In case of the Leica EM RES102, an oscillating movement can be used in addition to the sample rotation. In doing this, both the zero point and the angle of the oscillation can be adjusted. The zero point should be set up so that the incidence of the ion beam is vertical with respect to the adhesive joint. If the sample is oscillating and the milling angle is flat, the layers with lower milling rate protect the layers with higher milling rate. That results in a uniform milling of the entire sample.
Preparation Conditions
Mechanical pre-preparation: Double sided polishing with diamond foils: 15 µm, 9 µm, 6 µm, 3 µm, 1 µm and 0.5 µm until the final sample thickness of 60 µm.
Ion milling
| Sample holder: | Quick-clamp-holder |
| Acceleration voltage: | 7 kV |
| Milling angle: | 4° |
| Sample movement: | Oscillation (±45°) |
Final step
| Sample holder: | Quick-clamp-holder |
| Acceleration voltage: | 2 kV |
| Milling angle: | ±4° (alternating with one ion gun) |
| Sample movement: | Oscillation (±45°) |
Results
The multilayer system, the preparation of which needs to be carefully, could be evenly thinned despite the wide difference in the sputter rates. All components are uniform electron transparent over a length of several 100 µm. An examination of the layers and their interfaces in high resolution is possible.
