If an atom in an intrinsic semiconductor (SC) is excited thermally so an electron jumps from the valence band to the conduction band, then the electron is free and the atom becomes a positive ion. This is called a hole. If an electric field is applied across the material, free electrons will drift to carry a current. If a free electron created elsewhere in the lattice collides with the hole they recombine into a neutral atom--but there is a hole left where that electron came from. It looks like holes drift too, opposite to the electrons. Because they are charged positively, they also contribute to carrying current. Notice that the ion itself doesn't move, because it is bound in the crystal lattice. It's the hole that moves. That's the difference.
I am new to XPS Data analysis, and I have a .sle file that I got out of XPS Machine Software, and I am using CasaXPS to analyse the data. This software takes only .vms files. I want to convert the .sle to a .vms file for analysis. How or where can I do this? Any help on this will be deeply appreciated.