The vacuum is further increased.
  • The air from the opened void is further extracted.
  • The shrinkage of the void begins.
  • This continues until the maximum vacuum pressure is reached.

Step 5

  • After the maximum vacuum pressure has been reached, the vacuum is reduced again at a constant rate.
  • The remaining void closes again.

Step 6

  • The vacuum pressure is further reduced at a constant rate.
  • As a result, the ambient pressure on the remaining air entrapment increases constantly again.
  • The remaining void becomes smaller and smaller.

Step 7

  • The vacuum process ends.
  • The ambient pressure is normal again.
  • The remaining air entrapment is reduced to a minimum.

The Special - Multi Vacuum by ASSCON

  • In the Multi Vacuum process, the steps can now be repeated again.
  • This allows the remaining air inclusion to be reduced even further.
  • This is useful, for example, in the case of extremely large connection surfaces (e.g. in power electronics).

Before - After

Air inclusions (voids) in a component (MOS FET) before and after treatment with Multi Vacuum

Our vacuum systems