94
CHAPTER 4:
Basic Operation
Model CRX-6.5K Probe Station
4.4.2 Evacuating the
Vacuum Chamber
After closing the vacuum chamber lid, follow this procedure to evacuate the system.
This process assumes that the vacuum pump is off when beginning.
1. Use the z-axis micrometers to raise all probes 3 mm to 4 mm above the sample.
Failure to do so will potentially cause damage to the probe tip or scratch the sam-
ple surface.
2. Close the purge valve completely (FIGURE 4-9).
3. Verify that the vacuum pump is turned off and properly vented (close the manual
vent valve).
4. Open the vacuum isolation valve completely (FIGURE 4-9).
5. Start the turbo pumping system. If you are using the TPS-FRG, turn on the power
switch located on the rear of the unit. The gauge will automatically turn on when
the pressure reaches approximately 10
-3
Torr.
6. Observe to be sure it starts rotating up to its maximum operational speed.
The flexible stainless steel vacuum line should immediately begin to stiffen. The
vacuum gauge should begin reading in approximately 3 min. The turbo pump should
reach full speed in approximately 5 min. The chamber should pump below <10
-3
Torr
in approximately 30 to 60 min. If it does not, refer to section 6.3.1.8 for
troubleshooting. At this point in the process, operation of the vacuum pump and
isolation valve are dependent on the intended application.
4.4.3 Shutting Down
the Turbo Pump
Follow this procedure to shut down the turbo pumping system. This procedure
assumes that the system is sealed and under vacuum.
1. Close the vacuum isolation valve.
2. Turn off the turbo pumping system. If you are using the TPS-FRG, simply turn off
the main switch on the rear of the unit.
3. Open the manual vent valve located on the side of the turbo pump to vent the
turbo pumping system. In order to increase the lifetime of the turbo pump, it is
always recommended to vent the pumping system through the manual vent
valve and not simply allow atmospheric air to rush into the inlet.
4. You will hear hissing as the manual vent valve is opened and air rushes into the
turbo pump. Once the hissing ceases, completely close the manual
vent valve.
Remember you will always need to purge the vacuum chamber and open the vacuum
isolation valve before restarting the pump.
FIGURE 4-9
Left: Purge valve; Right: Vacuum isolation valve
Содержание CRX-6.5K
Страница 4: ...Model CRX 6 5K Probe Station ...
Страница 52: ...42 CHAPTER 2 System Overview Model CRX 6 5K Probe Station ...
Страница 92: ...82 CHAPTER 3 Installation and Setup Model CRX 6 5K Probe Station ...
Страница 162: ...152 CHAPTER 6 Maintenance and Troubleshooting Model CRX 6 5K Probe Station ...
Страница 166: ...156 INDEX Model CRX 6 5K Probe Station ...