4. After changing to a new FIB current, you may need to run the
auto contrast routine for the FIB view. Additionally, take several brief FIB images to allow any image/beam drift to settle
and to focus at the lamella position (see Note 13).
5. Start rastering the patterns. Monitor the milling progress regularly with the FIB and SEM. If desired, you may save SEM
snapshots of intermediate milling steps to judge progress.
6. When milling at this current is finished, switch to a lower
current, reduce the milling pattern separation, and adjust the
pattern dimensions (see Table 4 and Fig. 6)
7. Continue milling while reducing pattern separation and FIB
current until you reach a pattern separation of $200 nm (see
Note 14 and Table 4)
8. On some specimens, it may be necessary to perform a final
milling step with a stage tilt of Æ0.5
from the desired angle
to compensate for the slightly diverging FIB beam (Fig. 6
“Final Mill”). In this case, only enable milling on the side
corresponding to the tilt direction (i.e., only enable the top
pattern if milling with a +0.5
tilt. See Note 15) [13].
9. Continue on to other lamella locations as desired.
Sample Retrieval
About 1 h before retrieval, begin purging the loading station with
dry nitrogen gas. If the loading station is at liquid nitrogen temperatures, increase the purge time to 2 h. The sequence of events
for sample retrieval is essentially the reverse of sample loading, but it
is reproduced here for the sake of completeness.
1. After completing all lamellae, perform a final cleaning step to
remove amorphous ice buildup (see Note 16). When finished,
close the SEM and FIB column valves.
2. Make sure the shuttle holder in the loading station is in the
vertical position.
3. Stop purging the loading station and fill with liquid nitrogen.
Allow to cool until the liquid is no longer boiling. Refill as
needed. Place the transfer lid on the loading station.
4. Open the transfer arm valve, then press the “P” button to
pump the airlock and move the stage to the loading position.
5. Wait for the airlock gate valve to unlock. Open the airlock gate
valve.
6. Insert the transfer arm fully and close the grabber. Test the hold
by pulling back slightly.
7. Fully retract the transfer arm and lock the arm in place. Close
the transfer arm valve and the airlock gate valve.
8. Press “V” to vent the quickloader airlock. Retrieve the transfer
arm and place it onto the transfer lid.
70
Vinson Lam and Elizabeth Villa
auto contrast routine for the FIB view. Additionally, take several brief FIB images to allow any image/beam drift to settle
and to focus at the lamella position (see Note 13).
5. Start rastering the patterns. Monitor the milling progress regularly with the FIB and SEM. If desired, you may save SEM
snapshots of intermediate milling steps to judge progress.
6. When milling at this current is finished, switch to a lower
current, reduce the milling pattern separation, and adjust the
pattern dimensions (see Table 4 and Fig. 6)
7. Continue milling while reducing pattern separation and FIB
current until you reach a pattern separation of $200 nm (see
Note 14 and Table 4)
8. On some specimens, it may be necessary to perform a final
milling step with a stage tilt of Æ0.5
from the desired angle
to compensate for the slightly diverging FIB beam (Fig. 6
“Final Mill”). In this case, only enable milling on the side
corresponding to the tilt direction (i.e., only enable the top
pattern if milling with a +0.5
tilt. See Note 15) [13].
9. Continue on to other lamella locations as desired.
Sample Retrieval
About 1 h before retrieval, begin purging the loading station with
dry nitrogen gas. If the loading station is at liquid nitrogen temperatures, increase the purge time to 2 h. The sequence of events
for sample retrieval is essentially the reverse of sample loading, but it
is reproduced here for the sake of completeness.
1. After completing all lamellae, perform a final cleaning step to
remove amorphous ice buildup (see Note 16). When finished,
close the SEM and FIB column valves.
2. Make sure the shuttle holder in the loading station is in the
vertical position.
3. Stop purging the loading station and fill with liquid nitrogen.
Allow to cool until the liquid is no longer boiling. Refill as
needed. Place the transfer lid on the loading station.
4. Open the transfer arm valve, then press the “P” button to
pump the airlock and move the stage to the loading position.
5. Wait for the airlock gate valve to unlock. Open the airlock gate
valve.
6. Insert the transfer arm fully and close the grabber. Test the hold
by pulling back slightly.
7. Fully retract the transfer arm and lock the arm in place. Close
the transfer arm valve and the airlock gate valve.
8. Press “V” to vent the quickloader airlock. Retrieve the transfer
arm and place it onto the transfer lid.
70
Vinson Lam and Elizabeth Villa