Physical and Chemical Mechanisms of Preparation Techniques - Sample Preparation Topic for Transmission Electron Microscopy - page 97

Fig. 5.11 Diagram of a type
of FIB column

Liquid-
Metal
Source

Suppressor

Extractor

Lens 1

Diaphragm

Octupole 1

Deflector

Lens 2

Specimen
Holder
Deck

Octupole 2

positive ions, which are extracted and accelerated by a voltage of a few kiloelectron
volts (Fig. 5.12) . The current density is adjusted by selecting the current of the
electrostatic lenses and the size of the aperture. These last two parameters determine
the diameter of the ion beam, which can be less than 10 nm. Material abrasion occurs
when the ion beam is scanned over the area of interest (Fig. 5.13) .

Fig. 5.12 Diagram of the
gallium source

Electrical Contact

Insulator

Heating Coil

Tungsten Needle

Gallium Reservoir

Extraction Electrode