  Critical phenomena and universality behavior of ferromagnetic thin films
described by a spin-1 Blume-Capel Hamiltonian has been examined for various
thickness values ranging from 3 to 40 layers. Using effective field theory, we
have found that crystal field interactions significantly affects the critical
value of surface to bulk ratio of exchange interactions $R_{c}$ at which the
critical temperature becomes independent of film thickness $L$. Moreover, we
have extracted the shift exponent $\lambda$ from computed data. Based on the
results, we have shown that in the presence of surface exchange enhancement,
the system may exhibit a dimensional crossover. We have also found that
presence of crystal field interactions does not affect the value of $\lambda$.
Hence, a ferromagnetic spin-1/2 thin film is in the same universality class
with its spin-1 counterpart.
