SOFTWARE USEFUL FOR TRAINING STUDENTS IN ELECTRON PROBE MICROANALYSIS

Software has become an important part of training students in EPMA at UW-Madison. Specifically,

1. Monte Carlo (MC) programs serve several functions, providing rapid feedback for understanding spatial constraints of electrons hitting targets, relevant for understanding image creation and x-ray generation. I use David Joy's programs and more recently CASINO in the first week of my class. Joy has developed a useful set of exercises. CASINO expands upon the electron impact modelling and includes estimates of x-ray production both with depth and laterally, and provides the ability to model some aspects of thin films and vertical boundaries.

2. WinXray: Provides a MC simulation of what an EDS spectrum would look like for various conditions (different composition, keV, take off angle). Visualize effect of contamination on EDS detector window.

3. PENELOPE and PENEPMA: Originally developed by U. of Barcelona physicists to model radiation (e.g. therapy), this program provides two additional features to a MC simulation: any geometry can be modelled, and secondary fluorescence can be determined. Visualize incorrectly labelled diffusion (e.g., Ca in olivine).

4. GMRFilm: Permits modelling (forward and reverse) of thin films on substrates, including secondary fluorescence. Visualize effect of varying carbon coating thicknesses.

5. Virtual WDS: provide the ability to visualize various elemental peaks interfering with analytical lines or background positions. Teaches student to save instrument time by working out interferences and background positions beforehand.

CASINO, WinXray and PENEPMA provide estimates of x-ray intensities, so k-ratios can be estimated. Thus, thought experiments are possible, including demonstrating the effects of absorption and fluorescence in simple binaries. All are free or shareware except Virtual WDS. Most have nice GUIs, whereas others are command line driven (GMRFilm, PENEPMA). These are valuable tools which students take with them and use later in their research.