Selective growth of iron oxide thin films using the combined method of metal-organic chemical vapor deposition and microcontact printing

The authors have carried out the selective deposition of magnetite iron oxide (Fe3 O4) thin films with about 50 nm thickness on Si(100) surfaces which were patterned by octadecyltrichlorosilane (OTS) using microcontact printing (μCP) method. The μCP method showed that hydrophobic patterns with microdimension were able to be formed on hydrophilic area such as silicon surface. Iron oxide thin films were deposited on the Si(100) substrates by thermal metal-organic chemical vapor deposition (MOCVD) method using single molecular organometallic precursor of iron pentacarbonly [Fe (CO)5] with high purity (99.999%) oxygen gas. The deposition was performed in the range of 250-350 °C substrate temperature for 2-10 min under 1× 10-2 Torr in a homemade MOCVD system. In order to check the selectivity of as-deposited thin films optical microscopy, scanning electron microscopy, and atomic force microscopy analyses were performed. To confirm the crystallinity of deposited thin films, x-ray diffraction patterns and micro-Raman were studied. Also energy dispersive x-ray and x-ray photoelectron spectrometry results showed the composition of the as-grown iron oxide thin films. By means of these results, the authors can suggest the selective deposition mechanisms and tendencies of iron oxide thin films onto the OTS patterned Si(100) surfaces.