6533b859fe1ef96bd12b7f34
RESEARCH PRODUCT
Optical Spectra and Direct Optical Transitions in Amorphous and Crystalline ZnO Thin Films and Powders
Ilze AulikaAlexandr DejnekaMarina MakarovaDagmar ChvostovaA. ChurpitaV. A. TrepakovV. A. TrepakovLubomir JastrabikZdeněk Hubičkasubject
Materials scienceFabricationRenewable Energy Sustainability and the EnvironmentBand gapbusiness.industryNanotechnologyCondensed Matter PhysicsNanocrystalline materialOptical spectraSurfaces Coatings and FilmsElectronic Optical and Magnetic MaterialsAmorphous solidMaterials ChemistryElectrochemistryOptoelectronicsParticle sizeThin filmAbsorption (electromagnetic radiation)businessdescription
Comparative studies of ZnO crystalline and amorphous thin films and nanocrystalline powders are reported. The UV-visible optical spectra were analyzed with special attention paid to the direct optical bandgap. Atmospheric radio-frequency barrier torch discharge and pulsed hollow cathode sputtering techniques for the film fabrication were used. For the crystalline films, similar values of the direct optical bandgap were found independent of the growth method used. The analysis of the amorphous films and powders revealed a pronounced Urbach-like exponential absorption tail approaching the bandedge. For the powders, the bandgap energies were larger than those for the crystalline and amorphous films. A decrease in the powder particle size in the powders leads to an increased direct optical bandgap.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2010-01-01 | Journal of The Electrochemical Society |