ZEISS
3 Product and Functional Description | 3.2 Main Components
3.2.3 Ion-sculptor Focused Ion Beam (FIB) Column (Optional)
Purpose
The Ion-sculptor Focused Ion Beam (FIB) column is the part of the microscope, where ions are
emitted, accelerated, focused, and deflected.
1
2
3
4
5
Fig. 10: Schematics of the ion optics
1
Ion source
Liquid metal ion source of gallium (Ga⁺).
2
Variable apertures
3
Ion beam
4
Objective lens
5
Specimen
Operating
Principle
Gallium ions (Ga⁺) are extracted from a liquid metal ion source
1
. The ions are accelerated by
the acceleration voltage to an energy of maximum 30 keV. The ion emission is adjusted by the ex-
tractor and the suppressor voltage.
Gallium is used up during operation. Therefore, the gallium emitter cartridge is a consumable.
The gallium emitter has to be regenerated by heating from time to time; the heating procedure
removes the gallium oxide, which has been created during operation.
Condenser
The electrostatic condenser collimates and focuses the ion beam.
Probe Currents
After passing the condenser, the beam current is defined by a set of software-controlled mechani-
cal apertures. By using the different apertures in combination with the different condenser set-
tings, the probe current can be continuously adjusted in the range between 1 pA and 100 nA.
Objective Lens
The objective lens is designed as an electrostatic Einzel-lens system. It focuses the beam onto the
specimen surface.
Instruction Manual ZEISS Crossbeam 550L, Crossbeam 550 | en-US | Rev. 3 | 349500-8122-000
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Summary of Contents for Crossbeam 550
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