The effect of substrate temperature on atomic layer deposited zinc tin oxide
2015 (English)In: Thin Solid Films, ISSN 0040-6090, E-ISSN 1879-2731, Vol. 586, 82-87 p.Article in journal (Refereed) Published
Zinc tin oxide (ZTO) thin films were deposited on glass substrates by atomic layer deposition (ALD), and the film properties were investigated for varying deposition temperatures in the range of 90 to 180 degrees C. It was found that the [Sn]/([Sn] + [Zn]) composition is only slightly temperature dependent, while properties such as growth rate, film density, material structure and band gap are more strongly affected. The growth rate dependence on deposition temperature varies with the relative number of zinc or tin containing precursor pulses and it correlates with the growth rate behavior of pure ZnO and SnOx ALD. In contrast to the pure ZnO phase, the density of the mixed ZTO films is found to depend on the deposition temperature and it increases linearly with about 1 g/cm(3) in total over the investigated range. Characterization by transmission electron microscopy suggests that zinc rich ZTO films contain small (similar to 10 nm) ZnO or ZnO(Sn) crystallites embedded in an amorphous matrix, and that these crystallites increase in size with increasing zinc content and deposition temperature. These crystallites are small enough for quantum confinement effects to reduce the optical band gap of the ZTO films as they grow in size with increasing deposition temperature.
Place, publisher, year, edition, pages
2015. Vol. 586, 82-87 p.
Zinc tin oxide (ZTO), Atomic layer deposition (ALD), Buffer layer, Mixed oxide, Thin film photovoltaics, Optical band gap
Condensed Matter Physics Engineering and Technology
IdentifiersURN: urn:nbn:se:uu:diva-255039DOI: 10.1016/j.tsf.2015.04.029ISI: 000353984000014OAI: oai:DiVA.org:uu-255039DiVA: diva2:825198