  The properties of the QCD partition function at finite chemical potential are
studied within the instanton liquid model. It is shown that the density
dependence of the quark-induced instanton-antiinstanton (I-A) interaction leads
to the formation of topologically neutral I-A pairs ('molecules'), resulting in
a first order chiral phase transition at a critical chemical potential
$\mu_q^c\simeq 310$ MeV. At somewhat higher densities ($\mu_q\ge360$ MeV), the
quark Fermi surface becomes instable with respect to diquark condensation
(Cooper pairs) generating BCS-type energy gaps of order 50 MeV.
