The Shubnikov-de Haas effect in thin films of Cd3As2 I: Crystalline films

AbstractSol-gel processing represents a promising method of fabrication for thin films of electronic ceramics which are useful in a number of packaging and device applications. In this study, the influence of acid and base catalysts on the structure of PbTiO3 gels and films (0.1-1.0μm) was investigated, for the purpose of inducing and identifying gel structures which were the most suitable as precursors for thin dielectric layers. Continuous, crack-free films, with dielectric strengths in excess of 106 V/cm were developed. Basic solutions gelled rapidly, phase separated, and were probably more crosslinked than acidic gels. Acidic gels seemed more capable of polymeric rearrangement during drying, yielding denser amorphous structures with microcrystalline regions. High-field dielectric constants (1 MV/m ac) in the range K=30–40, and K=160–170, were determined for amorphous and crystalline films, respectively.

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A Study of the Diffusion of Phosphorus in Ni/amorphous NiPx and a-NiPx/a-NiPy. Multilayers

MRS Proceedings ◽

10.1557/proc-205-239 ◽

1990 ◽

Vol 205 ◽

Cited By ~ 1

Author(s):

C. A. Ross ◽

L. M. Goldman ◽

J. A. Barnard ◽

F. Spaepen

Keyword(s):

Thin Films ◽

Grain Boundaries ◽

Multilayer Thin Films ◽

Amorphous Films ◽

Phosphorus Diffusion ◽

X Ray ◽

A Value ◽

Crystalline Films

AbstractAn x-ray technique has been used to measure the diffusion of phosphorus in crystalline Ni/amorphous NiPx and amorphous NiPx/NiPy multilayer thin films produced by electrodeposition. The films have repeat lengths in the range 30–80Å and P contents x, y < 25at.%. A value for the interdiffusivity in amorphous NiPx is derived from measurements on fully amorphous films. The behaviour of partially crystalline films is described in terms of phosphorus diffusion into the nickel grain boundaries.

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Phase Transformations in Sol-Gel PZT Thin Films

MRS Proceedings ◽

10.1557/proc-623-185 ◽

2000 ◽

Vol 623 ◽

Cited By ~ 1

Author(s):

D.P. Eakin ◽

M.G. Norton ◽

D.F. Bahr

Keyword(s):

Thin Films ◽

Heat Treatment ◽

Room Temperature ◽

Structural Changes ◽

Sol Gel ◽

Ex Situ ◽

Ambient Conditions ◽

Crystalline Films ◽

In Situ Heating

AbstractThin films of PZT were deposited onto platinized and bare single crystal NaCl using spin coating and sol-gel precursors. These films were then analyzed using in situ heating in a transmission electron microscope. The results of in situ heating are compared with those of an ex situ heat treatment in a standard furnace, mimicking the heat treatment given to entire wafers of these materials for use in MEMS and ferroelectric applications. Films are shown to transform from amorphous to nanocrystalline over the course of days when held at room temperature. While chemical variations are found between films crystallized in ambient conditions and films crystallized in the vacuum conditions of the microscope, the resulting crystal structures appear to be insensitive to these differences. Significant changes in crystal structure are found at 500°C, primarily the change from largely amorphous to the beginnings of clearly crystalline films. Crystallization does occur over the course of weeks at room temperature in these films. Structural changes are more modest in these films when heated in the TEM then those observed on actual wafers. The presence of Pt significantly influences both the resulting structure and morphology in both in situ and ex situ heated films. Without Pt present, the films appear to form small, 10 nm grains consisting of both cubic and tetragonal phases, whereas in the case of the Pt larger, 100 nm grains of a tetragonal phase are formed.

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Growth of Highly Oriented Zinc Oxide Thin Films by Plasma Enhanced Chemical Vapor Deposition

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.321-323.1687 ◽

2006 ◽

Vol 321-323 ◽

pp. 1687-1690 ◽

Cited By ~ 1

Author(s):

Hee Joon Kim ◽

Dong Young Jang ◽

Prem Kumar Shishodia ◽

Akira Yoshida

Keyword(s):

Thin Films ◽

Zinc Oxide ◽

Chemical Vapor Deposition ◽

Vapor Deposition ◽

Photoelectron Spectroscopy ◽

Visible Region ◽

Chemical Vapor ◽

Zno Films ◽

X Ray ◽

Crystalline Films

In the paper, zinc oxide (ZnO) thin films are deposited by plasma enhanced chemical vapor deposition (PECVD) at different substrate temperatures. The ZnO films are characterized by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The analysis results indicate that highly crystalline films with high orientation can be obtained at a substrate temperature of 300 oC with 50 ml/min flow rate from Diethylzinc (DEZ). Furthermore, the investigation of optical property shows that ZnO films are transparent, and the peak transmittance in the visible region is as high as 85%.

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Thin films-preparation, structure and properties. Metal crystallites grown in MgO single crystalline films.

NIPPON KAGAKU KAISHI ◽

10.1246/nikkashi.1987.1988 ◽

1987 ◽

pp. 1988-1994

Author(s):

Kazuhiro MIHAMA

Keyword(s):

Thin Films ◽

Structure And Properties ◽

Single Crystalline ◽

Crystalline Films

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ZrC Thin Films Grown by Pulsed Laser Deposition

MRS Proceedings ◽

10.1557/proc-780-y3.13 ◽

2003 ◽

Vol 780 ◽

Author(s):

V. Craciun ◽

D. Craciun ◽

J. M. Howard ◽

R. K. Singh

Keyword(s):

Thin Films ◽

Pulsed Laser Deposition ◽

Photoelectron Spectroscopy ◽

Pulsed Laser ◽

Surface Region ◽

Laser Deposition ◽

X Ray Diffraction ◽

X Ray ◽

Si Substrates ◽

Crystalline Films

AbstractZrC thin films were grown on Si substrates by the pulsed laser deposition (PLD) technique. X- ray photoelectron spectroscopy, x-ray diffraction and reflectivity, variable angle spectroscopic ellipsometry, and four point probe measurements were used to investigate the composition, density, thickness, surface morphology, optical and electrical properties of the grown structures. It has been found that crystalline films could be grown only by using fluences above 6 J/cm2 and substrate temperatures in excess of 500 °C. For a fluence of 10 J/cm2 and a substrate temperature of 700 °C, highly (100)-textured ZrC films exhibiting a cubic structure (a=0.469 nm) and a density of 6.7 g/cm3 were deposited. The use of a low-pressure atmosphere of C2H2 had a beneficial effect on crystallinity and stoichiometry of the films. All films contained high levels of oxygen contamination, especially in the surface region, because of the rather reactive nature of Zr atoms.

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Novel thin films of titanium dioxide particles synthesized by a sol-gel process

Journal of Materials Research ◽

10.1557/jmr.1995.3068 ◽

1995 ◽

Vol 10 (12) ◽

pp. 3068-3078 ◽

Cited By ~ 50

Author(s):

V.J. Nagpal ◽

R.M. Davis ◽

S.B. Desu

Keyword(s):

Thin Films ◽

Titanium Dioxide ◽

Sol Gel ◽

Particle Surface ◽

Composite Films ◽

Visible Region ◽

Silicon Substrates ◽

Transparent Films ◽

Sol Gel Process ◽

Crystalline Films

Novel thin films of ultrafine titanium dioxide particles dispersed in a matrix of hydroxypropylcellulose (HPC) polymer have been made on quartz and silicon substrates. The titanium dioxide particles were made by the hydrolysis and condensation of titanium tetraethoxide (TEOT) in solutions of HPC in a mixture of ethanol and water. HPC controlled the particle size by adsorbing at the particle surface during the growth process and generating repulsive steric forces. The TiO2/HPC composite films were transparent in the visible region and completely blocked ultraviolet radiation at 300 nm. These films were crack-free and uniform in composition and thickness. Transparent films of amorphous TiO2 were made by burning out the HPC at 500 °C. These films were highly uniform and had no macroscopic cracks. X-ray diffraction revealed a transition to the anatase form upon sintering at 600 °C. A film sintered at 700 °C had a porosity of 38%. The crystalline films remained transparent until they densified at 800 °C.

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Preparation of LiTaO3 Nano-Crystalline Films by Sol-Gel Process

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.531-532.446 ◽

2012 ◽

Vol 531-532 ◽

pp. 446-449 ◽

Cited By ~ 1

Author(s):

Jun Gou ◽

Jun Wang ◽

Ze Hua Huang ◽

Ya Dong Jiang

Keyword(s):

Thin Films ◽

High Performance ◽

Detection System ◽

Sol Gel ◽

Precursor Solution ◽

Film Material ◽

Nano Crystalline ◽

Sol Gel Process ◽

Crystalline Films ◽

P Type

Lithium tantalite (LiTaO3) thin film material shows good feasibility and potential for the application of high-performance detection system. In this paper, sol-gel process of LiTaO3 thin films on p-type (111) silicon substrates was described. Stable precursor solution with a desired viscosity was obtained using lithium acetate (LiAc) and tantalum ethoxide (Ta(OC2H5)5) as starting materials. Heat treatment process was optimized to fabricate LiTaO3 films of high crystallinity. Higher crystalline quality films were obtained when each spin-coating process was followed by an annealing operation. Microstructures and crystallization properties of LiTaO3 thin films were further studied. Nano-crystalline films were obtained after annealing at 700 °C for 5 min. The experimental results indicated that the crystallinity and mean grain size of LiTaO3 thin films were proportional to the film thickness.

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Improved Routes towards Solution Deposition of Indium Sulfide Thin Films for Photovoltaic Applications:

MRS Proceedings ◽

10.1557/proc-692-h9.33.1 ◽

2001 ◽

Vol 692 ◽

Author(s):

Kuveshni Govender ◽

David Smyth-Boyle ◽

Paul O'Brien

Keyword(s):

Thin Films ◽

Electronic Spectroscopy ◽

Indium Sulfide ◽

Solution Deposition ◽

Glass Substrates ◽

Photovoltaic Applications ◽

Crystalline Films ◽

Temperature Solution ◽

Ph Range ◽

Deposited Films

AbstractConditions necessary for the reproducible deposition of pristine In2S3 thin films on TO-glass substrates by low temperature solution deposition have been identified. Baths containing carboxylic acids yield adherent, specular and crystalline films, within a defined pH range, dependent on the particular acid employed. Films have been characterised by XRD, SEM, XPS and electronic spectroscopy. As–deposited films were found to crystallise as tetragonal β-In2S3, no evidence for incorporation of hydroxy-indium species was found by XPS measurements.

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The Effects of Substrate Temperature on Optical Properties and Surface Morphology of Nickel Phthalocyanine Thin Films Grown by Organic Evaporator System

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.55-57.593 ◽

2008 ◽

Vol 55-57 ◽

pp. 593-596 ◽

Cited By ~ 1

Author(s):

P. Inchidjuy ◽

Supakorn Pukird ◽

J. Nukeaw

Keyword(s):

Thin Films ◽

Surface Morphology ◽

Substrate Temperature ◽

Absorption Spectra ◽

X Ray Diffraction ◽

Electron Energy Level ◽

Nickel Phthalocyanine ◽

Structure Surface ◽

Crystalline Films ◽

Xrd Patterns

Thin films of Nickel Phthalocyanine (NiPc) are prepared at a base pressure of 10-6 mbar using Organic Evaporator System. The films are deposited onto the glass substrate at various temperatures of 100 0C, 120 0C, 140 0C and 160 0C. Crystalline of NiPc thin films was investigated by X-ray diffraction (XRD) spectroscopy. XRD patterns exhibit to become aggravated crystalline films as monoclinic structure. Surface morphology of NiPc thin films was characterized by field emission scanning electron microscope (FE-SEM). FE-SEM micrographs indicate that fiber-like morphology of NiPc is enhanced with increasing substrate temperature. The optical absorption spectra of these thin films are measured. Present studies reveal that the Q-band of NiPc thin films appears as the change of electron energy level. Absorption spectra obtained from UV-vis of deposited NiPc are declined as the substrate temperature is risen.

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