What is jet dispensing?

Jet dispensing is a non-contact solder feeding method. Deposited solder paste shape will be stable without metal stencil and solder paste can be fed to a PCB with complex design. Multiple deposits can be shot at the same soldering pad without inducing defect by any contact during depositing.

Surface mount device is becoming more minute and versatile, that it now requires to feed solder in more complexed PCB, such as 3D designs.

Air dispensing is commonly used to provide solder paste  when print application is not available (e.g. rework after reflow, add solder paste, or deposit solder paste in cavity).

However, air dispensing still requires the nozzle to contact the target pads and needs certain clearance in the process. Consequently, non-contact jet dispensing method has been demanded.

Issue with jet dispensing and countermeasure

– Non-contact dispense at high-speed causes solder paste to lose the dispensed shape  and to splatter.

– Using conventional syringe on jet dispenser causes poor solder paste rounding and causes drooling.

– Needle can clog easily.

Solution

– Improve the shape retention and stabilize the dispensed shape

– Reduce viscosity while improving shot separation to mitigate drooling

– Viscosity adjustment solder powder size optimization (2~10μm) to prevent needle clogging

Compatible with various dispense diameter

– Available in 3 solder powder grain sizes. Select the grain size most suited for the nozzle diameter (100~400μm)