Energy exchanges between atoms with a quartz crystal $\mu$-balance.

We propose an experimental method to fully characterize the energy exchange of particles during the physical vapor deposition process of thin surface layers. Our approach is based on the careful observation of perturbations of the oscillation frequency of a Quartz Crystal $\mu$-balance induced by the particles interaction. With this technique, it is possible to measure the momentum exchange of the atoms during the evaporation process and determine the ideal evaporation rate for an uniform energy distribution. We are able to follow the desorption dynamics of particles immediately after the first layers have been formed. These results are in close relation to the surface binding energy of the evaporated material, they offer a better control to obtain the desired properties of the thin surface layer. We applied our technique to investigate the physical vapor evaporation process for diverse elements, usually implemented in the development of film surface layers, such as Cu, W, Au, Gd and In, and confirm that our results are in agreement with measurements done previously with other techniques such as low-temperature photoluminescence.