Adhesion is typically associated with the fact that two or more surfaces are joined. An adhesion failure may occur if the surfaces are contaminated, or if unsuitable materials or processes (e.g. adhesives, pre-treatments) are used. Many different failure modes and causes of failures exist for different materials systems. For example:
- For polymer materials (for example packaging), surface pretreatments or coatings, failures often occur due to contaminations in or on the materials.
- The cause for defects of solder joints may be material impurities, oxide layers or diffusion processes.
The analysis of such failures often requires the use of surface analytical techniques. In most cases, both sides of the delaminated interface are examined. Additionally the analysis of adjacent volumes is appropriate because the composition of the materials used is often not (well) known. Thus, the substances found in the defective area can be optionally assigned to the raw materials, or clearly identified as contamination.