What is dispense application?

Solder paste or heat curing SMT adhesive is filled in a syringe to be applied on the soldering pad by a dispenser.

Traditionally, solder paste has been applied to a PCB by printing it using a stencil and a squeegee. However, change in soldering process and product structure made it impossible for the printing application to feed the solder paste at desired soldering pad. As a result, demand for dispense application is increasing.

In addition, dispensing application does not require a metal stencil, which is necessary for the print application. Consequently, time and cost to renew a stencil upon prototype making can be reduced.

Market demand

Along with the increase in demand for dispense application, desirable size (diameter) of the dispensed solder paste becomes diverse and that the particle size of solder powder should also be optimized.

Solder powder particle sizes and their compatible dispense diameters are shown below.

• Solder powder particle size: Possible dispense diameter *

Type 4 (20~38μm): >0.7mmφ (Straight nozzle)

Type 5 (10~25μm): >0.4mmφ (Tapered nozzle)

Type 6 ( 5 ~25μm): >0.25mmφ (Tapered nozzle)

* Reference only: Dispensability may change depending on the solder paste and dispense condition

Example of dispense application

Increase the freedom of product design

Solder paste can be provided to the area where conventional print application could not and restriction regarding product design  can be reduced.

Applicable to assembled PCB

Dispenser allows vertical solder paste application, that the solder paste can be fed to the pads on a PCB which has electronic components already mounted. 

Heat-curing adhesive on reflowed PCB to prepare for wave soldering or reworking after reflow soldering has made easy.

No need for metal stencil

Several metal stencil may be needed during a prototype making upon model change, but not with dispensing application.