Nitrogen flow rate dependence of the growth morphology of TiAlN films deposited by reactive sputtering

The dependence of the growth morphology of TiAlN films deposited by reactive sputtering on Si(100) substrates was investigated using scanning and transmission microscopy, X-ray diffraction and atomic microscopy. The TiAlN films deposited by this technique have the (200) preferred orientation of the NaCl structure. However, at lower nitrogen flow rates the (200) intensity peak in the XRD spectra decreases in intensity and broadens as an additional peak of 101̄1 wurtzite structure alloys overlaps at the same 2θ value. The TiAlN film has a columnar structure. The columns become denser as the nitrogen flow rate increases. Atomic force microscopy indicates a fluctuating surface morphology mainly arising from the grain domain distribution in a random fashion.