Focused Ion Beam Microscopy
Focused ion beam microscopy combines the methods for the analysis of a sample using a focused ion beam (FIB) and scanning electron microscopy (SEM), as such a sample can be analysed and processed at the same time.
Table of contents
- How does focused ion beam microscopy work?
- Focused ion beam microscopy at Quality Analysis
- Applications: focused ion beam microscopy
- Analytical methods in focused ion beam microscopy
- Advantages of focused ion beam microscopy
- Where is focused ion beam microscopy used?
- In summary: focused ion beam microscopy
How does focused ion beam microscopy work?
During FIB microscopy, an ion beam is focused with the aid of electromagnetic lenses and steered to the sample. For an analysis the beam is guided over the surface and the surface scanned. It is possible to detect either the secondary electrons emitted or the intensity of the beam passing through the sample. If, on the other hand, FIB is used to remove material, the process is the same, however with significantly higher voltage (up to 50 kV).
The analysis in the scanning electron microscope (SEM) functions with the same principle as FIB, however an electron beam is used; this beam is generated by a field-emission cathode. The secondary electrons can also be detected for imaging with this method. However, often the contrast of the electrons scattered back is also used to draw conclusions about the different materials in a sample.
An FIB-SEM microscope combines both types of analysis such that the user can select between them. It is also possible to use the ion beam to machine the material and the electron beam to acquire the image.
Focused ion beam microscopy at Quality Analysis
Even the smallest defects on high-performance components can result in complete failure. At Quality Analysis we rely on the latest focused ion beam microscopy to analyse coatings, coating systems, microstructures, soldered joints and more in nanoscale. It is our goal to identify all flaws reliably and so you can take quick, precise rectification measures.
With the high-resolution ZEISS Crossbeam 350, a field-emission scanning electron microscope (FE-SEM), we combine advanced microscope technologies. The integration of a focused ion beam (FIB) and a femtosecond laser permits not only visual analysis, but also the preparation of high-resolution 3D images and cross-sections with minimal thermal and mechanical effects.
Applications
focused ion beam microscopy
- Analysis of flaws
- Analysis of inclusions and contamination
- Determination of the element composition
- Analysis of deposits at the particle boundaries
- Analysis of intermetallic phases
- Coating thickness measurement
Analytical methods in focused ion beam microscopy
An FIB-SEM microscope combines a focused ion beam system (FIB system) with a scanning electron microscope (SEM). Although it is theoretically possible to undertake imaging using both systems, that is also using the focused ion beam system, in practice the ion beam is primarily used for the preparation of the samples. The primary analysis instrument in focused ion beam microscopy is the scanning electron microscope. Depending on the arrangement of the two systems, the term dual-beam microscope or crossbeam microscope is used.
Advantages of focused ion beam microscopy
Scanning electron microscopy is able to deliver high-resolution images of the smallest samples; it is even possible to prepare three-dimensional images. However, to prevent interactions between the electrons emitted and the atoms in the ambient air, the analysis must be undertaken in a high vacuum. As such, it is not normally possible to access the sample during the analysis. This aspect is a problem particularly if a part of the sample is only found to be of special interest during the analysis in the SEM, or specific material removal is required that can only be undertaken reliably with microscopic visual control.
The focused ion beam system solves this problem by machining the sample with a second beam (using ions instead of electrons) during the analysis. Because an FIB system operates on the same principle as the scanning electron microscope, the combination of the two devices is relatively straightforward. If the ion beam is to be used for machining instead of viewing, the voltage applied must be increased. A further advantage is that this type of preparation does not cause thermal or mechanical changes in the sample.
Where is focused ion beam microscopy used?
Focused ion beam microscopy is used primarily for the detection and analysis of defects in components and assemblies in the electrical engineering industry because it permits the preparation of the sample (e. g. the production of a cross-section) during the analysis. Since no heat is applied to the sample by the FIB during the preparation, unintentional thermal effects on the sample are prevented.
Electrical engineering industry:
Focused ion beam microscopy is utilised in the electrical engineering industry to ensure the integrity and reliability of electronic components. It provides detailed images of microcracks, thermal damage and inclusions in electronic components. These high-resolution images are essential for defect analysis and quality control because they permit the precise assessment of the material characteristics and the quality of the processing. They contribute significantly to the identification of weak spots in soldered joints or the clarification of the causes of failures in ceramic capacitors.
Semiconductor manufacture:
In the semiconductor industry, focused ion beam microscopy plays a crucial role. It permits the detailed depiction of the complex internal structures in semiconductors; this level of detail is imperative for understanding and further developing these technologies. Precise cross-sections make coating structures, flaws and microstructures visible. Particularly valuable is the possibility of measuring the exact thickness of the various coatings and identifying microscopically small defects that could degrade the functionality.
Fuel cells:
Focused ion beam microscopy plays a crucial role in the analysis of fuel cells. By means of precise cross-sectional images, it permits insights into the microstructures of the electrodes and membranes. The high-resolution images offer not only detailed insights into the morphology, they also permit the identification of defects and irregularities that could degrade the efficiency of the fuel cell. Focused ion beam microscopy is therefore an indispensable tool for the further development and optimisation of fuel cell technology.
Lithium-ion batteries:
With precise sectional images, different coatings and materials within the battery cells can be analysed. These images permit not only the identification of structural defects, but also the evaluation of coating thicknesses and the detection of signs of degradation. Focused ion beam microscopy therefore plays a key role during quality assurance and the further development of lithium-ion battery technology.
Coatings and coating systems:
The analysis of coatings, coating systems and lacquers is crucial for various industrial sectors. Focused ion beam microscopy permits detailed characterisation of these surfaces. By means of precise cross-sectional images and the analysis of the coating morphology, it is possible not only to measure coating thickness, but also to identify any irregularities such as cracks, delaminations or inclusions. This understanding is essential for the development of durable, high-performance surface coatings. Focused ion beam microscopy is therefore an indispensable tool for ensuring the quality and functionality of coatings and coating systems in various applications.
In summary: focused ion beam microscopy
Focused ion beam microscopy is the term used for a combination of scanning electron microscopy (SEM) and a focused ion beam (FIB) system. The microscope is primarily used to view the sample, while the ion beam can be used to prepare the sample even during the analysis.
