Dispensing processes

mta – the best solution for all kind of dispensing processes

The choice of the appropriate dispensing process depends primarily on the workpiece and the specific material. In addition, the dispensing process must be considered in correlation with the production environment.

The requirement is to maximize the functionality of the workpiece and its service life and to make the necessary process efficient and economical. Regardless of the adhesive bonding or potting application, Unitechnologies has the optimal mta-dispensing technology.

Adhesive bonding

Adhesive bonding is used to join two or more parts together. The adhesive dots or lines must be precisely applied onto defined areas. For this purpose, Unitechnologies offers various dedicated robots.

Especially in recent years, bonding has become increasingly established as an essential part of dispensing technology. There are numerous advantages such as weight savings or simplified part handling, compared to conventional joining techniques such as welding or screwing.


Sealing (FIPG and CIPG)

The application of liquid seals in the shape of a material bead is commonly referred to as “sealing”. These processes protect sensitive components from dust, temperature-related influences, moisture and other factors. In addition, this method is used to bond different components of the workpiece. The main scopes of this dispensing technology are the sealing of housings and housing covers.

Depending on whether the liquid seal is already crosslinked at the time of the joining process, a distinction is made between FIPG (“formed in-place gasket”) and CIPG (“cured in-place gasket”) processes.

The application of the seal is usually automated along a specific, predetermined dispensing contour. A precise and repeatable liquid seal application is important. For this purpose, Unitechnologies offers various dedicated robots. The control of these robots allows the interpolation of dispensing quantities with the movement speed of the axis system in order to achieve constant dispensing quantities.


Potting

One scope of dispensing technology is the encapsulation of electrical components with the aim of increasing the service life of the processed workpieces. The intended housing or mold of a workpiece is filled or potted with a low-viscosity casting material (PU, epoxy, silicone). The process is used wherever sensitive electronic components need to be protected from chemical, corrosive or mechanical influences.

In this way, cable entry, sensors or printed circuit boards for example can be optimally protected.

The potting process requires a precise quantity of potting compound and individual component quantities with high repeatability. The mta dispensing systems are characterized by great precision.


Conformal coating

The “sealing” process describes the application of a thin layer of cast resin or protective varnish. Depending on the application, a partial or complete sealing is carried out on the printed circuit boards. For a reliable protective effect, a thoroughly coated surface including sharp edges, solder joints and other surface structures, must be ensured.

The coating protects against environmental influences such as moisture, chemicals, dust and corrosion. As a result, the workpieces have an increased service life and operational reliability.

In the field of large-scale production, a robot-assisted material application is established.


Dam & fill

Dam & fill applications focus on protecting sensitive structures on printed circuit boards. In this process, a first barrier (dam) is applied with a high- viscosity material. Subsequently, the defined area is filled with a flowable filling material (fill).


Glob top

In glop top encapsulation, sensitive components (e.g. semiconductor chips with wire bonding) are protected against mechanical loads, such as vibrations or temperature fluctuations, by applying a low-viscosity casting resin.


Solder paste dispensing

The processing of solder pastes requires a precise and repeatable application. Especially for highly integrated components (increasingly smaller products with increasing density of components), it is necessary to dispense the solder paste in very small quantities into difficult-to-reach areas. Dispensing heads with needles for very small quantities and contactless jet dispenser, based on pneumatically or piezoelectric valves, are used.


Microdispensing

Microdispensing describes the application of low-viscosity material in the volume range of a few microliters. In this process, high volume accuracy and repeatability are particularly important. Unitechnologies offers very precise mta dispensing technology accordingly.


Underfill

Underfill applications are used when chips need to be mechanically stabilized. The gap between the substrate and the chip is filled with a low-viscosity material. The capillary effect pulls the underfill into the space between them until it is completely filled with the casting resin.


Heat dissipating

Thermal management in the electronic component is necessary in order to reliably dissipate the heat generated in the component and thus prevent performance losses or defects due to overheating.

A liquid thermal conductive adhesive is often applied for this purpose, which adapts flexibly to the respective substrate surface. Due to the high-viscosity and very abrasive materials, the focus is on a low-wear dispensing system.