Zeiss GeminiSEM Series Instruction Manual

Also see for GeminiSEM Series: Instruction manual

5 Commissioning and First Operating Steps | 5.5 Modifying Gun Parameters ZEISS7. Deactivate the Touch Alarm Disable checkbox.INFO: The Touch Alarm Disable option connects the stage potential with low impedanceto the ground. This may be required with the usage of micromanipulators. Activating thischeckbox disables both, touch alarm and specimen current measurement.à This activates the touch alarm that helps to avoid collisions of the stage.8. Move the stage to the position of the Faraday cup.9. Acquire an image of the Faraday cup.10. Activate the Spot checkbox.à Green crosshairs are displayed on the image. This crosshairs indicate the position of thebeam spot.11. Grab the crosshairs and move them into the hole of the Faraday cup.à The probe current is measured continuously.à The measured probe current is displayed inthe Specimen I readout.5.5.5 Changing the Extractor VoltageThe Extractor voltage is preset by the factory or by the ZEISS service representative. Within certainlimits, the operator may carefully increase the extractor voltage in order to optimize the probecurrent for particular applications.InfoUse a Faraday cup to measure the probe current when changing the extractor voltage.InfoThe newly set extractor value is only valid for the current work session. After a restart of theSmartSEM software, the microscope restores the nominal extractor voltage.InfoReducing the extractor voltage may impair the performance and resolution of the microscope.4 Avoid reducing the extractor voltage.4 If at all, reduce the extractor voltage only for a short time (1–2 h) and by maximum 500 V.Prerequisite ü The user privilege Extractor is required to change the extractor voltage.Procedure 1. From the Menu Bar, select Beam > Gun Setup.à The Gun Service dialog is displayed.2. To increase the extractor voltage, double-click the Extractor V Target readout.à The Extractor V Target window is displayed.3. Enter a higher value.4. Click OK.88 Instruction Manual ZEISS GeminiSEM series | en-US | Rev. 2 | 349500-8138-000