Chapter/Index: Introduction | A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | Appendix
| The procedure of conventional, cross-sectional FIB TEM preparation method is: i) Locate an area of interest (AOI) and cut to <3 mm in length to fit the standard TEM sample holder later. ii) Mechanically polish the sample to less than 50 µm in thickness in order to reduce FIB milling time. Different mechanical polishing methods can be used to cut the sample to small size: iii) Delineate the location of the AOI with deposition, line cut, and/or drilling holes. iv) Deposit a metal line on the AOI to prevent damage on the top portion of the specimen from sputtering. Typical dimensions of the metal line are 1~2 µm wide × 5~30 µm long × 2~3 µm high. v) Mount the sample on a slotted, half TEM Cu grid as shown in Figure 2543.
Figure 2543. Examples of slotted, half TEM Cu grids. vi) Sputter large trenches on either side of the AOI using a high Ga+ beam current. vii) Reduce the beam current to perform milling on each side of the specimen to reduce redeposition of sputtered material onto the surface of the specimen. viii) Clean the specimen by further reducing the beam current until the membrane is thinned to < 100 nm. The final thickness of the specimen will depend on the information you need and the density of the material(s). A final electron transparent portion of the specimen is usually 1~5 µm wide × 5~20 µm long. The preparation time for each specimen varies, for instance, a TEM specimen of a Si-based ICs (integrated circuits) may be prepared in less than 1 hour, while a large specimen from fuel cells can take more than 4 hours.
[1] Anderson, R., Klepeis, S.J., 1997. Combined tripod polishing and FIB
method for preparing semiconductor plan view specimens. In: Anderson, R.M., Walck, S.D. (Eds.). Materials Research Society Symposium Proceedings, 480. Materials Research Society, Pittsburgh,
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