waferstage

This mode describes the SIRE-3 Wafer Stage. This machine served as a prototype for a whole generation of wafer steppers (PAS-2500, PAS-2500) that where produced by the ASML company in the late 80's and early 90's. An extensive description of this machine and the modeling and simulation is described in the Getting Started section.

You can load and view this model in the Editor by loading the model WaferStage.em.

If you start the Simulator (the experiment WaferStage.exp is automatically loaded) you can see a 3D Animation of the machine. The model is fairly complex. To get the optimal performance out of your computer, use Brute force calculation:

Select the Brute Force command from the Simulation menu.

Now a simulation run will be calculated in the background. When the run is finished, the results will be shown in the plot window.

Select the Replay - 3D Animation command from the Simulation menu.

Now the Animation will be shown in real time, i.e. frames that cannot be calculated within a given time, will be skipped. The main plot will show the position of the chuck with respect to the granite base.

As you can see the errors damp out quickly after the motion stops. You can try to run other motion profiles to see if that influences the position errors.

Experienced control engineers are challenged to linearize the model at various configurations. This can easily be done in 20-sim by performing a simulation run and linearizing at the end of the run. The picture below shows the frequency response that resulted after several runs (profile_y\x = 0, profile_x\x = 0, 0.005, 0.01 , .. 0.025 m) and linearization from controller\sp_y to P\y. As one would expect, the frequency response varies with the position of the load.

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