  A brief survey of fermion localization mechanism on a domain wall ("thick
brane") generated by a topologically nontrivial vacuum configuration of scalar
fields is given. The extension of scalar fields interaction with fermions which
supplies fermions with an axial mass is proposed. For several flavors and
generations of fermions this extension can entail the Cabibbo-Kobayashi-Maskawa
matrix of the Standard Model. As well the model with two scalar doublets which
provide a supplementary CP violation mechanism is considered.
