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Thin films and nanotubes of iron oxide have been successfully deposited using atomic layer deposition (ALD) on Si (100) and anodic aluminium oxide (AAO). Ferrocene Fe(Cp)2 and oxygen are used as precursors. Results from the quartz crystal micro balance (QCM) investigation showed that the process exhibited ALD characteristics. Depositions were carried out in the temperature region of 350 °C to 600 °C on Si (100). All depositions on AAO were made at 400 °C. The growth per cycle values were around 0.14 nm on Si (100) in the temperature region of 350 °C to 500°C and 0.06 nm on AAO. GIXRD showed that below 500 °C the iron oxide crystallised as a phase mixture on Si (100) and the same phase mixture was also obtained on the AAO substrates. One of the phases was identified as the rhombohedral Fe2O3 phase (hematite), but the second phase could not be unambiguously identified. Above 500 °C only phase pure hematite was detected. XPS analysis showed a carbon contamination level of around 1 atomic percent in all the deposited films except for the films deposited at the lowest deposition temperature, 350 °C, where the carbon concentration were about 3 atomic percent. For deposition of nanotubes both commercial and in-house made AAO membranes were used, having aspect ratios of 200 and 30, respectively. By etching of the in-house made AAO membranes after deposition, free-standing nanotubes retaining the order of the template could be fabricated. |