  We investigate magnetic and superconducting properties of layered
$f$-electron superlattices within the fluctuation exchange approximation
(FLEX). We show that spin fluctuations, which are characterized by the maximum
value of the spin susceptibility in the 3-dimensional (3D) Brillouin zone, are
strongly suppressed in $f$-electron superlattices. However, effective 2D spin
fluctuations can be increased due to the spatial confinement of the
$f$-electrons. Therefore, the tendency towards $d_{x^2-y^2}$-wave
superconductivity, mediated by these spin fluctuations, can be strongly
increased in $f$-electron-superlattices. This is in sharp contrast to
superlattices composed of conventional $s$-wave superconductors, where
superconductivity is generally suppressed.
