INFICON Maxtek PM-700 Plating Monitor - Manual (Page 30)

PM-700 SERIES PLATING MONITOR
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4.4.1.2 Electrolytic plating
Because the Preplate State is not necessary in the Electrolytic plating mode, the
Preplate button is ignored and only four different monitor states are defined for
this operating mode.
4.4.1.2.1 Ready State
In the Ready state plating rate and thickness are being monitored but the crystal
electrode current is zero so no plating will be occurring. The Ready State is
entered on power ON and also by pressing the Stop button. Pressing the Plate or
Deplate buttons steps the monitor from the Ready State into the selected state.
4.4.1.2.2 Plate State
The Plate State is entered from the Ready State by pressing the Plate button.
During the Plate state the crystal electrode current is set at the value required to
achieve a plating current density equal to that programmed in the Current Density
parameter. In addition, the indicated thickness is compared with the Endpoint
parameter. When the indicated thickness equals or exceeds the Endpoint
parameter, the monitor steps to the Endpoint State.
4.4.1.2.3 Deplate State
The Deplate State is entered from the Ready State or the Endpoint State by
pressing the Deplate button. In this state the crystal electrode current is adjusted
by the monitor as required to achieve the de-plating rate specified by the Deplate
Rate parameter. The Deplate State can be exited to the Ready State by pressing
the Stop button, or to the Plate State by pressing the Plate button. The Deplate
State is automatically terminated to the Ready State if the crystal health increases
to 95% or more.
4.4.1.2.4 Endpoint State
The Endpoint State is automatically entered from the Plate State when the
indicated thickness equals or exceeds the Endpoint parameter value. Pressing the
Stop or Deplate buttons steps the monitor from the Endpoint State to the Ready or
Deplate state. The Plate button is ignored while in the Endpoint State.
4.4.2 Monitor Measurement Modes
4.4.2.1 Single Probe Measurement Modes
The following three measurement modes require only one probe and can be
utilized on any of the PM-700 series of monitors.
4.4.2.1.1 Continuous
In this mode the bath is monitored continuously. Should the Probe fail during the
Preplate, Plate or Deplate state, the failure is enunciated, the Rate Display is held
at its most recent value, and the displayed Thickness is increased at the displayed
rate to indicate the best guess for the substrate thickness buildup.