Ferroelectric and Ferromagnetic Properties and Magnetoelectric Coupling Effect of the Ba0.8Sr0.2TiO3/CoFe2O4 Heterostructure Film by Radio-Frequency Magnetron Sputtering

The Ba0.8Sr0.2TiO3/CoFe2O4layered heterostructure film was grown on Pt/TiO2/SiO2/Si substrate by radio frequency-magnetron sputtering. X-ray diffraction shows that the heterostructure film is composed of perovskite Ba0.8Sr0.2TiO3phase and spinel CoFe2O4phase. The microstructures of the heterostructure film were observed by field-emission scanning electron microscope (FESEM), showing good surface morphology and clear interfaces among the Ba0.8Sr0.2TiO3film and CoFe2O4film and substrate. The heterostructure film simultaneously diplays distinct ferroelectricity and ferromagnetism. Moreover, an obvious direct magnetoelectric coupling effect is observed in the heterostructure film with a maximum magnetoelectric voltage coefficient of 9.4 mV/cm Oe.

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Effects of Thermal Annealing on the Properties of Zirconium-Doped MgxZn1−XO Films Obtained through Radio-Frequency Magnetron Sputtering

Membranes ◽

10.3390/membranes11050373 ◽

2021 ◽

Vol 11 (5) ◽

pp. 373

Author(s):

Wen-Yen Lin ◽

Feng-Tsun Chien ◽

Hsien-Chin Chiu ◽

Jinn-Kong Sheu ◽

Kuang-Po Hsueh

Keyword(s):

Magnetron Sputtering ◽

Radio Frequency ◽

Photoelectron Spectroscopy ◽

Annealing Temperature ◽

Radio Frequency Magnetron ◽

Radio Frequency Magnetron Sputtering ◽

X Ray Diffraction ◽

Free Electrons ◽

X Ray ◽

Mg Content

Zirconium-doped MgxZn1−xO (Zr-doped MZO) mixed-oxide films were investigated, and the temperature sensitivity of their electric and optical properties was characterized. Zr-doped MZO films were deposited through radio-frequency magnetron sputtering using a 4-inch ZnO/MgO/ZrO2 (75/20/5 wt%) target. Hall measurement, X-ray diffraction (XRD), transmittance, and X-ray photoelectron spectroscopy (XPS) data were obtained. The lowest sheet resistance, highest mobility, and highest concentration were 1.30 × 103 Ω/sq, 4.46 cm2/Vs, and 7.28 × 1019 cm−3, respectively. The XRD spectra of the as-grown and annealed Zr-doped MZO films contained MgxZn1−xO(002) and ZrO2(200) coupled with Mg(OH)2(101) at 34.49°, 34.88°, and 38.017°, respectively. The intensity of the XRD peak near 34.88° decreased with temperature because the films that segregated Zr4+ from ZrO2(200) increased. The absorption edges of the films were at approximately 348 nm under 80% transmittance because of the Mg content. XPS revealed that the amount of Zr4+ increased with the annealing temperature. Zr is a potentially promising double donor, providing up to two extra free electrons per ion when used in place of Zn2+.

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Study of the Capacitive Properties of Strontium Barium Niobate Deposited by Radio Frequency Magnetron Sputtering

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.941-944.1306 ◽

2014 ◽

Vol 941-944 ◽

pp. 1306-1310

Author(s):

Sheng Chien Su ◽

Wen Chung Chang ◽

Chia Ching Wu

Keyword(s):

Thin Films ◽

Magnetron Sputtering ◽

Radio Frequency ◽

Amorphous Structure ◽

Radio Frequency Magnetron ◽

Radio Frequency Magnetron Sputtering ◽

X Ray Diffraction ◽

X Ray ◽

Capacitive Properties ◽

Capacitance Voltage

Ferroelectric SrxBa1−xNb2O6 (SBN) thin films are deposited on Al/Si (100) substrates by radio frequency magnetron sputtering at room temperature. The nanograin sizes of the SBN thin films were analized by scanning electron microscopy (SEM). X-ray diffraction reveals that all the SBN thin films show an amorphous structure because they were deposited at room temperature.The capacitive properties of the SBN thin films were measured using metal ferroelectric insulation semiconductor (MFIS) structures. The memory window of the MFIS structure was characterized with a capacitance-voltage (C-V) method.

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Thermal stability of post-growth-annealed Ga-doped MgZnO films grown by the RF sputtering method

MRS Proceedings ◽

10.1557/opl.2014.836 ◽

2014 ◽

Vol 1675 ◽

pp. 41-44

Author(s):

Kuang-Po Hsueh ◽

Po-Wei Cheng ◽

Wen-Yen Lin ◽

Hsien-Chin Chiu ◽

Hsiang-Chun Wang ◽

...

Keyword(s):

Magnetron Sputtering ◽

Radio Frequency ◽

Thermal Annealing ◽

Rf Sputtering ◽

Radio Frequency Magnetron ◽

Radio Frequency Magnetron Sputtering ◽

X Ray Diffraction ◽

Light Emitting ◽

Near Ultraviolet ◽

Transparent Contact

ABSTRACTA radio-frequency magnetron sputtering technique and subsequent rapid thermal annealing (RTA) at 600, 700, 800, and 900 °C were implemented to grow high-quality Ga-doped MgxZn1-xO (GMZO) epi-layers. The GMZO films were deposited using a radio-frequency magnetron sputtering system and a 4 inch ZnO/MgO/Ga2O3 (75/20/5 wt %) target. The Hall results, X-ray diffraction (XRD), and transmittance were determined and are reported in this paper. The Hall results indicated that the increase in mobility was likely caused by the improved crystallization in the GMZO films after thermal annealing. The XRD results revealed that MgxZn1-xO (111) and MgO2 (200) peaks were obtained in the GMZO films. The absorption edges of the as-grown and annealed GMZO films shifted toward the short wavelength of 373 nm at a transmittance of 90%. According to these results, GMZO films are feasible for forming transparent contact layers for near-ultraviolet light-emitting diodes.

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Structural and Optical Changes of Undoped GaN Layers Grown via Radio-frequency Magnetron Sputtering Obtained from GaN Powders

European Journal of Engineering Research and Science ◽

10.24018/ejers.2019.4.2.1164 ◽

2019 ◽

Vol 4 (2) ◽

pp. 59-63

Author(s):

Erick Gastellóu ◽

Crisoforo Morales ◽

Godofredo García ◽

Rafael García ◽

Gustavo Alonso Hirata ◽

...

Keyword(s):

Magnetron Sputtering ◽

Radio Frequency ◽

Crystal Size ◽

Radio Frequency Magnetron ◽

Radio Frequency Magnetron Sputtering ◽

X Ray Diffraction ◽

Homogeneous Surface ◽

X Ray ◽

Significant Difference ◽

Diffraction Patterns

Undoped GaN layers were grown via radio-frequency magnetron sputtering, using a target manufactured with undoped GaN powders. Where the GaN powders were sintetized by nitridation of metallic gallium at 1000 °C in ammonia flow for two hours. X-ray diffraction patterns demonstrated that there are not a significant difference between the diffraction angles of the GaN powders and the GaN layers. The x-ray diffraction patterns for the GaN powders showed narrow peaks with a crystal size of 41 nm, while the GaN layers showed broad peaks with a crystal size of 7.7 nm. Scanning electron microscopy micrographs demonstrated the formation of crystals of irregular size with an average length of 1.56 μm for the GaN powders, while a homogeneous surface morphology with a thickness of 6.6 μm for the GaN layers was observed. Photoluminescence spectra showed a high emission at 3.49 eV (355.13 nm) for the GaN powders and an emission band energy located at 3.42 eV (361.54 nm) for the GaN layers, both emission bands were related to the band-to-band transition for the GaN. Raman spectra for the GaN powders showed the A1(TO), E1(TO), and E2(High) classical vibration modes. The GaN layers only showed the A1(TO) mode.

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