A study on zinc oxide, aluminum oxide, and aluminum doped zinc oxide thin films grown by LPMOCVD technique; growth and characterization

Low pressure chemical vapor deposition of zinc oxide, aluminum oxide, and aluminum doped zinc oxide films has been investigated. Zinc acetate and aluminum acetylacetonate were used as zinc and aluminum sources, respectively. These organometallic compounds were proved to be excellent source materials for a CVD process. H{dollar}sb2{dollar}O, N{dollar}sb2{dollar}O, O{dollar}sb2{dollar}, and air have been used as secondary reagents in this study. Only H{dollar}sb2{dollar}O promoted full decomposition of the organometallic source and produced high quality oxide films.; Microstructures of the ZnO films grown with N{dollar}sb2{dollar}O, O{dollar}sb2{dollar}, and without any oxygen source were all amorphous. X-ray photoelectron spectroscopy and Auger electron spectroscopy results showed that these films contained large amount of carbon. The film structure became crystalline and the amount of carbon impurities decreased as H{dollar}sb2{dollar}O was introduced to the reactor. X-ray diffraction patterns of ZnO films using 15 SCCM of Ar gas flow through a water bubbler showed only a (002) peak (c-axis planes parallel to the substrate surface) with some trace of a (101) peak. The (002) peak intensity was dependent on deposition temperature.; Amorphous Al{dollar}sb2{dollar}O{dollar}sb3{dollar} films were grown on Si(100) and glass substrates. Water vapor played an important role in the film growth kinetics, film purity, and surface morphology of the grown films. Without any water vapor, the deposition rate was very low and grown films contained large amounts of carbon due to incomplete decomposition of aluminum acetylacetonate. High water vapor pressures produced ligand-free pure aluminum oxide films with a smooth surface even at a substrate temperature of 230{dollar}spcirc{dollar}C. The activation energy of the Al{dollar}sb2{dollar}O{dollar}sb3{dollar} film deposition was obtained as 17.3 kJ/mole.; Al doped ZnO films have been grown on glass and ZrO substrates by using zinc acetate, aluminum acetylacetonate, and water vapor for the first time. The aluminum concentration within doped films was measured by an electron microprobe. The Al/Zn atomic ratio within the films increased as the Al source temperature increased. The crystal orientation of the films was dependent on the deposition temperature and the Al concentration within the films. The film resistivity was also affected by the deposition temperature and the Al source temperature. For the film deposited at 410{dollar}spcirc{dollar}C for 30 minutes with the Al source temperature at 100{dollar}spcirc{dollar}C, the resistivity was as low as 5.5 {dollar}times{dollar} 10{dollar}sp{lcub}-3{rcub}{dollar} {dollar}Omegacdot{dollar}cm.