Enhancement of electrical properties of Al-doped ZnO thin films (AZO) by hydrogene plasma treatment

Transparent and conductive Al-doped ZnO (AZO) films were prepared by magnetron sputtering at temperature 200oC onto glass substrate. The films were treated with hydrogen plasma at temperatures 200oC from 30 to 60 minutes with 200 mW/cm2 power plasma. The optical, electrical and structural characteristics of the AZO coatings were analyzed as a function of the treatment time by spectrophotometry,Hall effects measurements, and X-ray diffraction. Results of X-ray diffraction analysis showed that the structure of the plasma-treated film did not change compared to that of the asdeposited film. The electrical resistivity of the AZO films decreased after H2 plasma treatment. The plasma treatment not only significantly decreased film resistivity but enhanced electrical stability as aging in air ambient. The average optical transmittance in the wave length range of 300 to 700 nm was 85%. These results were significant in application of AZO thin film as transparent electrode for a-Si:H based thin film solar cell prepared by PE-CVD method in next step.

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Formation of ZnO Doped with Mn Thin Film by Electrodeposition and Magnetic Behaviour.

MRS Proceedings ◽

10.1557/proc-879-z7.17 ◽

2005 ◽

Vol 879 ◽

Author(s):

M. Abid ◽

C. Terrier ◽

J-P Ansermet ◽

K. Hjort

Keyword(s):

Thin Film ◽

Thin Films ◽

Room Temperature ◽

Magnetic Behaviour ◽

Spectroscopic Methods ◽

X Ray Diffraction ◽

X Ray ◽

Doped Zno ◽

Mn Doped ◽

Weak Ferromagnetic

AbstractFollowing the theory, ferromagnetism is predicted in Mn- doped ZnO, Indeed, ferromagnetism above room temperature was recently reported in thin films as well as in bulk samples made of this material. Here, we have prepared Mn doped ZnO by electrodeposition. The samples have been characterized by X-ray diffraction and spectroscopic methods to ensure that the dopants are substitutional. Some samples exhibit weak ferromagnetic properties at room temperature, however to be useful for spintronics this material need additional carriers provided by others means.

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Development of Top-Gate Nanocrystalline Si:H Thin Film Transistors

MRS Proceedings ◽

10.1557/proc-808-a9.37 ◽

2004 ◽

Vol 808 ◽

Author(s):

Jarrod McDonald ◽

Vikram L. Dalal ◽

Max Noack

Keyword(s):

Thin Film ◽

Thin Film Transistors ◽

Breakdown Strength ◽

Defect Density ◽

Hydrogen Plasma ◽

Interface State ◽

Nitride Layer ◽

High Ratio ◽

X Ray Diffraction ◽

X Ray

ABSTRACTWe report on the growth and fabrication of top gate thin film transistors at low temperatures in nanocrystalline Si:H. The nanocrystalline Si:H was deposited using a VHF-PECVD plasma process at 45 MHz in a diode reactor. The material was deposited from a mixture of silane and hydrogen at a temperature of 250-300°C. Higher temperatures resulted in a loss of hydrogen from the material. The properties of the nanocrystalline Si:H were studied using x-ray diffraction and Raman spectroscopy. The material showed a high ratio (3.8) between the crystalline and amorphous peaks in the Raman spectrum. X-ray diffraction data showed the films to be predominantly oriented in <111> direction, and the grain size estimated from Scherer's formula was in the range of 12-15 nm. The doping of the material could be changed by introducing ppm levels of Boron or Phosphorus. The as-grown material was generally n type. By adding controlled amounts of B, the material could be made p type. The devices made were n-channel MISFET's with p body. The n+ source and drain layers were made from amorphous Si:H. A systematic investigation of the appropriate oxide/nitride layer to be used was undertaken. The nitride layers were grown at 250-300°C using mixtures of silane and ammonia, with a high degree of dilution by helium. The presence of helium dilution, along with post-deposition passivation by a hydrogen plasma, was found to produce reproducible, low interface defect density nitride materials. Interface state densities were measured using capacitance spectroscopy at different frequencies and temperatures and found to be in the range of 4.5x1011/cm2-eV. The breakdown strength of the nitride was measured and found to be 4 MV/cm. Proof-of-concept TFT devices were fabricated using reactive ion etching. The threshold voltage was in the range of 13-15 V, and the on/off ratio was in the range of 103.

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The Structural Characteristics of CIS Thin Films Prepared by Electro-Deposited Method

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.818.88 ◽

2013 ◽

Vol 818 ◽

pp. 88-91

Author(s):

Kun Liu ◽

Ji Sheng Yang ◽

Rui Li ◽

Wei Peng ◽

Shi Pan

Keyword(s):

Thin Film ◽

Thin Films ◽

Raman Spectroscopy ◽

Raman Spectrum ◽

Structural Characteristics ◽

X Ray Diffraction ◽

Electro Deposition ◽

X Ray ◽

Micro Raman Spectroscopy ◽

Deposition Technology

The properties of the absorber layer of solar cell CuInSe2(CIS) thin film made by electro-depostied method were researched in this article. Different concentration of reactant and voltage was applied to prepare the CIS film. The micro-Raman spectroscopy and X-ray diffraction (XRD) of CIS film was carried out. A correlation between the linewidth A1 mode of Raman spectrum and the XRD line and the voltage of electro-deposition technology was found.

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Modified statistical dynamical diffraction theory: analysis of model SiGe heterostructures

Journal of Applied Crystallography ◽

10.1107/s0021889813011308 ◽

2013 ◽

Vol 46 (4) ◽

pp. 912-918

Author(s):

P. K. Shreeman ◽

K. A. Dunn ◽

S. W. Novak ◽

R. J. Matyi

Keyword(s):

Thin Film ◽

Structural Information ◽

Structural Characteristics ◽

Diffraction Theory ◽

Simulation Software ◽

X Ray Diffraction ◽

Theory Analysis ◽

Dynamical Diffraction ◽

X Ray ◽

Kinematic Limit

A modified version of the statistical dynamical diffraction theory (mSDDT) permits full-pattern fitting of high-resolution X-ray diffraction scans from thin-film systems across the entire range from fully dynamic to fully kinematic scattering. The mSDDT analysis has been applied to a set of model SiGe/Si thin-film samples in order to define the capabilities of this approach. For defect-free materials that diffract at the dynamic limit, mSDDT analyses return structural information that is consistent with commercial dynamical diffraction simulation software. As defect levels increase and the diffraction characteristics shift towards the kinematic limit, the mSDDT provides new insights into the structural characteristics of these materials.

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The Structural and Optical Properties of Al Doped ZnO Thin Film

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.727-728.280 ◽

2015 ◽

Vol 727-728 ◽

pp. 280-283

Author(s):

Ping Cao ◽

Yue Bai ◽

Zhi Qu

Keyword(s):

Thin Film ◽

Optical Properties ◽

Absorption Spectroscopy ◽

Sol Gel ◽

Zno Thin Film ◽

X Ray Diffraction ◽

Structural And Optical Properties ◽

X Ray ◽

Uv Emission ◽

Doped Zno

Al doped ZnO thin film have been prepared by a sol-gel method. The structural, and optical properties of the sample were investigated. X-ray diffraction and X-ray absorption spectroscopy analyses and UV absorption spectroscopy analyses indicate that Al3+ substitute for Zn2+ without changing the wurtzite structure. With the Al doping, the visible emission increased and the UV emission decreased, which is attributed to the increase of O vacancies and Zn interstitials.

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Annealing Characteristics of Electron Beam Evaporated Magnesium Oxide Thin Film

MRS Proceedings ◽

10.1557/proc-471-87 ◽

1997 ◽

Vol 471 ◽

Cited By ~ 2

Author(s):

Y. C. Kang ◽

J. B. Baik ◽

B. H. Lee ◽

J. H. Choi ◽

J. M. Kim ◽

...

Keyword(s):

Thin Film ◽

Electron Beam ◽

Treatment Time ◽

Diffraction Method ◽

Life Time ◽

Oxide Thin Film ◽

X Ray Diffraction ◽

Boundary Area ◽

X Ray ◽

Electron Microscopes

ABSTRACTThe effect of the annealing characteristics of MgO thin film, which is used as a protecting layer and known to play an important role to life time and lower the firing voltage in AC plasma displays, was investigated experimentally. MgO films were deposited on glass substrates by an electron beam evaporation method and annealed at different temperatures with varying heat treatment time. The characteristics of the crystallization and surface morphology of MgO films were changed by various annealing conditions, confirmed with X-ray diffraction method and scanning and transmission electron microscopes (SEM & TEM). With increasing annealing time and higher temperature, the intensity of the X-ray diffraction peak and the crystalline grain size of MgO increases. With the change of crystallinity and the decrease in grain boundary area, it is considered that the characteristics of firing voltage and life time of the plasma display panel can be improved with appropriate annealing process.

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The EFfects of Elemental Sequence and Pairing on Interdiffusion and Phase Formation of Al-Ge-Ni Ohmic Contacts for (001) GaAs

MRS Proceedings ◽

10.1557/proc-300-261 ◽

1993 ◽

Vol 300 ◽

Author(s):

W. V. Lampert ◽

T. W. Haas ◽

Paul H. Holloway

Keyword(s):

Thin Film ◽

Phase Formation ◽

Thermal Processing ◽

Ohmic Contacts ◽

Treatment Time ◽

X Ray Diffraction ◽

X Ray ◽

Ohmic Behavior ◽

Contact Metallization ◽

Time Required

ABSTRACTThe growth sequence of Al, Ge, and Ni metals has been shown to dramatically affect the amount of heat treatment time required to convert the ohmic contact metallization from Schottky to ohmic behavior. Interpretation of interdiffusion and phase formation of the Al-Ge, Al-Ni, or Ni-Ge thin film couples were measured. Auger depth profiles and thin film X-ray diffraction were used to determine interdiffusion and phase formation resulting from various types of thermal processing. The effects of interdiffusion and formation of phases such as Ni-Ga, Ni-As, Ni-Ga-Ge, and Ni-As-Ge from the two element metallizations on GaAs will be used to explain the origin of ohmic behavior for the ternary Al-Ge-Ni contacts to GaAs.

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The Study of SiC Surface Cleaning by Hydrogen Plasma

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.473.61 ◽

2013 ◽

Vol 473 ◽

pp. 61-64

Author(s):

Su Hua Chen

Keyword(s):

Plasma Treatment ◽

Photoelectron Spectroscopy ◽

Treatment Time ◽

Hydrogen Plasma ◽

Surface Cleaning ◽

Plasma System ◽

Xps Spectra ◽

X Ray ◽

Surface Oxides ◽

Before And After

The SiC surfaces were cleaned by the hydrogen plasma with ECRPEMOCVD plasma system at low temperature of 200°C, after the traditional wet cleaning. The surfaces were investigated by RHEED and X-ray Photoelectron Spectroscopy before and after hydrogen plasma treatment. The RHEED imagines showed that the SiC surfaces by hydrogen plasma treatment were more flatter than the SiC surfaces by the traditional wet cleaning, and we found the result that more treatment time, more flatter. The XPS spectra examinations indicated that the surface oxides reduced obviously and the C/C-H compounds on the SiC surface were removed by hydrogen plasma treatment, so the antioxidant ability of the SiC surface was improved.

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Sensing of Ethanol with Nanosize Fe-ZnO Thin Films

Journal of Nanomaterials ◽

10.1155/2009/316035 ◽

2009 ◽

Vol 2009 ◽

pp. 1-3 ◽

Cited By ~ 16

Author(s):

G.-H. Kuo ◽

H. Paul Wang ◽

H. H. Hsu ◽

James Wang ◽

Y. M. Chiu ◽

...

Keyword(s):

Thin Film ◽

Thin Films ◽

High Sensitivity ◽

Zno Thin Films ◽

Zno Thin Film ◽

X Ray Diffraction ◽

X Ray ◽

Main Compound ◽

Doped Zno ◽

Very High

Sensing of ethanol with iron doped ZnO (Fe-ZnO) thin films has been studied in this work. By X-ray diffraction spectroscopy, it is found that ZnO is the main compound in the low-iron (<10%) doped ZnO thin films.ZnFe2O4is also found as 20–50% of iron are doped on the thin films. The 5% Fe-ZnO thin film has a very high sensitivity (Rair/Rethanol>70) to 1000 ppm of ethanol at 300 K. It seems that iron can promote the sensivity of the ZnO thin film. The thin film doped with a greater amount (20–50%) of iron has, however, a much less sensitivity (<15) to ethanol. The chemical interactions between oxygen of ethanol and zinc on the Fe-ZnO thin film cause changes of the bond distances of Zn–O and Fe–O in the thin films to 1.90 and 1.98 Å which can be restored to 1.91 and 1.97 Å, respectively, in the absence of ethanol.

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