Electronics: Why technological development requires adhesive qualification

Smaller components, higher power densities, new material combinations and increasing reliability requirements: electronic assemblies are becoming more complex. This also applies to joining technology. Adhesives have long since ceased to merely serve the purpose of joining two components together. They can transfer heat, provide electrical insulation or conduct electricity, protect against environmental influences and compensate for mechanical stresses.

However, as the technical possibilities increase, so too do the demands placed on those who develop, plan, carry out and monitor bonding processes. This is because a reliable bond is not achieved simply by selecting a suitable adhesive. It is crucial to understand and master the interrelationships of the entire process.

More complex applications require a deeper understanding of the process

This trend is particularly evident in the electronics sector. In flip-chip underfill, for example, the adhesive must absorb stresses between the chip and the substrate. In die-attach for power electronics, factors such as heat dissipation, electrical properties and mechanical requirements must be taken into account.

This also changes the demands placed on the specialists involved. It is not enough simply to apply an adhesive according to specified parameters. Anyone wishing to master an adhesive bonding process with confidence must understand how the material, surface, design, adhesive and manufacturing conditions interact. This knowledge becomes all the more important as bonding areas and adhesive quantities become smaller and process windows narrower. Deviations in surface preparation, dosing or curing can directly affect the quality of the bond.

Adhesive bonding technology affects various functions within a company

Knowledge of adhesive bonding technology is therefore not only required in the immediate production process. Key decisions regarding the subsequent adhesive bonding process are already made during the development phase. The design department, for example, defines bonding surfaces and joint gaps. In work planning, requirements are translated into an industrial process. Quality assurance must be able to assess which process parameters are relevant and how these are monitored. The tasks differ – yet technical responsibility for a controlled process is spread across several functions. This is precisely why qualification in bonding technology must also be considered on a case-by-case basis. Not every employee requires the same level of knowledge of adhesive bonding technology. It is crucial that qualifications and responsibilities are aligned.

Workforce training creates a common technical foundation

Established qualification pathways are available for adhesive technology. With the European Adhesive Bonder (EAB), the European Adhesive Specialist (EAS) and the European Adhesive Engineer (EAE), there are different qualification levels for various tasks and areas of responsibility. The aim is not to provide comprehensive training to as many employees as possible. It is about building the necessary expertise at the relevant points in the process.

In my view, a key point is understanding the interrelationships. Anyone who understands why a surface needs to be prepared, why a specific process window must be adhered to, or why a change to the design can affect the bonding process, is better able to assess deviations and determine appropriate measures. In this way, training and further education create a common technical foundation between development, planning, production and quality assurance, ensuring that all those involved ‘speak the same language’ and can communicate efficiently.

Standards make competence an integral part of quality assurance

This importance of qualification is also reflected in the regulations governing adhesive bonding technology. Standards such as ISO 21368 regard bonding as a specialised process whose quality cannot be assured by the finished product alone. Therefore, companies must not only have a thorough understanding of materials and manufacturing parameters; responsibilities, process monitoring and the qualification of the personnel involved also play a key role. Qualification is therefore not a training topic detached from the actual manufacturing process. It is an integral part of systematic quality management for adhesive bonding processes.

New requirements do not render existing knowledge obsolete

In the electronics sector in particular, materials, designs and manufacturing processes are constantly evolving. At the same time, new requirements are emerging – for example, due to higher power densities, increasing miniaturisation or demands regarding repairability and recyclability. However, this does not mean that fundamental knowledge of adhesive bonding technology needs to be constantly replaced. On the contrary: the faster applications change, the more important a solid understanding of the fundamental principles becomes. Anyone who is familiar with just a single process step can only respond to changes to a limited extent. By contrast, those who understand the interactions between materials, surfaces, design and process can also apply this knowledge to new applications.

For me, this is precisely where a key role of continuing professional development lies: not merely explaining existing processes, but empowering people to understand the interrelationships in adhesive technology and apply them to new challenges.

Technological development and skills development go hand in hand

Adhesive bonding technology offers many possibilities for electronic assemblies. However, whether these possibilities can be utilised industrially does not depend solely on new adhesives, equipment or manufacturing processes. It is also crucial whether companies possess the necessary knowledge to develop safe and reproducible processes from these possibilities and to master them in the long term.

That is why technological development and skills development should not be viewed in isolation from one another. As applications, materials and processes change, the knowledge of the people involved must also evolve.

Continuing professional development is therefore not a secondary measure. It is a prerequisite for ensuring that the technical possibilities of adhesive bonding are transformed into reliable industrial applications.