Thin films of silica-alumina were prepared by argon ion beam sputter deposition on gold foil using different HY-zeolites as targets. X-ray photoelectron spectroscopy (XPS) results on thin films (< 10 nm) revealed that the Si/Al ratio in the films initially decreases with deposition time, but later becomes very similar to that of the target zeolite. Similarly, the position of O 1s, Al 2p, Si 2p peaks converged to the binding energies for zeolite target used. Based on the line shape of the O KVV Auger transition, we find that there is no segregation of silica and alumina in the films. By scanning electron microscopy (SEM) and scanning Auger electron spectroscopy (SAE) the thin films appear homogeneous. X-ray diffraction (XRD) results on thicker films (~ 1 µm) indicate that the silica-alumina layers are amorphous.