Displaying the results of an XPS Depth Profile Laura Blair

Outline of Presentation  Review of experiment  Problem Statement  What I Did  What the User has to Do  Key Features  Key Issues  Future Improvements  Demonstration of programs

X-Ray Photoelectron Spectroscopy (XPS) is used to evaluate the surface chemistry The Experiment One XPS method is acquiring elemental maps Bright regions indicate high intensity whereas dark regions indicate low intensity. Bright therefore lots of oxygen compared to surrounding Dark therefore less carbon here than in surrounding region

The Experiment Find sample – Hard disk. Collect elemental maps to determine the initial surface chemistry. Sputter the surface to remove the top nanometers (~5- 20nm). This is done using an ion gun which blasts the surface with ions. Different ion gun voltage settings are used to control how fast and how deep the sputtering occurs. Collect elemental maps to determine the surface chemistry after the first depth. Repeat until you have completed the depth profile through the coating – in this case it was 13 layers.

Problem Statement Problem: Current graphical user interface allows you to view only one image at a time. The depth profile conducted for this project resulted in 100+ images! Goal: Create a graphical user interface that would allow me to view a selection of the 100+ images at a time making it easier to interpret the results.

What I Did Wrote two programs and two functions to accomplish objective! First Program: Has one window. Has two text fields Buttons are element symbols

What I Did Second Program: Has twelve windows Buttons are element symbols and depth values. If element symbol selected the program displays up to 12 images of that element at different depths.

What I Did If depth selected the program displays up to 12 elements at that depth.

What I Did The two functions are used to extract out the element symbols and depth values from text files created by the user. The extracted information is used by the programs to create the buttons and label the images. These functions are key in ensuring the programs will work when different element symbols, depth values, number of elements or number of depths are analyzed.

What I Did – Template for depth text file # In the following text document you will need to enter # the number of depths and the values of each depth in nm # On the following line enter the total number of depths 14 # On the following lines enter the value of each depth in nm # only enter one value per line Role of the function: Strip out the comments Save depth values to an output file which is read by the programs

What the User has to Do Conduct a depth profile with maps collected after each sputter Open maps in Multipak and adjust endpoints as necessary Choose the export as tiff file menu option Create a folder directory in which each folder is labeled depthn. For example depth0-depth13 in the example Save the file as it’s elemental symbol in the appropriate folder. Create a depth text file or edit the template text file. Create an element text file or edit the template text file. Compile and run the programs

Key Features  Program resizes, crops and labels the images prior to display.  Program versatility – doesn’t have to be re- written for different depth profiles.  Displays images in a variety of ways allowing interpretation from different perspectives.  Checks to see if image exists before trying to display – doesn’t crash!  Able to display up to 24 depths and 24 elements.

Key Features Oxygen at depth 21 is displayed

Key Features Ar is element # 17!

Key Issues Program will open images 0-11 first so user won’t see image 13 if there is also an image 1  Elemental map collected at depth 0 for all 24 elements but only 12 displayed

Buttons don’t wrap around – if have 24 elements and 24 depths and some buttons will be off the screen! Key Issues

Future Improvements Add save option to the 12 image program so user can save display. Create a slider for the one image program. I created the text widgets so the user can look at an individual image but it would be nice if they could scroll through all of the images to determine which one to study.