Difference method for solution of the inverse problem of reflectometry of multilayer films

A schematic of a reflectometric experiment whose results make it possible to reconstruct the structure of multilayer films on substrates is proposed. A mathematical apparatus is developed that allows for determining the numerical values of the main parameters (electron density, thickness, and roughness) for each layer of the model film. Until now, there have been no methods for determining the structure of multilayer films from experimental data, and the problem has been solved by the trial-and-error method. Some model examples of reconstruction of the film structure are reported.