Metal films
The metal films can be prepared automatically with the Leica EM RES102. In addition, single milling steps or complete programs can be written. These will then be checked by the computer and, with the help of an optical automatic termination, will be stopped at the optimum point of time. The presence of the user during the milling process is not necessary. Time-consuming sample preparations can thereby be carried out overnight.
Preparation Conditions
Mechanical pre-preparation: Disc puncher to cut out 3 mm discs.
Ion milling
| Sample holder: | Quick-clamp-holder |
| Acceleration voltage: | 7 kV / 2 kV (final thinning) |
| Milling angle: | 16° and 6° |
| Sample movement: | Rotation |
Results
The metal films can be prepared to the electron-transparent over a wide range. The influence of the milling angle is clearly discernible with Al films. While the sample processed with a milling angle of 6° is free from visible defects (see Fig.1), the sample prepared with 16° shows a high defect density (Fig.2).
Metal sheets
Metal sheets are thicker than 100 µm. Mechanical pre-preparation is necessary to obtain an acceptable initial thickness and a good surface quality for ion milling. An ultrasonic cutter can be used to get a 3 mm disc. It is also possible to use the core drill of the Leica EM TXP.
Preparation Conditions
Mechanical pre-preparation:TXP core drill to get a 3 mm disc. TXP for double sided polishing down to a final thickness of 50 µm. Diamond foils: 6 µm, 3 µm, 1 µm and 0.5 µm at 2000 rpm.
Ion milling
1. Step:
| Acceleration voltage: | 7 kV |
| Current: | 2.6 mA |
| Milling angle: | ±6° |
| Sample movement: | Rotation |
| Milling time: | 4h |
2. Step:
| Acceleration voltage: | 2 kV |
| Current: | 1.5 mA |
| Milling angle: | ±6° |
| Sample movement: | Rotation |
Results
Clean and large electron transparent area.
Some grains show lattice damages which may be due to the rolling process during manufacture.
