Average Drift Speed Monitoring

Requirement:

The On-Line SVT Monitoring system monitors the average drift speed on all SVT detectors.

Justification:

The drift speed should ideally constant with an accuracy of 0.1 %. In practice, variations may arise from temperature fluctuations or biasing perturbations. It is essential to monitor the changes in the drift speed as they arise. Measurements of the average drift speed will be performed periodically using charge injection at the different precisely known locations on all wafers of the SVT. It is the job of the monitor to check that the drift speeds on all wafers are constants or within tolerances.

Requirement:

The On-Line SVT Monitoring system provides displays of the measured drift speed average and width on all wafers. There should be multiple ways to view the data:

• Wafer by Wafer Mode
  
• Multi-wafer Mode
  
• Graphical Multi-channel Mode
  

Justification:

It is necessary the operator can visualize the output of that calibration process.

Requirement:

The operator can set tolerance limits on the minimum and maximum drift speed average and width determined by the calibration process after charge injection measurements.

Justification:

These tolerances will be used as the basis for alarm generation.

Requirement:

Yellow Alarm is generated when the drift speed on one wafer exceeds tolerances.