Influence of Au on Ge Crystallization and Its Thermoelectric Properties in a Au-induced Ge Crystallization Technique

Poly-crystalline Ge (pc-Ge) thin films were prepared on a SiO2/Si substrate using Au-induced crystallization (GIC) of amorphous Ge (a-Ge) with an annealing temperature around the eutectic point of Au-Ge alloy system (361ÂºC) in order to shorten the annealing time. Bilayer thin films of Au (20 nm)/a-Ge (100 nm) were used as a precursor material and annealed at 300, 400, and 500 ÂºC for 60 min, which successfully leads to the formation of pc-Ge layers. Characterizing the prepared Ge layers, the crystallographic properties indicated that the metal catalyst Au plays a notable role of enhancing both the crystallization and the island formation of Ge layers. It was also shown that the pc-Ge hardly contains Au atoms. Therefore, the Seebeck coefficient was hardly influenced by Au atoms since they do not act as a carrier source. In addition, the thermal conductivity of the pc-Ge film prepared by the GIC method was higher than that formed without Au, which is not due to the Au catalyst itself but due to the crystallinity of Ge film enhanced by the Au atoms.

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Effect of Precursor Sol Ageing on Sol-Gel Derived Ruthenium Oxide Thin Films

MRS Proceedings ◽

10.1557/proc-606-211 ◽

1999 ◽

Vol 606 ◽

Cited By ~ 4

Author(s):

S. Bhaskar ◽

S. B. Majumder ◽

P. S. Dobal ◽

R. S. Katiyar ◽

A. L. M. Cruz ◽

...

Keyword(s):

Thin Films ◽

Room Temperature ◽

Annealing Temperature ◽

Sol Gel ◽

Ruthenium Oxide ◽

Precursor Solution ◽

Silicon Substrates ◽

Solution Deposition ◽

Precursor Material ◽

Afm Analysis

AbstractIn the present work we have optimized the process parameters to yield homogeneous, smooth ruthenium oxide (RuO2) thin films on silicon substrates by a solution deposition technique using RuCl3.×.H2O as the precursor material. Films were annealed in a temperature range of 300°C to 700°C, and it was found that RuO2 crystallizes at a temperature as low as 400°C. The crystallinity of the films improves with increased annealing temperature and the resistivity decreases from 4.86µΩ-m (films annealed at 400°C) to 2.94pµΩ (films annealed at 700°C). Ageing of the precursor solution has a pronounced effect on the measured resistivities of RuO2 thin films. It was found that the measured room temperature resistivities increases from 2.94µΩ-m to 45.7µΩ-m when the precursor sol is aged for aged 60 days. AFM analysis on the aged films shows that the grain size and the surface roughness of the annealed films increase with the ageing of the precursor solution. From XPS analysis we have detected the presence of non-transformed RuCl3 in case of films prepared from aged solution. We propose, that solution ageing inhibits the transformation of RuCl3 to RuO2 during the annealing of the films. The deterioration of the conductivity with solution ageing is thought to be related with the chloride contamination in the annealed films.

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Role of Annealing Temperature, Time, and Composition on the Fabrication of Aux Pd1−x Nanostructures on c-Plane Sapphire by the Solid-State Dewetting of Bimetallic Thin Films

IEEE Transactions on Nanotechnology ◽

10.1109/tnano.2018.2801943 ◽

2018 ◽

Vol 17 (2) ◽

pp. 325-331 ◽

Cited By ~ 4

Author(s):

Puran Pandey ◽

Sundar Kunwar ◽

Mao Sui ◽

Sushil Bastola ◽

Jihoon Lee

Keyword(s):

Thin Films ◽

Solid State ◽

Annealing Temperature ◽

Temperature Time

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Role of thickness and annealing temperature on the structural ordering in vacuum evaporated antimony selenide thin films

Energy Sources Part A Recovery Utilization and Environmental Effects ◽

10.1080/15567036.2019.1654566 ◽

2019 ◽

pp. 1-9

Author(s):

M. Malligavathy Rajakumar ◽

R. T. Ananth Kumar ◽

D. Pathinettam Padiyan

Keyword(s):

Thin Films ◽

Annealing Temperature ◽

Structural Ordering ◽

Antimony Selenide

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Aluminium Induced Crystallization of Amorphous Silicon via Solution Derived Catalyst

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.481.3 ◽

2013 ◽

Vol 481 ◽

pp. 3-6

Author(s):

Ian Yi Yu Bu

Keyword(s):

Annealing Temperature ◽

Preparation Method ◽

Low Cost ◽

Vacuum Solution ◽

Solution Process ◽

X Ray Diffraction ◽

X Ray ◽

Induced Crystallization ◽

Probe Measurements

In this paper, aluminum induced crystallization (AIC) was studied by examining the effect of using solution derived AlCl3 catalyst. Such catalyst preparation method offers possibility of low-cost, non-vacuum solution process and allows examination of the role of alumina on the AIC process. The deposited AIC films were examined by using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), Raman spectroscopy, X-ray diffraction (XRD) and four probe measurements. It was found that AIC process is highly dependent on annealing temperature and can occur at annealing temperatures above 500°C through Al2O3 formation. Based on the presented data, a possible growth model is proposed to clarify AIC mechanism.

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Role of annealing temperature on electrical and optical properties of Al-doped ZnO thin films

Ceramics International ◽

10.1016/j.ceramint.2014.11.081 ◽

2015 ◽

Vol 41 (3) ◽

pp. 3968-3974 ◽

Cited By ~ 15

Author(s):

Osman Gürbüz ◽

Sadık Güner

Keyword(s):

Thin Films ◽

Optical Properties ◽

Annealing Temperature ◽

Zno Thin Films ◽

Electrical And Optical Properties ◽

Doped Zno

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Effect of Annealing Temperature on the Structure, optical and Electronic Properties of \(\text{TiO}_{2}\) Made by Thermal Treatment of \(\text{Ti}\)

Communications in Physics ◽

10.15625/0868-3166/24/2/3702 ◽

2014 ◽

Vol 24 (2) ◽

pp. 155

Author(s):

Dang Tran Chien ◽

Pham Duy Long

Keyword(s):

Thin Films ◽

Thermal Treatment ◽

Annealing Temperature ◽

Rutile Phase ◽

Nanoporous Structure ◽

X Ray Diffraction ◽

Uv Illumination ◽

Optical And Electronic Properties ◽

Nanoparticle Structure ◽

20 Nm

In this work, TiO\(_{2}\) nanocrystalline thin films were obtained through evaporating Ti films by Electron Beam Deposition (EBD) followed by thermal treatment. The deposition speed of Ti thin fims was carried out at 0.15 nm/s and 1 nm/s. The results show that after annealing at 450\(^\circ\)C for 8 h, the obtained TiO\(_{2}\) thin films have nanoparticle structure with grain size of 20 nm for the Ti thin film deposited at the rate of 1nm/s, whereas at the a deposition rate of 0.15 nm/s, the TiO\(_{2}\) has a nanorod structure with the rod length of 300 -- 400 nm. At 700\(^\circ\)C for 8 h, the rutile phase was formed. At annealing temperature of 450\(^\circ\)C, all the samples are close to the stress free TiO\(_{2}\). The band gap of TiO\(_{2}\) thin films decreased with annealing temperature in both doposition rate of Ti thin films. The response of the films annealed at 450\(^\circ\)C presented a faster rise and fall in photocurrent under UV illumination on and off interval. Nanoporous structure TiO\(_{2}\) shows photoelectronic property better than that of nanorod structure. The obtained TiO\(_{2}\) films were characterized by X-ray diffraction (XRD) and a field emission scanning electron microscope (FE-SEM). The TiO\(_{2}\) films were used in a photo-electrochemical (PEC) cell as a working electrode and a platinum electrode as a counter electrode. The electrolyte solution contains 1 M KCl and 0.1 M Na\(_{2}\)S.

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Investigation of the Structural, Optical and Electrical Properties of AgInSe2 Thin Films

Ibn AL- Haitham Journal For Pure and Applied Science ◽

10.30526/31.1.1848 ◽

2018 ◽

Vol 31 (1) ◽

pp. 37 ◽

Cited By ~ 2

Author(s):

Iman Hameed Khudayer ◽

Bushra Hashem Hussein Ali ◽

Mohammed Hamid Mustafa ◽

Ayser Jumah Ibrahim

Keyword(s):

Thin Films ◽

Surface Roughness ◽

Grain Size ◽

Electrical Properties ◽

Room Temperature ◽

Annealing Temperature ◽

Optical And Electrical Properties ◽

X Ray ◽

20 Nm

The Silver1Indium1Selenide (AgInSe2) (AIS) thin1films of (3001±20) nm thickness have been1prepared2from the compound alloys2using thermal evaporation2 technique onto the glass2substrate at room temperature, with a deposition rate2(3±0.1) nm2sec-1. The2structural, optical and electrical3properties have been studied3at different annealing3temperatures (Ta=450, 550 and 650) K. The amount3or (concentration) of the elements3(Ag, In, Se) in the prepared alloy3was verified using an energy dispersive3x-ray spectrometer (EDS)3technology. X-ray diffraction3analysis shows that AIS alloy prepared as (powder) and the thin films3are polycrystalline of tetragonal3structure with preferential orientation3(112). The crystalline3size increases as a function3of annealing temperature. The atomic force3microscope (AFM) technique was used to examine3the topography and estimate3the surface roughness, also the average grain3size of the films. The results show3that the grain size increases3with annealing3temperature. The optical4band gap of the films lies4in the range 1.6-1.9 eV. The films4appear to be4n-type indicating that the electrons4as a dominant charge4carrier. The electrical conductivity4increases with a corresponding4increase in annealing4temperature.

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Study of the Influence of Annealing Temperature on the Structural and Optical Properties of ZnTe Prepared by Vacuum Thermal Evaporation Technique

Ibn AL- Haitham Journal For Pure and Applied Science ◽

10.30526/31.1.1851 ◽

2018 ◽

Vol 31 (1) ◽

pp. 50

Author(s):

Sarmad M. Ali ◽

Alia A.A. Shehab ◽

Samir A. Maki

Keyword(s):

Thin Films ◽

Optical Properties ◽

Annealing Temperature ◽

Energy Gap ◽

Force Microscopy ◽

Glass Substrates ◽

Atomic Force ◽

High Smoothness ◽

Evaporation Technique ◽

20 Nm

The ZnTe alloy was prepared as deposited thin films on the glass substrates at a thickness of 400±20 nm using vacuum evaporation technique at pressure (1 × 10-5) mbar and room temperature. Then the thin films under vacuum (2 × 10-3 mbar) were annealing at (RT,100 and 300) °C for one hour. The structural properties were studied by using X-ray diffraction and AFM, the results show that the thin films had approached the single crystalline in the direction (111) as preferred orientation of the structure zinc-blende for cubic type, with small peaks of tellurium (Te) element for all prepared thin films. The calculated crystallite size (Cs) decreased with the increase in the annealing temperature, from (25) nm before the annealing to (21) nm after the annealing. The images of atomic force microscopy of all thin films appeared a homogenous structure and high smoothness through roughness values that increased slightly from (1.4) nm to (3.4) nm. The optical properties of the ZnTe at (RT,100 and 300) °C were studied transmittance and absorbance spectrum as a function of the wavelength. The energy gap was found about (2.4) eV for the thin films before the annealing and increased slightly to (2.5) eV after annealing at 300 °C

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The Formation Mechanism and Model of the Surface Nanoscale Kirkendall Effect on Au Catalyst Island/GaAs Substrate by Thermal Vapor-Liquid-Solid Method with Two-Step Temperature Mode

Catalysts ◽

10.3390/catal9121072 ◽

2019 ◽

Vol 9 (12) ◽

pp. 1072 ◽

Cited By ~ 1

Author(s):

Khac An DAO ◽

Hong Trang Pham ◽

Tien Thanh Nguyen ◽

Anh Tuan Phan

Keyword(s):

Formation Mechanism ◽

Kirkendall Effect ◽

Metal Catalyst ◽

Special Role ◽

Au Catalyst ◽

Vapor Liquid Solid ◽

Outward Diffusion ◽

Potential Applications ◽

Vapor Liquid

The Surface Nanoscale Kirkendall Effect is an important part of the Kirkendall effect, and has special role in the formation of surface nano material configurations. It can also cause faults in interconnection contact systems, yet this kind of effect has not yet been identified and studied in detail. Based on the obtained experimental results, this paper proposes a formation mechanism and model of the mixed-surface nanoscale Kirkendall effect formed by the role of Au metal catalyst islands/strips on a GaAs surface using the thermal Vapor-Liquid-Solid method. The diffusion of Ga, As, O atoms and the absorption of O atoms from a low-vacuum ambient into Au droplets forming surface nanoscale Au/Ga/O clusters leaves behind vacancies and voids; this process results in the nanoscale Kirkendall effect. In addition, the outward diffusion of the surface nanoscale Au/Ga/O clusters leaving behind bare GaAs holes in place of the former Au island forms the surface Kirkendall effect. Consequently, the combination of the two mentioned effects forms a new kind of KE, the so-called Surface Nanoscale Kirkendall Effect. This effect is generated either partly or completely, depending on the technological conditions. Accompanying this effect, the different configurations of nanomaterials have grown in number. The outward diffusion of surface nanoscale Au/Ga/O clusters was caused by the concentration of surface cluster gradients, the weakening of chemical bonds due to the accumulation of vacancies, the porosity, and pit-etching beneath the Au island. The diffusivity of surface Au/Ga/O clusters is numerically estimated. Its values vary from 2 × 10−10 to 10−11 m2/s. Potential applications of the surface nanoscale Kirkendall effect, making use of its advantages, limitations and disadvantages, are also discussed and proposed.

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