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The relationship between the sheet carrier concentration, ns, of LaCrO3(LCO)/SrTiO3(STO) heterostructures and their structural properties has been investigated. Under low oxygen partial pressure, the STO substrate is reduced during growth as evidenced by a high ns of 1016 cm−2. By controlling the post-growth annealing conditions, heterostructures with ns of 1013–1016 cm−2 are achieved. The atomic-scale structure of the samples is obtained using high-resolution synchrotron x-ray diffraction measurements. For heterostructures with ns at or below 3 × 1013 cm−2, polar distortions are present within the LCO layers and increase in magnitude with a decrease in sheet carrier concentration. These distortions are absent for samples with ns on the order of 1015–1016 cm−2 where interfacial carriers play a role in alleviating the polar discontinuity at the LCO/STO interface. These results suggest that interfacial charge carriers and polar distortions can act as complementary mechanisms to alleviate the polar discontinuity at polar/non-polar complex oxide interfaces.
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Electrical properties and interface abruptness of AlSiO gate dielectric grown on 000 1 ¯ N-polar and (0001) Ga-polar GaN
- Award ID(s):
- 1839077
- PAR ID:
- 10191610
- Date Published:
- Journal Name:
- Applied Physics Letters
- Volume:
- 115
- Issue:
- 17
- ISSN:
- 0003-6951
- Page Range / eLocation ID:
- 172104
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1063/1.5125788
