| The experimental conditions for FIB specimen preparation vary from lab to lab mostly depending on the habit and application of the FIB users. Examples of experimental FIB conditions are shown in Table 4500. The most critical parameters are the parameters at the final cleaning steps. Especially, to obtain clean samples, low kV such as 8 kV, 5 kV, and/or 2 kV should be carried out at the final steps [1]. On the other hand, specifications of some FIB systems are listed at page2476.
Table 4500. Experimental conditions used for the preparation of the TEM specimens.
| Step |
I (nA) |
Milling box type and relevant data |
Tilting |
Time (min) |
| Pt deposition |
0.3 |
Rectangle: x = (10–20 μm), y = 2.5 μm, z = 2 μm |
52° (sample surface ⊥ to the ion beam) |
~8 to 12 |
| Bulk milling |
20 |
Regular cross-section |
52° |
20 to 40 |
| Bottom cutting |
20 |
Rectangle |
−10° |
~4 to 5 |
| Rough cleaning |
3 |
Rectangle and cleaning cross-section (in sequence) |
54° and 50° (grazing angles of ±2°) |
~10 to 30 |
| Lift out (internal) |
0.1 (Pt deposition), 1.0 (releasing lamella from bulk) |
Rectangle |
0° |
~15 |
| Welding lamella to grid and releasing from the extraction needle |
0.3 |
Rectangle |
0° |
~15 |
| Thinning (final thickness ~100 nm) |
0.3 and 0.1 |
Rectangle and cleaning cross-section (in sequence) |
54° and 50° (grazing angles of ±2°) |
20 to 30 |
| Cleaning |
0.029 and 0.070 (Eion beam = 5 kV) |
Rectangle (nominal z = 10–40 nm) |
60° and 44° (grazing angles of ±8°) |
30 to 60 (in steps of <60 s each one) |
[1] High-Quality Sample Preparation by Low kV FIB Thinning for Analytical TEM Measurements, Sara Bals, Wim Tirry, Remco Geurts, Zhiqing Yang, and Dominique Schryvers, Microsc. Microanal. 13, 80–86, (2007).
[2] Evaluation of Top, Angle, and Side Cleaned FIB Samples for TEM Analysis, Eduardo Montoya, Sara Bals, Marta D. Rossell, Dominique Schryvers, and Gustaaf Van Tendeloo, Microscopy Research and Technique 70:1060–1071 (2007).
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