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Crystallization of TiO2 polymorphs from RF-sputtered, amorphous thin-film precursors

Journal Article · · AIP Advances
DOI:https://doi.org/10.1063/1.5140368· OSTI ID:1602697
Crystalline TiO2 films of anatase, brookite, and rutile are reproducibly made from amorphous precursors deposited by RF magnetron sputtering, producing large-area, single phase films of uniform thickness. Sputtered amorphous TiO2 precursor thin films follow the general behavior observed for amorphous precursor thin films generated by pulsed laser deposition, namely, that oxygen deficiency is necessary for the formation of brookite and rutile. We quantify the oxygen deficiency and correlate it with the long wavelength optical absorption. We find that the precursor deposition rate is also a contributing factor to phase selection and that brookite and rutile form from films deposited more rapidly and anatase from films deposited more slowly. Sputtered and pulsed laser deposited amorphous precursor films prepared with similar oxygen deficiency and similar thickness result in the same final state after annealing, but the rate for sputtered precursors is slower.
Research Organization:
National Renewable Energy Laboratory (NREL), Golden, CO (United States); SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)
Sponsoring Organization:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
Grant/Contract Number:
AC02-76SF00515; AC36-08GO28308
OSTI ID:
1602697
Alternate ID(s):
OSTI ID: 1633974
OSTI ID: 1598071
Report Number(s):
NREL-JA--5K00-76206
Journal Information:
AIP Advances, Journal Name: AIP Advances Journal Issue: 2 Vol. 10; ISSN 2158-3226
Publisher:
American Institute of Physics (AIP)Copyright Statement
Country of Publication:
United States
Language:
English

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