TY - JOUR
T1 - Influence of post-deposition annealing on electrical and optical properties of ZnO-based TCOs deposited at room temperature
AU - Lyubchyk, Andriy
AU - Vicente, António
AU - Alves, Pedro U.
AU - Catela, Bruno
AU - Soule, Bertrand
AU - Mateus, Tiago
AU - Mendes, Manuel João
AU - Águas, Hugo
AU - Fortunato, Elvira
AU - Martins, Rodrigo
N1 - A. Lyubchyk and A. Vicente contributed equally to this work. The work was supported by the Fundacao para a Ciencia e a Tecnologia (FCT) through the projects EXCL/CTM-NAN/0201/2012, UID/CTM/50025/2013, and PTDC/CTM-ENE/2514/2012; as well as by the European projects CEOPS (FP7 grant no 309984), i-Flexis (FP7-ICT grant no 611070), All-Oxide-Photovoltaics (FP7-FET grant no 309018). A. Vicente acknowledges support from FCT and MIT-Portugal, through the scholarship SFRH/BD/33978/2009. M. J. Mendes acknowledges funding by the EU Marie Curie Action FP7-PEOPLE-2013-IEF through the DIELECTRIC PV project (grant no 629370). Authors also acknowledge J. Pinto for carrying out the XRD measurements.
PY - 2016/9/1
Y1 - 2016/9/1
N2 - The post-deposition modification of ZnO-based transparent conductive oxides (TCOs) can be the key to produce thin films with optoelectronic properties similar to indium tin oxide (ITO), but at a much lower cost. Here, we present electro-optical results achieved for post-deposition annealing of Al–Zn–O (AZO), AZO:H, Ga–Zn–O:H (GZO:H), and Zn–O:H (ZNO:H) thin films deposited by RF sputtering at room temperature. These studies comprise results of thermal annealing at atmospheric pressure, vacuum, forming gas, H2 and Ar atmospheres, and H2 and Ar plasmas, which lead to significant enhancement of their electro-optical properties, which are correlated to morphological and structural improvements. The post-deposition annealing leads to an enhancement in resistivity above 40% for AZO, AZO:H, and GZO:H, reaching ρ ≈ 2.6–3.5 × 10−4 Ωcm, while ZnO:H showed a lower improvement of 13%. The averaged optical transmittance in the visible region is about 89% for the investigated TCOs. Such results match the properties of state-of-art ITO (ρ ≈ 10−4 Ωcm and transmittance in VIS range of 90%) employing much more earth-abundant materials.
AB - The post-deposition modification of ZnO-based transparent conductive oxides (TCOs) can be the key to produce thin films with optoelectronic properties similar to indium tin oxide (ITO), but at a much lower cost. Here, we present electro-optical results achieved for post-deposition annealing of Al–Zn–O (AZO), AZO:H, Ga–Zn–O:H (GZO:H), and Zn–O:H (ZNO:H) thin films deposited by RF sputtering at room temperature. These studies comprise results of thermal annealing at atmospheric pressure, vacuum, forming gas, H2 and Ar atmospheres, and H2 and Ar plasmas, which lead to significant enhancement of their electro-optical properties, which are correlated to morphological and structural improvements. The post-deposition annealing leads to an enhancement in resistivity above 40% for AZO, AZO:H, and GZO:H, reaching ρ ≈ 2.6–3.5 × 10−4 Ωcm, while ZnO:H showed a lower improvement of 13%. The averaged optical transmittance in the visible region is about 89% for the investigated TCOs. Such results match the properties of state-of-art ITO (ρ ≈ 10−4 Ωcm and transmittance in VIS range of 90%) employing much more earth-abundant materials.
KW - annealing
KW - hydrogenation
KW - thin films
KW - transparent conductive oxides
KW - ZnO
UR - http://www.scopus.com/inward/record.url?scp=84982994261&partnerID=8YFLogxK
U2 - 10.1002/pssa.201532891
DO - 10.1002/pssa.201532891
M3 - Article
AN - SCOPUS:84982994261
SN - 1862-6300
VL - 213
SP - 2317
EP - 2328
JO - Physica Status Solidi (A) Applications and Materials Science
JF - Physica Status Solidi (A) Applications and Materials Science
IS - 9
ER -