Infrared reflection absorption spectroscopy (IRAS) was used to study the molecular alignment of the ferroelectric liquid crystal material, (S)-4-(α-methylheptyloxy)-4′-(4″-n-octylphenyl-oxycarbonyl)biphenyl (MHOPOB), on a highly-purity polyvinylalcohol (PVA) film. The molecular alignment was characterized as a function of the temperature and the thickness of the liquid crystal. For the film of 200nm in thickness, the molecules in the chiral smectic C phase (SmC*) were aligned with their long axes perpendicular rather than parallel with respect to the PVA substrate surface. This alignment was found to disappear at the isotropic phase temperature. A similar molecular alignment was observed for a 20nm-thick MHOPOB film in the SmC* phase, but the detailed alignment was different from that in the 200nm-thick film. This alignment in the SmC* phase was sustained even at the isotropic temperature in contrast to the 200nm-thick film, suggesting a short-range interaction between the PVA film surface and MHOPOB molecules. An experimental support for this short-range interaction is furnished by our polarization modulation IRAS measurements. The effect of PVA rubbing on the alignment is also discussed.