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The sources of non-uniformity in thin films produced using atomic layer deposition (ALD) have been investigated by reviewing the mechanical hardware of ALD reactors, precursors, and the by-products of surface reactions. The most common causes of non-uniformity are overlapping pulses, thermal self-decomposition of precursors, and non-uniform gas distribution. Less studied, however, are the consequences of downstream surface reactions of gaseous by-products. In particular, titanium nitride films have been found to be significantly less uniform than those of transition metal oxides deposited from metal halides. The influence of reaction by-products on the TiN film growth has been studied by comparing the deposition in the cross-flow and showerhead style reactors. Finally, the sources of non-uniformity in plasma enhanced (PE) ALD are illustrated by studying the TiN deposition process.

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The mass thickness of thin titanium oxide and hafnium oxide films grown by the atomic layer deposition method on silicon substrates was determined using EPMA data and STRATA and FLA programs. The results of the two programs coincided well if a set of relative intensities was measured at different energies of probe electrons. Comparative measurements by XRF gave higher values. Comparing the mass thicknesses of films measured by EPMA and absolute thicknesses determined by optical spectrophotometry, ellipsometry and profilometry, the densities of polycrystalline films were estimated. Values of 3.3±0.2 and 8.7±0.2 g cm−3 were obtained for TiO 2 anatase grown at 300 °C and monoclinic HfO 2 grown at 600 °C, respectively. Titanium oxide films deposited at 100 °C contained significant amounts of chlorine and hydroxyl groups (7.2±0.7 and 6.9±0.9 mass-%, respectively).had HfO 2 stripes on a silicon substrate. The film was deposited

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