Characterization of ZnO and ZnO: Al thin films deposited by the sol–gel dip-coating technique
2008 (English)In: Thin Solid Films, ISSN 0040-6090, E-ISSN 1879-2731, Vol. 517, no 3, 1077-1080 p.Article in journal (Refereed) Published
Nanocrystalline zinc oxide films have been obtained by the sol–gel process. The films were deposited from precursor solutions by dip-coating on quartz substrates, and subsequently transformed into nanocrystalline pure or aluminium-doped ZnO films after a thermal treatment. The film microstructure and composition characterization was studied by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The optical properties were studied by transmittance spectroscopy. The water adsorption energy was measured by temperature programmed desorption (TPD) in the range 90–700 K. The optical transmittance in the UV region gives bandgap energy values of 3.27 eV for undoped samples, and higher than 3.30 eV for the Al-doped ones. The increase in bandgap energy in Al-doped samples may be explained by band-filling effects. The band edge absorption coefficient increases monotonically for the Al-doped samples but has a shoulder for the undoped ones, which may be assigned to room-temperature excitonic absorption.
Place, publisher, year, edition, pages
Elsevier, 2008. Vol. 517, no 3, 1077-1080 p.
Zinc oxide; Optical properties; Doping; Thin films; Sol–gel; Temperature programmed desorption
Engineering and Technology
IdentifiersURN: urn:nbn:se:liu:diva-103889DOI: 10.1016/j.tsf.2008.06.028OAI: oai:DiVA.org:liu-103889DiVA: diva2:692292