Zeiss EVO - Page 98

5 First Operating Steps | 5.7 Working with Specific Specimen Types ZEISS
Recommended
Parameters
The following parameters are recommended for hydrated specimens. The values given are only
suggestions and the operator may find that different values will give better information for the
types of specimens that are being investigated.
Parameter EP mode for cooled hy-
drated specimens
EP mode for hydrated
specimens
EHT 20kV 20kV
I Probe 300pA 300pA
WD 8.5mm 5mm
Filament Fil I set to second peak Fil I set to second peak
Mid-column aperture 750μm 750μm
Pressure-limiting aperture 100μm EP aperture 100μm EP aperture
Beamsleeve aperture 500μm 500μm
Detector BSD or C2DX BSD or C2DX
Scanning parameters Cycle time ≥ 20s Cycle time ≥ 20s
Chamber pressure 650 Pa to slow dehydration 2500Pa to 3000Pa to retain
water at ambient tempera-
ture (20°C to 30°C)
Temperature Temperature of the speci-
men to retain water at
650Pa=1°C (controlled by
the Peltier coolstage)
–
5.7.3.1 Installing or Deinstalling the EP and Beemsleeve Apertures
To use the optional EP mode, you need to install the EP and beamsleeve pressure-limiting aper-
tures under the objective lens.
Additionally, you need to select the 750μm mid-column aperture and adjust some settings in
SmartSEM.
Pressure-limiting aperture mid-column aperture
None (HV mode) 20μm or 30μm
100μm EP aperture
and 500μm or 1000μm beamsleeve aper-
ture
750μm
Parts and Tools
 100μm EP aperture (upper aperture assembly, 354720-9309-000)
 Beamsleave aperture 500μm (lower aperture assembly, 354720-0266-000), recommended
 Beamsleave aperture 1000μm (lower aperture assembly, 354720-0267-000), alternatively
 Aperture removal tool (350700-0692-000)
 Upper aperture tool (354720-9310-009)
 Lower aperture tool (354720-9297-009)
98 Instruction Manual ZEISS EVO | en-US | Rev. 10 | 354706-0780-006