Arrhenius behavior of crystallization at up to 184 000 K/s in Ge2Sb2Te5 thin films

Zn–In–Se thin films were fabricated on the ultrasonically cleaned glass substrates masked with clover-shaped geometry by thermal evaporation of its elemental sources. Temperature-dependent conductivity characteristics of the films were investigated under dark and illuminated conditions. The semiconductor type of the films was found as n-type by thermal probe test. According to the van der Pauw technique, the dark electrical conductivity analyses showed that the variations of conductivity of unannealed and annealed at [Formula: see text]C samples are in exponential dependence of temperature. These conductivity profiles were found to be dominated by the thermionic emission at high temperature region whereas their behaviors at low temperatures were modeled by hopping theory. On the contrary, as a result of the further annealing temperatures, the surface of the samples showed semi-metallic characteristics with deviating from expected Arrhenius behavior. In addition, the temperature-dependent photoconductivity of the films was analyzed under different illumination intensities and the results were explained by the supra-linear characteristic based on the two-center recombination model.

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Focused Laser Spike Dewetting as a Rheology Method for Soft Matter Thin Films

10.26434/chemrxiv.14396330.v1 ◽

2021 ◽

Author(s):

Tianxing Ma ◽

Alex Liu ◽

Michael P. Nitzsche ◽

Kyle Buznitsky ◽

Adithya Sridhar ◽

...

Keyword(s):

Thin Films ◽

Decay Time ◽

Soft Matter ◽

Transition Process ◽

Arrhenius Behavior ◽

High Throughput Analysis ◽

Viscosity Change ◽

Characteristic Decay Time ◽

Melt Pool ◽

The Mean

<div>Focused laser spike (FLaSk) dewetting employs a localized heat source to create thermocapillary induced trench-ridge morphologies. By using a universal heating substrate to create a material independent thermal profile coupled with optical microscopy, we have studied the dewetted ridge feature for several distinct glassy thin films. The evolution of the ridge's radius over time can be modeled using stretched exponential functions to derive a maximum dewetted radius and a characteristic decay time. The characteristic decay time shows a super-Arrhenius behavior resembling viscosity change during the glass transition process. An effective viscosity is defined by balancing the thermocapillary Marangoni stress using the mean temperature in the melt pool, indicating clear signature of composition. In this way, we have demonstrated that FLaSk dewetting as a rheology</div><div>method can be employed for high-throughput analysis of glassy thin film materials at high temperature and shear.</div>

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Focused Laser Spike Dewetting as a Rheology Method for Soft Matter Thin Films

10.26434/chemrxiv.14396330 ◽

2021 ◽

Author(s):

Tianxing Ma ◽

Alex Liu ◽

Michael P. Nitzsche ◽

Yi Jin ◽

Kyle Buznitsky ◽

...

Keyword(s):

Thin Films ◽

Decay Time ◽

Soft Matter ◽

Transition Process ◽

Arrhenius Behavior ◽

High Throughput Analysis ◽

Viscosity Change ◽

Characteristic Decay Time ◽

Melt Pool ◽

The Mean

<div>Focused laser spike (FLaSk) dewetting employs a localized heat source to create thermocapillary induced trench-ridge morphologies. By using a universal heating substrate to create a material independent thermal profile coupled with optical microscopy, we have studied the dewetted ridge feature for several distinct glassy thin films. The evolution of the ridge's radius over time can be modeled using stretched exponential functions to derive a maximum dewetted radius and a characteristic decay time. The characteristic decay time shows a super-Arrhenius behavior resembling viscosity change during the glass transition process. An effective viscosity is defined by balancing the thermocapillary Marangoni stress using the mean temperature in the melt pool, indicating clear signature of composition. In this way, we have demonstrated that FLaSk dewetting as a rheology</div><div>method can be employed for high-throughput analysis of glassy thin film materials at high temperature and shear.</div>

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Polymeric Nanocomposites Membranes with High Permittivity Based on PVA-ZnO Nanoparticles for Potential Applications in Flexible Electronics

Polymers ◽

10.3390/polym10121370 ◽

2018 ◽

Vol 10 (12) ◽

pp. 1370 ◽

Cited By ~ 26

Author(s):

Roberto Ambrosio ◽

Amanda Carrillo ◽

Maria Mota ◽

Karla de la Torre ◽

Richard Torrealba ◽

...

Keyword(s):

Thin Films ◽

Dielectric Properties ◽

Low Temperature ◽

Zno Nanoparticles ◽

Flexible Electronics ◽

Poly Vinyl Alcohol ◽

Polymeric Nanocomposites ◽

Arrhenius Behavior ◽

High Permittivity ◽

Potential Applications

This study reports the optical, structural, electrical and dielectric properties of Poly (vinyl alcohol) thin films membranes with embedded ZnO nanoparticles (PVA/ZnO) obtained by the solution casting method at low temperature of deposition. Fourier Transform Infrared spectra showed the characteristics peaks, which correspond to O–H and Zn–O bonds present in the hybrid material. The X-ray diffraction patterns indicated the presence of ZnO structure into the films. The composite material showed low absorbance and a wide band of gap energy from 5.5 to 5.83 eV. The surface morphology for the thin films of PVA/ZnO was studied by Atomic Force Microscopy and Scanning Electron Microscopy. The electrical properties of the membranes were also characterized by current-voltage characteristics and the DC conductivity showed Arrhenius behavior with values of activation energy from 0.62 to 0.78 eV and maximum conductivity at 2.4 × 10−12 S/cm. The dielectric properties of the nanocomposites were measured from low to high frequencies, and the results showed a high dielectric constant (ε) in the order of 104 at low frequency and values from ε ≈ 2000 to 100 in the range of 1 KHz–1 MHz respectively. The properties of PVA/ZnO such as the high permittivity and the low temperature of processing make it a suitable material for potential applications in the development of flexible electronic devices.

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Focused Laser Spike Dewetting as a Rheology Method for Soft Matter Thin Films

10.26434/chemrxiv.14396330.v2 ◽

2021 ◽

Author(s):

Tianxing Ma ◽

Alex Liu ◽

Michael P. Nitzsche ◽

Yi Jin ◽

Kyle Buznitsky ◽

...

Keyword(s):

Thin Films ◽

Decay Time ◽

Soft Matter ◽

Transition Process ◽

Arrhenius Behavior ◽

High Throughput Analysis ◽

Viscosity Change ◽

Characteristic Decay Time ◽

Melt Pool ◽

The Mean

<div>Focused laser spike (FLaSk) dewetting employs a localized heat source to create thermocapillary induced trench-ridge morphologies. By using a universal heating substrate to create a material independent thermal profile coupled with optical microscopy, we have studied the dewetted ridge feature for several distinct glassy thin films. The evolution of the ridge's radius over time can be modeled using stretched exponential functions to derive a maximum dewetted radius and a characteristic decay time. The characteristic decay time shows a super-Arrhenius behavior resembling viscosity change during the glass transition process. An effective viscosity is defined by balancing the thermocapillary Marangoni stress using the mean temperature in the melt pool, indicating clear signature of composition. In this way, we have demonstrated that FLaSk dewetting as a rheology</div><div>method can be employed for high-throughput analysis of glassy thin film materials at high temperature and shear.</div>

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Application of Vogel-Tamman-Fulcher (VTF) model to polythiophene composite thin films

Journal of Polymer Engineering ◽

10.1515/polyeng.2011-0128 ◽

2012 ◽

Vol 32 (2) ◽

Author(s):

Dhananjay P. Deshmukh ◽

Praful D. Shirbhate ◽

Sangita S. Yawale ◽

Shrikrishna P. Yawale

Keyword(s):

Thin Films ◽

Polymer Composite ◽

Ionic Conduction ◽

Segmental Motion ◽

X Ray Diffraction ◽

Iodine Doping ◽

Arrhenius Behavior ◽

Ionic Charge ◽

Dta Studies

Abstract Synthesis of polymer composites poly (vinyl acetate) (PVAc) and polythiophene (PTh) was done by chemical oxidative method using FeCl3oxidant in methanol. Thin films with PTh-PVAc polymer composite were prepared for 5.5, 10.4, 14.9, 18.9 and 22.5 wt% of iodine as a dopant. Direct current (DC) conductivity as a function of temperature (313–363 K) was measured by the two probe method. Characterization of the sample was done via X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and thermogravimetry (TG)/differential thermal analysis (DTA). The maximum value for DC electrical conductivity was found for 10.4 wt% (σ=9.78×10-10S cm-1). The decrease in conductivity for greater iodine concentrations may be due to reduced segmental motion. The temperature dependence conductivity shows percolative behavior and a clear cross over from Vogel-Tamman-Fulcher (VTF) to Arrhenius behavior. Ionic conduction decreased with increase in the concentration of iodine, which shows ionic charge transport. XRD of the samples showed an amorphous nature. FTIR spectra showed absorption in the range 550–3600 cm-1, which indicates various bands involved in the PTh-PVAc polymer composite with iodine doping. From TG/DTA studies, it was observed that all the samples with a different wt% of iodine showed degradation in a range 75–81% when heated up to 888 K.

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Effect of Introducing Free Gaseous Radicals of Trichlorosilane and Ammonia Precursors on Growth and Characteristics of LPCVD a-SiNx Ultra Thin Films

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.829.401 ◽

2013 ◽

Vol 829 ◽

pp. 401-409

Author(s):

Armin Salmasi ◽

Eskandar Keshavarz Alamdari

Keyword(s):

Thin Films ◽

Growth Rate ◽

Surface Topography ◽

Depth Profiling ◽

Chemical Vapor ◽

Arrhenius Behavior ◽

Force Microscopy ◽

Atomic Force ◽

Pressure Chemical ◽

Rate Ratios

Preparation and characteristics of amorphous silicon nitride (a-SiNx) thin films deposited by low pressure chemical vapor deposition (LPCVD) are investigated. Free gaseous radicals of trichlorosilane (TCS) and ammonia (NH3) are produced by passing each of the precursor gases separately over Pt-Ir/Al2O3 catalyst at the temperature of 600 C. Kinetics studies of the LPCVD are carried out in different total pressures, NH3/TCS flow rate ratios and temperatures. Surface topography, chemical concentrations, growth rate and thickness are studied by Ellipsometry, x-ray photo-electron spectroscopy (XPS), atomic force microscopy (AFM) and auger depth profiling (ADP). Analysis of experiments indicates that at the temperatures between 730 C and 830 C, the growth rate of thin films follows an Arrhenius behavior with activation energy of 166.3 KJ.mol-1. The measured hydrogen contamination in a-SiNx ultra thin films is 1.05 at% which is 17 times lower than the corresponding contamination in the films produced by (PECVD) and 3.4 times lower than the contamination in the LPCVD thin films with silane (SiH4) or dichlorosilane (DCS) and Ammonia. The surface topography of the prepared films is smooth and uniform and the thickness varies between 23 and 101 nanometers.

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The study of interfacial reactions of nickel thin films on GaAs

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100074616 ◽

1983 ◽

Vol 41 ◽

pp. 156-157

Author(s):

L.J. Chen ◽

Y.F. Hsieh

Keyword(s):

Thin Films ◽

Integrated Circuits ◽

Interfacial Reactions ◽

Metal Contacts ◽

Nickel Thin Films ◽

Thin Foils ◽

The Status ◽

Si Doped ◽

Electron Microscopes

One measure of the maturity of a device technology is the ease and reliability of applying contact metallurgy. Compared to metal contact of silicon, the status of GaAs metallization is still at its primitive stage. With the advent of GaAs MESFET and integrated circuits, very stringent requirements were placed on their metal contacts. During the past few years, extensive researches have been conducted in the area of Au-Ge-Ni in order to lower contact resistances and improve uniformity. In this paper, we report the results of TEM study of interfacial reactions between Ni and GaAs as part of the attempt to understand the role of nickel in Au-Ge-Ni contact of GaAs.N-type, Si-doped, (001) oriented GaAs wafers, 15 mil in thickness, were grown by gradient-freeze method. Nickel thin films, 300Å in thickness, were e-gun deposited on GaAs wafers. The samples were then annealed in dry N2 in a 3-zone diffusion furnace at temperatures 200°C - 600°C for 5-180 minutes. Thin foils for TEM examinations were prepared by chemical polishing from the GaA.s side. TEM investigations were performed with JE0L- 100B and JE0L-200CX electron microscopes.

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Studies on Water in the Hydration Chamber of a Modified Electron Microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100069715 ◽

1970 ◽

Vol 28 ◽

pp. 544-545

Author(s):

R. C. Moretz ◽

G. G. Hausner ◽

D. F. Parsons

Keyword(s):

Thin Film ◽

Thin Films ◽

Electron Microscope ◽

Steady State ◽

Room Temperature ◽

Small Mass ◽

Equilibrium Pressure ◽

Biological Objects ◽

Mechanical Pump ◽

Differential Pumping

Use of the electron microscope to examine wet objects is possible due to the small mass thickness of the equilibrium pressure of water vapor at room temperature. Previous attempts to examine hydrated biological objects and water itself used a chamber consisting of two small apertures sealed by two thin films. Extensive work in our laboratory showed that such films have an 80% failure rate when wet. Using the principle of differential pumping of the microscope column, we can use open apertures in place of thin film windows.Fig. 1 shows the modified Siemens la specimen chamber with the connections to the water supply and the auxiliary pumping station. A mechanical pump is connected to the vapor supply via a 100μ aperture to maintain steady-state conditions.

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Nucleation and Early Growth of Sputtered thin Films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100069570 ◽

1970 ◽

Vol 28 ◽

pp. 516-517

Author(s):

Dudley M. Sherman ◽

Thos. E. Hutchinson

Keyword(s):

Thin Films ◽

Electron Beam ◽

Ion Beam ◽

Ion Source ◽

Water Cooling ◽

Stages Of Growth ◽

Lens Assembly ◽

Microscope Technique ◽

Ion Beam Sputter Deposition

The in situ electron microscope technique has been shown to be a powerful method for investigating the nucleation and growth of thin films formed by vacuum vapor deposition. The nucleation and early stages of growth of metal deposits formed by ion beam sputter-deposition are now being studied by the in situ technique.A duoplasmatron ion source and lens assembly has been attached to one side of the universal chamber of an RCA EMU-4 microscope and a sputtering target inserted into the chamber from the opposite side. The material to be deposited, in disc form, is bonded to the end of an electrically isolated copper rod that has provisions for target water cooling. The ion beam is normal to the microscope electron beam and the target is placed adjacent to the electron beam above the specimen hot stage, as shown in Figure 1.

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