  A Green's function formalism is used to calculate the spectrum of localized
modes of an impurity layer implanted within a ferromagnetic thin film. The
equations of motion for the Green's functions are determined in the framework
of the Ising model in a transverse field. We show that depending on the
thickness, exchange and effective field parameters, there is a ``crossover''
effect between the surface modes and impurity localized modes. For thicker
films the results show that the degeneracy of the surface modes can be lifted
by the presence of an impurity layer.
