  Although the wetting films are similar in many aspects to other thin liquid
films, there are some differences in their behavior, too. In contrast to soap
and emulsion films, whose surfaces are homogeneous, solid substrates of wetting
films are heterogeneous as a rule, unless special measures for their
homogenization are taken. Here we mean primarily heterogeneous distribution of
surface energy leading to existence of hydrophobic domains on hydrophilic
surfaces and vice versa. As is known, such hydrophobic domains could play the
role of gas-phase nucleation centers and it is widely accepted nowadays that
nano-bubbles can be formed there. The present paper reviews the effect of
nano-bubbles adhered at solid surface on stability of wetting films. It is
shown that the existence of nano-bubbles is crucial for the lifetime of wetting
films. Another peculiarity typical for hydrophobic solid surface, the so-called
slippage effect, is also investigated and its contribution to the dispersion
equation of capillary waves on wetting films is accounted for.
