Nanoscale potential fluctuations in nonstoichiometrics tantalum oxide

Gritsenko, V. A.; Володин, В. А.; Перевалов, Т. В.; Кручинин, В. Н.; Gerasimova, A. K.; Алиев, В. Ш.; Prosvirin, Igor P.

doi:10.1088/1361-6528/aad430

Cited by 9 publications

(4 citation statements)

References 31 publications

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“…This feature can be modeled using a broad Lorentz function. Sub-gap absorption has been observed previously in sub-stoichiometric TaO x films [42], and was associated with the presence of V O s [43][44][45]. From figure 1(e), it can be seen that the optical responses of both TaO x and Zr:TaO x exhibit considerable sub-gap absorption, thus confirming the XPS results.…”

Section: Resultssupporting

confidence: 87%

Oxygen vacancy engineering of TaO _x -based resistive memories by Zr doping for improved variability and synaptic behavior

et al. 2021

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Resistive switching (RS) devices are promising forms of non-volatile memory. However, one of the biggest challenges for RS memory applications is the device-to-device (D2D) variability, which is related to the intrinsic stochastic formation and configuration of oxygen vacancy (VO) conductive filaments (CFs). In order to reduce the D2D variability, control over the formation and configuration of oxygen vacancies is paramount. In this study, we report on the Zr doping of TaO x -based RS devices prepared by pulsed-laser deposition as an efficient means of reducing the VO formation energy and increasing the confinement of CFs, thus reducing D2D variability. Our findings were supported by XPS, spectroscopic ellipsometry and electronic transport analysis. Zr-doped films showed increased VO concentration and more localized VOs, due to the interaction with Zr. DC and pulse mode electrical characterization showed that the D2D variability was decreased by a factor of seven, the resistance window was doubled, and a more gradual and monotonic long-term potentiation/depression in pulse switching was achieved in forming-free Zr:TaO x devices, thus displaying promising performance for artificial synapse applications.

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Section: Resultssupporting

confidence: 87%

Oxygen vacancy engineering of TaO _x -based resistive memories by Zr doping for improved variability and synaptic behavior

et al. 2021

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“…al [19] similarly observed a Ce-rich layer in Ce-doped ZnO thin lms, while Wang and co-workers [20] declared the peaks to ne ZnO powder to acoustic overtone by A 1 symmetry. Moreover, the peaks at 801 and 920 cm − 1 are representations of the two optical phonon (2LO) mode of amorphous tantalum oxide and asymmetric stretching of Si and oxygen bonds, respectively [21]. The nal peak at 1109 cm − 1 is attributed to the symmetry acoustic combination of A 1 and E 2 modes of Raman bands [22,23].…”

Section: Resultsmentioning

confidence: 99%

Studies on the surface and optical properties of Ta-doped ZnO thin films deposited by thermionic vacuum arc

et al. 2021

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In this research, Ta doped ZnO thin lms have been deposited onto glass and Si substrate by Thermionic vacuum arc (TVA) thin lm deposition system. TVA is anodic plasma thin lm deposition system and it is used to relatively high-quality thin lms deposition. ZnO thin lms have direct optical band gap of 3.37 eV. Tantalum is an e cient higher-valance element. Ta atom gives the more electrons compared to Zinc atom and their ionic radius are very close to each other, so substituted element does not bring into additional stress in crystal network. The deposited thin lms were analyzed by eld emission scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy, atomic force microscopy, UV-Vis spectrophotometry and interferometer. To change the band gap properties of the ZnO thin lm, Ta doping was used and band gap of Ta doped ZnO thin lm was obtained 3.1 eV by Tauc's method. The wt % ratios for Zn/Ta were calculated as 0.45 and 0.42 for the lms deposited onto glass and Si substrate, respectively. Crystallite sizes of Ta doped ZnO thin lm was decreased by changing substrate material.To the best of our knowledge, substituted Ta elements connected to the oxygen atom in crystal network and orthorhombic β′-Ta 2 O 5 were detected in the all lms structure. Their band gaps of the β′-Ta 2 O 5 were measured as 2.70 eV and 2.60 eV for Ta-doped ZnO thin lms deposited onto glass and Si substrate, respectively. Up to day, the band gap of the β′-Ta 2 O 5 was calculated by density function theory. According to results, β′-Ta 2 O 5 structure was found as embedded from in the ZnO crystal network.

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Section: Resultsmentioning

confidence: 99%

Studies on the Surface and Optical Properties of Ta-Doped ZnO Thin Films Deposited By Thermionic Vacuum Arc

Pat

Mohammadigharehbagh

Akkurt

et al. 2021

Preprint

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In this research, Ta doped ZnO thin films have been deposited onto glass and Si substrate by Thermionic vacuum arc (TVA) thin film deposition system. TVA is anodic plasma thin film deposition system and it is used to relatively high-quality thin films deposition. ZnO thin films have direct optical band gap of 3.37 eV. Tantalum is an efficient higher-valance element. Ta atom gives the more electrons compared to Zinc atom and their ionic radius are very close to each other, so substituted element does not bring into additional stress in crystal network. The deposited thin films were analyzed by field emission scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy, atomic force microscopy, UV-Vis spectrophotometry and interferometer. To change the band gap properties of the ZnO thin film, Ta doping was used and band gap of Ta doped ZnO thin film was obtained 3.1 eV by Tauc’s method. The wt % ratios for Zn/Ta were calculated as 0.45 and 0.42 for the films deposited onto glass and Si substrate, respectively. Crystallite sizes of Ta doped ZnO thin film was decreased by changing substrate material. To the best of our knowledge, substituted Ta elements connected to the oxygen atom in crystal network and orthorhombic β′-Ta2O5 were detected in the all films structure. Their band gaps of the β′-Ta2O5 were measured as 2.70 eV and 2.60 eV for Ta-doped ZnO thin films deposited onto glass and Si substrate, respectively. Up to day, the band gap of the β′-Ta2O5 was calculated by density function theory. According to results, β′-Ta2O5 structure was found as embedded from in the ZnO crystal network.

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Nanoscale potential fluctuations in nonstoichiometrics tantalum oxide

Cited by 9 publications

References 31 publications

Oxygen vacancy engineering of TaO _x -based resistive memories by Zr doping for improved variability and synaptic behavior

Oxygen vacancy engineering of TaO _x -based resistive memories by Zr doping for improved variability and synaptic behavior

Studies on the surface and optical properties of Ta-doped ZnO thin films deposited by thermionic vacuum arc

Studies on the Surface and Optical Properties of Ta-Doped ZnO Thin Films Deposited By Thermionic Vacuum Arc

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Nanoscale potential fluctuations in nonstoichiometrics tantalum oxide

Cited by 9 publications

References 31 publications

Oxygen vacancy engineering of TaO x -based resistive memories by Zr doping for improved variability and synaptic behavior

Oxygen vacancy engineering of TaO x -based resistive memories by Zr doping for improved variability and synaptic behavior

Studies on the surface and optical properties of Ta-doped ZnO thin films deposited by thermionic vacuum arc

Studies on the Surface and Optical Properties of Ta-Doped ZnO Thin Films Deposited By Thermionic Vacuum Arc

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Oxygen vacancy engineering of TaO _x -based resistive memories by Zr doping for improved variability and synaptic behavior

Oxygen vacancy engineering of TaO _x -based resistive memories by Zr doping for improved variability and synaptic behavior