More Practice and Filmetrics Interferometer

Today, we were going to practice more on floating of the PS films and checking the thickness of the films. We are going to learn how to use the Filmetrics Interferometer.
Everyone made two films for wrinkling analysis at Hasbrouck. An additional slide was made for X-ray reflectivity. We set up the X'Pert Pro for analysis for the thickness of the film. We made a quick video on placing the slide on the stage. As you can see, it takes a couple of tries sometimes for it to close correctly and then it must be raised or lowered, using a screwdriver, to get the proper count rate to start the analysis.

We left it running and went to Hasbrouck to perform the wrinkling.

We went through the usual procedure. Cut out film, float film, add 2 microliters to the center, take picture of whole film and zoom it and take picture of wrinkles. Go through all the increments and take pictures at each one. Each of us did our films, I messed up on one. When moving the film towards the middle to take the picture, I touch the top of the film instead of the side and it created wrinkles all over the film so I could not continuing using it. This is why we, or I, need practice on this procedure. Save the pictures of analysis.

In the afternoon, Ling Yang showed us how to use the Filmetrics Interferometer. This instrument uses reflection of light directed at the film so the light must bounce back. This would not happen if we used a glass slide so we used a piece of silicion sheet instead as our substrate. We broke off a piece of silicon and spin coated, at a slower speed since the interferometer needs a thicker film to analyze.

Once spin coated, we took it to the room with the interferometer but that one was not working so Ling Yang took us to her interferometer set up. She demonstrated how to calibrate the Filmetrics interferometer and how to focus the light. This is required to acquire accurate readings.


The thickness range for the Filmetrics is between 30 nm to 1mL which would be adequate for our thickness readings on our films. But, there is always a but, the X'Pert Pro gives much more accurate readings for thickness. And since were are comparing wrinkles and thickness, we want the most accurate readings possible.