Epitaxial highly ordered Sb:SnO2 nanowires grown by the vapor liquid solid mechanism on m-, r- and a-Al2O3. Issue 5 (15th April 2019)

• Record Type: Journal Article
• Authors: Zervos, M.; Lathiotakis, N.; Kelaidis, N.; Othonos, A.; Tanasa, E.; Vasile, E.
• Is Part Of: Nanoscale advances. Volume 1:Issue 5(2019)
• Page Start: 1980
• Page End: 1990
• Publication Date: 2019-04-15
• Subjects: 620.5
• DOI: 10.1039/c9na00074g
• Languages: English
• ISSNs: 2516-0230

Abstract

Abstract : Epitaxial, highly ordered Sb:SnO2 nanowires were grown by the vapor–liquid–solid mechanism on m-, r- and a-Al2 O3 between 700 °C and 1000 °C using metallic Sn and Sb with a mass ratio of Sn/Sb = 0.15 ± 0.05 under a flow of Ar and O2 at 1 ± 0.5 mbar. Abstract : Epitaxial, highly ordered Sb:SnO2 nanowires were grown by the vapor–liquid–solid mechanism on m-, r- and a-Al2 O3 between 700 °C and 1000 °C using metallic Sn and Sb with a mass ratio of Sn/Sb = 0.15 ± 0.05 under a flow of Ar and O2 at 1 ± 0.5 mbar. We find that effective doping and ordering can only be achieved inside this narrow window of growth conditions. The Sb:SnO2 nanowires have the tetragonal rutile crystal structure and are inclined along two mutually perpendicular directions forming a rectangular mesh on m-Al2 O3 while those on r-Al2 O3 are oriented in one direction. The growth directions do not change by varying the growth temperature between 700 °C and 1000 °C but the carrier density decreased from 8 × 10 19 cm −3 to 4 × 10 17 cm −3 due to the re-evaporation and limited incorporation of Sb donor impurities in SnO2 . The Sb:SnO2 nanowires on r-Al2 O3 had an optical transmission of 80% above 800 nm and displayed very long photoluminescence lifetimes of 0.2 ms at 300 K. We show that selective area location growth of highly ordered Sb:SnO2 nanowires is possible by patterning the catalyst which is important for the realization of novel nanoscale devices such as nanowire solar cells.