ИСТИНА

The multi-step reactions mechanism of F atoms interaction with SiOCH low-k dielectrics films, developed on the base of the measured evolution of various surface groups (e.g. Si-CH3) and systematic DFT quantum mechanical calculations, was incorporated into 3D Monte Carlo model of the etching and damage processes. The model is realized on 3D model maps of porous films and allows us to obtain as 3-D images at every moment of the etching process of porous films so a layer by layer distribution of the components that are formed during the etching. Comparison of the calculated etching rates of SiOx matrix by fluorine atoms with the experimental data is used to determine the effective etching probabilities (reciprocal values of F atoms collisions with SiOx matrix groups that are required to remove one group). The obtained detailed space-resolved dynamics of etching and damage processes for low-k films with different parameters (porosity, pore and inter-pore channels sizes, dielectric permittivity) can be of interest for plasma processing technology