Growth of high-quality STO(111)/Pt(111) thin films on r-Al2O3 substrate by RF magnetron sputter deposition
ORAL
Abstract
SrTiO3 (STO) thin films (20-30nm) with high-quality crystal structure and low roughness can be used as growth templates for complex oxides or as the dielectric materials for capacitor structures.
In this work, stoichiometric STO thin films were grown by radio frequency (RF) magnetron sputtering on Pt(111) templates grown on r-Al2O3 substrates, and the effects of growth parameters as well as the underlying Pt template’s structural properties on the quality of STO films were studied. This Pt template can also be used as a bottom electrode for capacitor structures.
The 50 nm thick Pt thin films were deposited at 600℃ and 90W power. The STO films were then grown at 300℃ at powers ranging from 20W to 40W, followed by annealing at 550℃ for 1 hour. The thickness of these STO films ranged from 30nm +/- 5 nm (20W) to 60nm +/- 5 nm (40W), as measured by profilometry. The structural properties of these STO/Pt films were characterized via X-ray diffraction (XRD), atomic force microscopy (AFM), and reflection high-energy electron diffraction (RHEED).
The XRD results reveal strongly oriented (111) STO and Pt (111) thin films, streaky RHEED patterns indicate 2D growth, and AFM shows a roughness less than 1nm.
These results highlight the potential for STO thin films to be used as a platform for oxide growth or for high-temperature (up to 600℃) capacitor applications with further investigation of electric properties of films.
In this work, stoichiometric STO thin films were grown by radio frequency (RF) magnetron sputtering on Pt(111) templates grown on r-Al2O3 substrates, and the effects of growth parameters as well as the underlying Pt template’s structural properties on the quality of STO films were studied. This Pt template can also be used as a bottom electrode for capacitor structures.
The 50 nm thick Pt thin films were deposited at 600℃ and 90W power. The STO films were then grown at 300℃ at powers ranging from 20W to 40W, followed by annealing at 550℃ for 1 hour. The thickness of these STO films ranged from 30nm +/- 5 nm (20W) to 60nm +/- 5 nm (40W), as measured by profilometry. The structural properties of these STO/Pt films were characterized via X-ray diffraction (XRD), atomic force microscopy (AFM), and reflection high-energy electron diffraction (RHEED).
The XRD results reveal strongly oriented (111) STO and Pt (111) thin films, streaky RHEED patterns indicate 2D growth, and AFM shows a roughness less than 1nm.
These results highlight the potential for STO thin films to be used as a platform for oxide growth or for high-temperature (up to 600℃) capacitor applications with further investigation of electric properties of films.
*This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences Established Program to Stimulate Competitive Research (EPSCoR) under Award Number DE-SC0021981.
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Presenters
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Ekaterina Taylor
- University of Maine