optimization procedure

questex19.in : optimization procedure

Requires: QUEST, OPTIMIZER Minimum Versions: QUEST 2.0.2.R

This example can be used as a tutorial for setting up an optimization procedure with a so-called curved target. This example is based on questex14.in

Running the Example

An experimental profile is provided with the example in a simple XY format which can be read into the OPTIMIZER questex19.opt.

To load and run this example, select the Load example button in DeckBuild. This will copy the input file, GDSII file and results to your current working directory. Select the run button to execute the example.

The goal of the example is to find Metal1 Thickness and conductivity that will give a Q factor versus frequency close to the experimental one. To achieve this, select Optimizer... from the Main Control menu. The DeckBuild: Optimizer screen will appear in a moment.

First, select Parameters from the Mode menu; this will display the Parameter worksheet. To define the parameters, select (highlight) the MATERIAL name = "m1" statement from the input deck and choose Add from the Edit pulldown menu. The Parameter define popup will appear. Check cond, then press Apply. Redo the same thing with the DEPOSIT deposit type = "metal" layername = "M1" statement and select thick. By default all min/max values for parameters are +-50%. To edit any of these numeric values position the pointer over the corresponding cell of the worksheet, click the left-hand mouse button, edit the value, and do not forget to press return after finishing the editing. You should change the default +-50% in this case. Set Minimum value of the conductivity to 1e+06 and maximum to 1e+08 and Minimum value for thickness to 0.25 and Maximum to 1.

The next step is setting the curved target. Select Targets from the Mode menu. Highlight the extract name="simu" line. This line extracts the Q factor verus frequency. Choose Add from the Edit pulldown menu. A new row will be inserted into the Target worksheet. The target name will correspond to the name in the extract statement. To insert a curved target select the only row in the worksheet by double-clicking the left-hand button while the pointer is positioned anywhere in the row, then choose From File from the Insert submenu from the X/Y Data menu under the Edit pulldown menu. As the result the Optimizer X/Y Target Data popup will appear. Select questex19.opt file and then press Load.

Once the parameters, targets, and setup information have been defined, the Optimization process can be started by pressing the Optimize button. During the optimization run, the Graphics mode shows real-time updates of parameter, target, and error values.

Results analysis

After optimization is completed you may execute the tonyplot command which will plot the comparison between optimized and measured profiles.