Phase stability and oxygen doping in the Cu-N-O system
2010 (English)In: Journal of Crystal Growth, ISSN 0022-0248, E-ISSN 1873-5002, Vol. 312, no 10, 1779-1784 p.Article in journal (Refereed) Published
A growth stability diagram for the system Cu-N-O has been determined in the temperature range 250-500°C for a thermally activated CVD process, based on copper (II) hexafluoroacetylacetonate (Cu(hfac)2), NH3 and H2O. Without any addition of water only Cu3N was obtained. Addition of water introduces oxygen into the Cu3N structure to a maximum amount of 9 atomic % at a water/nitrogen molar ratio of 0.36 at 325 °C. Above this molar ratio Cu2O starts to deposit in addition to an oxygen doped Cu3N phase. Only Cu2O is deposited at a large excess of water.
XPS and Raman spectroscopy indicated that the additional oxygen in the doped Cu3N structure occupies an interstitial position with a chemical environment similar to oxygen in Cu2O. The oxygen doping of the Cu3N phase did not influence the lattice parameter which was close to the bulk parameter of 3.814 Å. The film morphology varied markedly with both deposition temperature and water concentration in the vapour during deposition. Increasing the water concentration results in less faceted and textured films with smoother and more sphere like grains. The resistivity of the Cu3N films increased with increased oxygen content of the film and varied between 10-100 Ωcm (0 to 9 atomic% O). The optical band gap increased from 1.25 to 1.45 eV as the oxygen content increased (0 to 9 atomic %).
Place, publisher, year, edition, pages
North Holland: Elsevier , 2010. Vol. 312, no 10, 1779-1784 p.
A3. Metalorganic chemical vapour deposition, B2. copper (I) nitride, A1. Oxygen doping, A.1 Resistivity, A2. Band gap
Research subject Inorganic Chemistry
IdentifiersURN: urn:nbn:se:uu:diva-110525DOI: 10.1016/j.jcrysgro.2010.02.025ISI: 000277483100022OAI: oai:DiVA.org:uu-110525DiVA: diva2:277187