Maintenance of EB Tungsten Filament of SEM

SEM (scanning electron microscope) of the electron microscope has a lower degree of vacuum, and a large beam current. Therefore, the life time of tungsten filament of SEM is limited. Generally speaking, it can last for only a few dozen hours. The life time of tungsten filament of SEM has a direct impact on the cost of the instruments operation and the effective time of operation. Consequently, it would cause more pollution and other adverse consequences. Therefore, the tungsten filament of SEM needs a regular maintenance or repair. Users can take the following measures to maintain tungsten filament and extend the life time of instruments.

Firstly, check the condition of tungsten filament, if possible, users should put the component of tungsten filament on the dissecting microscope to check again. The rate of evaporation of the filament surface is related to the temperature of the filament, users can adjust a higher height to decrease the temperature of the filament. The material can choose a thick filament gasket. And then users should adjust the current of tungsten filament. During the maintenance of tungsten filament of SEM, users should check the saturation of the filament timely. Under an unsaturated condition, current of tungsten filament should be adjusted to the saturated condition. Finally, keep the vacuum degree of Scanning electron microscope lens.

Other measures to maintain tungsten filament of SEM are: 1. Before exchange the filament, users should remove dampness and air of the new filament. 2. Do not switch filament frequently in the daily work.

• < Prev
• Next >