10.2 Starting Duoplasmatron source from tuning soft

The Tuning Duo Source control panels allow the operator to set the Duo Source High Voltage, Arc current and coil current. The Duo Source High Voltage (or Accel HV) is chosen by the user according to analytical requirements. Both the Arc and the coil currents are not depending upon this accelerating High Voltage.

It is also possible to modify the source parameters from the synoptics panel.

10.2.1 The Duo source Start Process

The Duo source Start Process is activated in 2 cases:

- When the operator clicks START in the Duo source Start/Stop panel shown below.

- When a new ISF is loaded, if the new ISF accel HV is not the current one.

Any Duo source Start Process can be defined by the set of 3 initial parameters and 3 final parameters

Initial Duo HV	Final Duo HV
Initial Arc current	Final Arc current
Initial Coil current	Final Coil current

The initial parameters are the instrument current parameters. The final parameters may be the last saved parameters in Set-Up or the parameters saved in ISF file to load.

The usual currents value for a Duo source with an Duo High Voltage of 15kV is about:

◆ Arc current = 50 mA

Coil current = 250 mA

After a certain period of using the source, if the debit current of the primary beam is unstable or the plasma in the duo source is not maintain correctly, it is necessary to clean inside the source. This step will be described at the end of this manual.

10.2.2 The Duo source Start/Stop panel

Clicking the icon in the top of the Tuning menu bar opens the property box displayed below:

Select the Duo tab.

Duo source Starting Mode

- Analogic/digital Selection radiobutton. If Analogic, the source parameters are displayed the box in physical units (Volts or mA). If Digital they are displayed in no-unit digits, as they are displayed in the Real Time Screen.

ON Source Accel displays the accel HV as it is in the current ISF.

ON Arc Source displays the Arc current as it was at the last Stop Source.

ON Coil current displays the coil current as it was at the last Stop Source.

➢ Stop button for activating the Duo source Stop process.

➢ Start button opens Heating Source & Working panel displayed on the left-hand side for selecting the Duo source Starting Mode.

Note that start source is automatically performed by following procedure.

Source Heating & Working:

- Duo source chamber valve (EP1) is opened (if closed).

- Duo source is started (Accel HV, Arc current, Coil current)

- Source Heating only:

- Duo source is started (Accel HV, Arc current, Coil current) without changing the duo valve status.

➢ Pause button suspends either the Stop or the Start process.

Close closes Start/Stop sources Panel.

10.2.3 Duo source differed stopping and starting

• @>Stop button opens All Stop Sources panel displayed on the left-hand side. This panel allows to program the stopping the sources:

  • Source selection: Cs/Duo/NEG.
  • Duo source position: At Home/At Work.
  • Stopping date & time.
  • then, Apply and Close.

• @>Start button opens Differed starting for source Duo panel displayed on the left-hand side. This panel allows to program the starting of the sources:

  • ISF file selection: set Duo source Accel HV, Arc current and Coil current to start.
  • Selection of the Duo source starting Mode:
    • Source Heating & Working.
    • Source Heating only. (see above for the details)
  • then, Apply and Close.