Material Analysis and Damage Analysis: TOF-SIMS for the Identification of Emission Products
Contamination from adjacent components
Today’s manufacturing technology makes it possible to produce modern components from a wide variety of materials and components. On the one hand, this enables high-performance functional properties. On the other hand, it allows for the realization of a wide range of designs. Products for the automotive and electronics industries are particularly common examples of such components made up of multiple parts. Vehicles contain numerous different materials (plastics, metals, glass, etc.) that are either in direct contact with one another or in close proximity. Electronic devices such as computers, control units, or smartphones are equally complex. Here, a wide variety of components—such as high-density printed circuit boards, soldered connections, and the housing—are installed in the tightest of spaces due to their compact designs.
In addition to their high technical complexity, these systems also exhibit a high degree of chemical complexity. While the individual components function reliably, their combination can give rise to unexpected challenges that may ultimately lead to failures or damage. Damage caused by contamination is not an isolated case: In the coating industry, even the smallest amounts—submonolayers of substances—are sufficient to cause problems such as craters, pitting, and delamination, either immediately or after a delay. In electronic components, accumulations of volatile substances from the environment on contacts, connectors, and relays lead to failures. These contaminants can often result from migration processes from the interior or from contact with the environment.
A frequently underestimated phenomenon is the outgassing of volatile substances from materials and components and the adsorption of these substances onto adjacent parts. This can lead to unwanted damage and malfunctions.
Common problems and damage:
Beispiel für Probenformen
- Detachment of bond pads and bond wires
- Deposits and corrosion on electrical contacts (connectors, pins, buttons)
- Product discoloration
- Paint peeling
- Change in resistance values due to deposits on electrical components (capacitors, relays, resistors)
To ensure the reliability of modern products, the analysis of such chemical interactions is of great importance. Analysis using TOF-SIMS enables reliable material and damage analysis of emission products.
TOF-SIMS: Analytik von Emissionsprodukten
TOF-SIMS (Time-of-Flight Secondary Ion Mass Spectrometry) is a highly sensitive method for the trace analysis of emissions. With conventional methods, characterizing adsorption layers can be problematic due to the small sample sizes involved. The TOF-SIMS method, on the other hand, enables the detection of even the smallest traces of inorganic and organic compounds—regardless of their chemical class.
This allows for the direct, retrospective analysis of the adsorption layer formed during the emission process without the need for complex sample preparation. Additionally, it is possible to proactively recreate the emission and classify the emitting substances.
component
- PU foam
- fluoropolymer
- Solder wires
- PA housings, heat-shrink tubing
- Recycled PVB
- PBT connector
- PA granules
- Paper with PDMS
- Diaphragm (pump)
- Rubber gasket
- Silicone gasket
- PVC hoses
typical outgassing product
- Diazabicyclooctane (DABCO)
- Trifluoroacetic acid (TFA)
- Iodine, benzotriazole, resin acids
- Red phosphorus
- medium-chain fatty acids/fatty acid esters
- Bromine, Antioxidants
- Iodine, melamine
- Silicone (PDMS)
- Iodine, quaternary ammonium compounds, PDMS
- benzothiazyl sulfide
- PDMS
- Diethylhexyl phthalate (DEHP)
Material analysis of adsorption layers
Material analysis of the emission products from components and the affected failed parts using TOF-SIMS allows conclusions to be drawn about the source of the contamination. In this process, the emission products can be generated under real-world environmental conditions (temperature and pressure) in a controlled laboratory setting and then chemically characterized using special adsorption stages. In addition, chemical comparison allows the sources of the emissions to be clearly identified.
Case Study 1: Investigation of Stress Cracks in Polycarbonate Components
The reason for the material analysis is the cracking of polycarbonate (PC) clips installed in close proximity to a polyurethane sealing foam.
Analysis of the emission product following outgassing of the PU foam reveals that the volatile substance DABCO (diazabicyclooctane) is emitted from the foam. By comparing this with the surface analysis of the failed component itself, DABCO can be identified as the cause. DABCO belongs to the class of amines and can lead to degradation and decomposition in certain polymers.
Case Study 2: Material Analysis of Solder Component Emissions
In this example, solder material is being analyzed. In material analysis, the detection of halides is particularly important, as they have properties that promote corrosion.
In addition to benzotriazole, which is commonly used as a rust inhibitor, the halogen iodine can be detected.
Case Study 3: Investigation of a sealing ring made of fluorinated polymers
Sealing gaskets are used in many components; due to their excellent material properties, they often contain fluorinated polymers.
For the purposes of the investigation, the emission was simulated. Trifluoroacetic acid (TFA) can be detected in the adsorption layer. Trifluoroacetic acid belongs to the class of per- and polyfluoroalkyl substances (PFAS); it is acutely toxic and corrosive to metals.
Case Study 4: Analysis of Plastic Enclosures for Additives
In this case, the cause of the failure of the electronic contacts is being investigated. A direct analysis reveals a deposit of red phosphorus. The surrounding polyamide plastic housing is suspected to be the source, as red phosphorus is used there as a flame retardant.
The emission of red phosphorus is replicated under environmental conditions in the laboratory. Material analysis shows that it is present as an additive in the plastic housing and is leaching out of the polymer.
Summary of results: TOF-SIMS for precise damage analysis and quality control
The results demonstrate that emissions from adjacent components are a frequently underestimated source of contamination and resulting functional failures. This is particularly relevant in the automotive and electronics industries, where complex components made from a wide variety of materials and parts are produced.
The TOF-SIMS method enables the precise investigation of contamination pathways and the identification of a wide variety of chemical substances. Advantages of material and damage analysis using TOF-SIMS:
- High sensitivity: precise characterization even of minimal contamination
- Reproducibility: Emission processes can be replicated under real-world environmental conditions
Contact us to learn more about our material and damage analyses. We are happy to assist you with any questions you may have regarding industrial or medical applications.
