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Atomic layer deposition ͑ALD͒ of TiO 2 films from tetrakis͑dimethylamido͒ titanium ͑TDMAT͒ or titanium tetraisopropoxide ͑TTIP͒ precursors was investigated. The growth kinetics, chemical composition, and crystallization behavior of the TiO 2 films were compared for combinations of the two precursors with three different sources of oxygen ͓thermal ALD using H 2 O and plasma-enhanced ALD ͑PEALD͒ using H 2 O or O 2 plasma͔. For TDMAT, the growth rate per cycle ͑GPC͒ decreased with increasing temperature; while for TTIP with either water plasma or O 2 plasma, a relatively constant growth rate per cycle was observed as a function of substrate temperature. It was found that the crystallization temperature of the TiO 2 films depends both on film thickness and on the deposition conditions. A correlation was observed between the TiO 2 crystallization temperature and the C impurity concentration in the film. The TiO 2 films grown using a H 2 O plasma exhibit the lowest crystallization temperature and have no detectable C impurities. In situ X-ray diffraction measurements were used to test the diffusion barrier properties of the TiO 2 layers and proved that all TiO 2 films grown using either H 2 O or O 2 plasma are dense and continuous.

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Vanadium pentoxide was deposited by atomic layer deposition (ALD) from vanadyl-tri-isopropoxide (VTIP). Water or oxygen was used as a reactive gas in thermal and plasma-enhanced (PE) processes. For PE ALD, there was a wide ALD temperature window from 50 to 200°C . Above 200°C , VTIP decomposed thermally, resulting in the chemical vapor deposition (CVD) of vanadium pentoxide. The PE ALD reactions saturated much faster than during thermal ALD, leading to a growth rate of approximately 0.7 Å/cycle during PE ALD using normalH2O or normalO2 . Optical emission spectroscopy showed combustion-like reactions during the plasma step. X-ray diffraction was performed to determine the crystallinity of the films after deposition and after postannealing under He or normalO2 atmosphere. Films grown with CVD at 300°C and PE normalO2 ALD at 150°C were (001)-oriented normalV2normalO5 as deposited, while thermal and PE normalH2O ALD films grown at 150°C were amorphous as deposited. The crystallinity of the PE normalO2 ALD could be correlated to its high purity, while the other films had significant carbon contamination, as shown by X-ray photoelectron spectroscopy. Annealing under He led to oxygen-deficient films, while all samples eventually crystallized into normalV2normalO5 under normalO2 .

Platinum thin films were grown by plasma-enhanced atomic layer deposition (PEALD) using (methylcyclopentadienyl)-trimethylplatinum (MeCpPtMe3) as precursor and respectively an oxygen, nitrogen and ammonia plasma as reactant. For each process the film thickness was found to be linearly dependent on the number of reaction cycles. Saturation curves and temperature windows were defined and growth rates of 0.45 Å cycle−1, 0.30 Å cycle−1 and 0.40 Å cycle−1 were obtained for the oxygen, nitrogen and ammonia process respectively. All the films were metallic platinum, crystalline, uniform and closed, with low surface roughness and low impurity levels. At a pressure of 1 × 10−3 mbar, nucleation on SiO2 was remarkably faster with the NH3 and N2 processes than with the O2 process. In-situ OES and MS measurements showed a fundamental difference between the NH3 and N2 processes and the O2 process. Based on these measurements we propose a reaction mechanism for the N2 and NH3 PEALD processes where nitrogen will unstably adsorb on the substrate during the plasma pulse and be used during the subsequent precursor pulse to remove part of the precursor ligands.