Magnetotransport Properties of MnGeAs2 Films

MnGeAs2 thin films were successfully deposited on GaAs(100) substrate. The films exhibited room-temperature ferromagnetism with TC ~ 330 K, based on both magnetization and resistance measurements at temperatures from 5 to 370 K. The coercive fields at 5 and 300 K were 2100 and 50 Oe. The anomalous Hall effect was observed, suggesting the existence of spin polarized carriers in MnGeAs2 thin films. The magnetoresistance (MR) measurements showed very small change (~ 0.1% at 5 K) in resistance at low temperature. The MR value at 5 K was smaller than that (~ 9% at 305 K) at room temperature (305 K). Type of majority carriers in the films was determined to be n-type by Hall measurement above the transition temperature. The effective carrier density was 1.8´1020 cm-3. The diode current-voltage characteristics were shown in a hetero-junction MnGeAs2 film on a conducting p-type GaAs substrate.

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Photosensitive Amorphous Si Thin Films Prepared by Magnetron Technology.

MRS Proceedings ◽

10.1557/proc-744-m5.20 ◽

2002 ◽

Vol 744 ◽

Author(s):

Galina Khlyap ◽

Victor Brytan

Keyword(s):

Thin Films ◽

Room Temperature ◽

Continuous Mode ◽

Applied Bias ◽

Near Ir ◽

Current Voltage ◽

Exponential Character ◽

Current Voltage Characteristics ◽

Amorphous Si ◽

Spectral Ranges

ABSTRACTElectric field – induced effects are studied in thin films of amorphous Si grown by magnetron sputtering performed in continuous and pulse modes. Current-voltage characteristics are measured under the room temperature in different spectral ranges. It is shown that the investigated dependencies are of exponential character in all range of applied bias. Good photosensitivity was revealed by the samples prepared in continuous mode in the near-IR and visible interval. The samples grown by the pulse magnetron technology were shown room-temperature photosensitivity in near-IR range after 2000C hydrogenation.

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Optical and Electrical Properties of Some Organic Thin Films for Optoelectronic Applications

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.337.426 ◽

2011 ◽

Vol 337 ◽

pp. 426-429

Author(s):

S.B. Chen ◽

Zhi You Zhong

Keyword(s):

Thin Films ◽

Experimental Studies ◽

Visible Region ◽

Organic Thin Films ◽

Optical Transmittance ◽

Vacuum Sublimation ◽

Semiconductor Thin Films ◽

Current Voltage ◽

Current Voltage Characteristics ◽

Effective Carrier

Organic semiconductor thin films of bis-(2-methyl-8-quinolinolato)-4-(phenyl-phenolato) -aluminium-(III) (BAlq), N,N′-bis(naphthalen-1-yl)-N,N′-bis(phenyl)benzidine (NPB), and tris-(8- hydroxyquinoline) aluminum (Alq) were prepared by the vacuum sublimation technique. The optical properties in the UV-visible region of the thin films were investigated by optical transmittance and absorbance spectra. The optical energy gaps were obtained from direct allowed transitions at room temperature by Tauc’s law. The Urbach energy and the slope of Urbach edge were estimated by the Urbach-edges method, respectively. Furthermore, the current-voltage characteristics of organic thin films were analyzed, and the different slopes in the lower and higher voltage regions were observed. From the experimental studies, the effective carrier mobility, free carrier density, and electrical conductivity were also evaluated respectively.

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The Properties of n-ZnO/p-SiC Heterojunctions and their Potential Applications for Devices

Materials Science Forum ◽

10.4028/www.scientific.net/msf.527-529.1571 ◽

2006 ◽

Vol 527-529 ◽

pp. 1571-1574 ◽

Cited By ~ 1

Author(s):

Cole W. Litton ◽

Ya.I. Alivov ◽

D. Johnstone ◽

Ümit Özgür ◽

V. Avrutin ◽

...

Keyword(s):

Room Temperature ◽

Molecular Beam ◽

Reverse Bias ◽

Zno Films ◽

Turn On ◽

Forward Current ◽

Current Voltage ◽

Potential Applications ◽

Current Voltage Characteristics ◽

P Type

Heteroepitaxial n-ZnO films have been grown on commercial p-type 6H-SiC substrates by plasma-assisted molecular-beam epitaxy, and n-ZnO/p-SiC heterojunction mesa structures have been fabricated and their photoresponse properties have been studied. Current-voltage characteristics of the structures had a very good rectifying diode-like behavior with a leakage current less than 2 x 10-4 A/cm2 at -10 V, a breakdown voltage greater than 20 V, a forward turn on voltage of ∼5 V, and a forward current of ∼2 A/cm2 at 8 V. Photosensitivity of the diodes, when illuminated from ZnO side, was studied at room temperature and photoresponsivity of as high as 0.045 A/W at -7.5 V reverse bias was observed for photon energies higher than 3.0 eV.

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Anomalous Magneto-Electric Properties in Chalcopyrite MnGeP2 Films

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.864.111 ◽

2017 ◽

Vol 864 ◽

pp. 111-115

Author(s):

Yun Ki Kim ◽

J.B. Ketterson

Keyword(s):

Thin Films ◽

Room Temperature ◽

Anomalous Hall Effect ◽

Alloy Film ◽

Ferromagnetic Transition ◽

Field Sweep ◽

Maximum Change ◽

Hall Effects ◽

Spin Polarized ◽

Field Dependent

We have successfully grown MnGeP2 thin films and Ge and MnGeP2 alloy films on GaAs(100) substrate. Magnetization measurements have been performed on MnGeP2 film samples at temperatures from 5 to 400 K. The measurements have shown that there are a ferromagnetic to paramagnetic transition above room temperature. Field dependent magnetization experiments have shown a coercive field of 160, 1400, 3900 Oe at 300, 250 and 5 K, respectively. A negative magnetoresistance (MR) has been found with a maximum change less than 2% at 5 T and 5 K. The MR measurements on the films have displayed hysteric behaviors with respect to the external field sweep at low fields at temperature below the ferromagnetic transition. Anomalous Hall effects have been found in the MnGeP2 film and Ge and MnGeP2 alloy film samples. Above the transition temperature neither hysteric behavior nor anomalous Hall effect was found. These results imply that spin polarized hole carriers exist in the MnGeP2 films.

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Room-temperature ferromagnetism in p-type (Mn, N)-codoped ZnO thin films achieved by thermal oxidation of sputtered Zn3N2:Mn films

Journal of Physics D Applied Physics ◽

10.1088/0022-3727/41/11/115008 ◽

2008 ◽

Vol 41 (11) ◽

pp. 115008 ◽

Cited By ~ 5

Author(s):

Z L Lu ◽

Z R Mo ◽

W Q Zou ◽

S Wang ◽

G Q Yan ◽

...

Keyword(s):

Thin Films ◽

Thermal Oxidation ◽

Room Temperature ◽

Room Temperature Ferromagnetism ◽

Zno Thin Films ◽

P Type

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Ga1-xGdxN-Based Spin Polarized Light Emitting Diode

MRS Proceedings ◽

10.1557/opl.2011.584 ◽

2011 ◽

Vol 1290 ◽

Author(s):

Muhammad Jamil ◽

Tahir Zaidi ◽

Andrew Melton ◽

Tianming Xu ◽

Ian T. Ferguson

Keyword(s):

Room Temperature ◽

Light Emitting Diode ◽

Room Temperature Ferromagnetism ◽

Polarized Light ◽

Type Material ◽

Degree Of Polarization ◽

Co Doping ◽

Spin Polarized ◽

P Type ◽

Co Doped

ABSTRACTIn this work, a room temperature spin-polarized LED based on ferromagnetic Ga1-xGdxN is reported. The device was grown by metalorganic chemical vapor deposition (MOCVD) and is the first report of a spin-LED based on Ga1-xGdxN. Electroluminescence from this device had a degree of polarization of 14.6% at 5000 Gauss and retained a degree of polarization of 9.3% after removal of the applied magnetic field. Ga1-xGdxN thin films were grown on 2 μm GaN templates and were co-doped with Si and Mg to achieve n-type and p-type materials. Co-doping of the Ga1-xGdxN films with Si produced conductive n-type material, while co-doping with Mg produced compensated p-type material. Both Si and Mg co-doped films exhibited room temperature ferromagnetism, measured by vibrating sample magnetometry.

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ROOM TEMPERATURE FERROMAGNETISM IN (N, Co)-CODOPED ZnO THIN FILMS

Modern Physics Letters B ◽

10.1142/s0217984907013195 ◽

2007 ◽

Vol 21 (13) ◽

pp. 799-806 ◽

Cited By ~ 3

Author(s):

D. L. HOU ◽

X. J. YE ◽

H. J. MENG ◽

X. Y. ZHAO ◽

H. J. ZHOU ◽

...

Keyword(s):

Thin Films ◽

Room Temperature ◽

Room Temperature Ferromagnetism ◽

Inverse Correlation ◽

Zno Thin Films ◽

Clear Correlation ◽

Ferromagnetic Property ◽

Glass Substrates ◽

P Type ◽

Co Doped

A series of nitrogen-doped Zn 0.93 Co 0.07 O thin films grown on glass substrates were prepared by magnetron sputtering, which have shown ferromagnetic property at room temperature. The largest moment of about 4.92 μB/ Co and Curie temperature (T c ) of about 300 K were observed for Zn 0.93 Co 0.07 O thin film. P-type Co -doped ZnO thin films with room temperature ferromagnetism were obtained. We demonstrated a clear correlation between nitrogen and transition temperature and an inverse correlation between nitrogen and magnetization per Co ion.

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Oxygen vacancy mediated room temperature ferromagnetism in Cu-doped LiNbO3 thin films

Journal of Magnetism and Magnetic Materials ◽

10.1016/j.jmmm.2021.167775 ◽

2021 ◽

Vol 527 ◽

pp. 167775

Author(s):

Xiaodong Zhou ◽

Erlei Wang ◽

Xiaodong Lao ◽

Yongmei Wang ◽

Honglei Yuan

Keyword(s):

Thin Films ◽

Oxygen Vacancy ◽

Room Temperature ◽

Room Temperature Ferromagnetism

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Preparation and Electrical Characteristics of (100), (111), and Randomly Oriented PZT Thin Films

MRS Proceedings ◽

10.1557/proc-361-445 ◽

1994 ◽

Vol 361 ◽

Author(s):

Chang Jung Kim ◽

Dae Sung Yoon ◽

Joon Sung Lee ◽

Chaun Gi Choi ◽

Won Jong Lee ◽

...

Keyword(s):

Thin Films ◽

Sol Gel ◽

Hysteresis Loops ◽

Test System ◽

Electrical Characteristics ◽

Pzt Thin Films ◽

Pole Figures ◽

Current Voltage ◽

Current Voltage Characteristics ◽

Drying Conditions

ABSTRACTThe (100), (111) and randomly oriented PZT thin films were fabricated on Pt/Ti/Coming 7059 glass using sol-gel method. The thin films having different orientation were fabricated by different drying conditions for pyrolysis. The preferred orientations of the PZT thin films were observed using XRD, rocking curves, and pole figures. The microstructures were investigated using SEM. The hysteresis loops and capacitance-voltage characteristics of the films were investigated using a standardized ferroelectric test system. The dielectric constant and current-voltage characteristics of the films were investigated using an impedance analyzer and pA meter, respectively. The films oriented in a particular direction showed superior electrical characteristics to the randomly oriented films.

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