%0 Journal Article %T ZnO Heteroepitaxy on Sapphire Using a Novel Buffer Layer of Titanium Oxide: Crystallographic Behavior %A Satoshi Yamauchi %A Yoh Imai %J Crystal Structure Theory and Applications %P 39-45 %@ 2169-2505 %D 2013 %I Scientific Research Publishing %R 10.4236/csta.2013.22006 %X A novel buffer layer consists of titanium oxide grown on a-sapphire by low-pressure chemical vapor deposition using titanum-tetra-iso-propoxide and oxygen gas was used for ZnO epitaxial growth at temperature as low as 340℃ by plasma-assisted epitaxy using radio-frequency oxygen-gas plasma. XRD and RHEED indicated (0001)Ti₂O₃ layer in corundum crystal system was epitaxially grown on the substrate in an in-plane relationship of [1-100]Ti₂O₃// [0001]Al₂O₃ by uniaxial phase-lock system. Growth behavior of ZnO layer was significantly dependent on the Ti₂O₃ buffer-layer thickness, for example, dense columnar ZnO-grains were grown on the buffer layer thinner than 10 nm but the hexagonal pyramid-like grains were formed on the thin buffer layers below 2 nm. RHEED observations showed ZnO layer including the pyramid-like grains was epitaxially grown with single-domain on the thin buffer layer of 0.8 nm in the in-plane relationship of [1-100]ZnO//[1-100]Ti₂O₃//[0001]Al₂O₃, whereas the multi-domain was included in ZnO layer on the buffer layer above 10 nm. %K ZnO %K Ti< %K sub> %K 2< %K /sub> %K O< %K sub> %K 3< %K /sub> %K Plasma-Assisted Epitaxy %K Hexagonal Pyramid Grain %U http://www.scirp.org/journal/PaperInformation.aspx?PaperID=33049