Thermoelectric Properties of B12+xC3-x Thin Films Prepared by Pulsed Ion-Beam Evaporation

2001 ◽  
Vol 697 ◽  
Author(s):  
Hisayuki Suematsu ◽  
Kazuo Kitajima ◽  
Ichiro Ruiz ◽  
Tetsuo Suzuki ◽  
Weihua Jiang ◽  
...  

AbstractThin films of boron carbide (B12+xC3-x) were prepared on glass substrates by a pulsed ion-beam evaporation method. A pulsed proton beam with an energy of 1 MV (peak) and a current of 60 kA was focused on sintered B12+xC3-x targets. Ablation plasma was formed from the irradiated targets and thin films were prepared on Pyrex and SiO2 glass substrates at room temperature. From results of X-ray diffraction, the thin films consisted of a B12+xC3-x phase. Using a known relationship between the composition and the lattice parameters, the composition of B12+x1C3-x thin films was estimated to be x = 0.3 and 1.0, which were close to the nominal composition of the targets. These results indicate that B12+x1C3-x with different carbon contents has been successfully prepared by IBE without substrate heating or sample annealing. Thermoelectric properties of the thin films were measured. A B12+x1C3-x thin film with estimated composition of x =0.9 exhibited the highest power factor at room temperature among the B12+x1C3-x samples reported.

2001 ◽  
Vol 697 ◽  
Author(s):  
Hisayuki Suematsu ◽  
Tsuyoshi Saikusa ◽  
Tsuneo Suzuki ◽  
Weihua Jiang ◽  
Kiyoshi Yatsui

AbstractThin films of titanium iron (TiFe) were prepared by a pulsed ion-beam evaporation (IBE) method. A pulsed ion beam of proton accelerated at 1 MV (peak) with a pulse width of 50 ns and a current of 70 kA was focused on TiFe alloy targets. Soda lime glass substrates were placed in front of the targets. Phases in the thin films were identified by X-ray diffraction (XRD). XRD results revealed that the thin films deposited on the glass substrates consist of a TiFe phase. Crystallized Ti-Fe thin films without oxides were successfully obtained. Surface roughness of the thin film was 0.16 m m.


2009 ◽  
Vol 294 ◽  
pp. 85-92 ◽  
Author(s):  
A.A. Ibrahim

Lead sulfide (PbS) thin films were prepared by thermal evaporation onto glass substrates from PbS powder. The structure and DC electrical properties of evaporated PbS thin film sandwich structures with thicknesses (d) up to 600 nm have been investigated. X-ray diffraction studies showed that the films were crystalline, with a preferred orientation in the [111] direction. Capacitance measurements indicated that the films had a relative permittivity of 5.7. Room-temperature current density-voltage (J–V) characteristics revealed ohmic conduction below a transition voltage (Vt) and a power–law dependence with an exponent of ≈ 2 at higher voltages. This behaviour was interpreted in terms of space–charge limited conductivity controlled by an exponential distribution of traps below the conduction band edge. Further evidence for this conduction process was provided by a linear dependence of Vt upon d2. Analysis of the results yielded a room temperature electron concentration no of ≈ (3.9 – 5.4) x 109 m-3.


1994 ◽  
Vol 354 ◽  
Author(s):  
Anthony S. Nazareth ◽  
Harsh Deep Chopra ◽  
D. K. Sood ◽  
R. B. Zmood

AbstractA focussing grid broad beam Kaufman source, using argon ions on a target of nominal composition Nd2Fei4B has been employed to sputter deposit magnetic thin films of thicknesses ranging from 800 â to 1300 â on silicon-(lll) substrates at room temperature. These films were characterised for their composition depth profile by Rutherford Backscattering Spectroscopy, while x-ray diffraction was used to study the crystallographic structure. Due to a close match between (111) Si with (220) Nd2Fej4B lattice spacings, preferred crystallographic texturing was expected, and experimental results showed a greatly enhanced (220) texture. The degradation in magnetic properties was attributed to the presence of oxygen in the films as indicated by concentration depth profiles. It is premised that another significant role of oxygen may be to relieve the misfit strain across the interface by its incorporation within the Nd2Fej4B phase.


2010 ◽  
Vol 305-306 ◽  
pp. 33-37 ◽  
Author(s):  
S. Lallouche ◽  
M.Y. Debili

This work deals with Al-Cu thin films, deposited onto glass substrates by RF (13.56MHz) magnetron sputtering, and annealed at 773K. The film thickness was approximately the same 3-4µm. They are characterized with respect to microstructure, grain size, microstrain, dislocation density and resistivity versus copper content. Al (Cu) deposits containing 1.8, 7.21, 86.17 and 92.5at%Cu have been investigated. The use of X-ray diffraction analysis and transmission electron microscopy lead to the characterization of different structural features of films deposited at room temperature (< 400K) and after annealing (773K). The resistivity of the films was measured using the four-point probe method. The microstrain profile obtained from XRD thanks to the Williamson-Hall method shows an increase with increasing copper content.


2019 ◽  
Vol 17 (41) ◽  
pp. 15-28
Author(s):  
Hussain. M. Selman

BixSb2-xTe3 alloys with different ratios of Bi (x=0, 0.1, 0.3, 0.5, and 2) have been prepared, Thin films of these alloys were prepared using thermal evaporation method under vacuum of 10-5 Torr on glass substrates at room temperature with different deposition rate (0.16, 0.5, 0.83) nm/sec for thickness (100, 300, 500) respectively. The X–ray diffraction measurements for BixSb2-xTe3 bulk and thin films indicate the polycrystalline structure with a strong intensity of peak of plane (015) preferred orientation with additional peaks, (0015) and (1010 ) reflections planes, which is meaning that all films present a very good texture along the (015) plane axis at different intensities for each thin film for different thickness. AFM measurements for the thin films of BixSb2-xTe3, show that the grain size and the average surface roughness decreases with increasing of the percentage Bi for different thickness.


2012 ◽  
Vol 538-541 ◽  
pp. 154-157
Author(s):  
Peng Juan Liu ◽  
Ping Fan ◽  
Zhuang Hao Zheng ◽  
Dong Ping Zhang ◽  
Xing Min Cai ◽  
...  

Antimony (Sb) and zinc (Zn) bilayer was sputter-deposited at room temperature with various Zn contents by ion-beam sputtering and transformed into Antimony zinc after post thermal annealed at 573K for 60 min. A power factor of 6.18×10-4 W/mK2 at 473 K has been obtained when the sputtering time of the Zn was 20 minutes. The maximum Seebeck coefficient is 42.0 μVK-1. Composition analysis shows that the compound of SbZn is achieved and the small Seebeck coefficient is due to the deviation of stoichiometric.


2014 ◽  
Vol 606 ◽  
pp. 15-18
Author(s):  
Falah I. Mustafa ◽  
Mooroj Ali

InxSe1-x(x = 0.4, 0.5, 0.6) thin films are deposited at room temperature on glass substrates with thickness ~500nm by thermal evaporation technique. The X-Ray diffraction analysis showed that both the as-deposited films In2Se3and InSe (x= 0.4 and 0.5) are amorphous in nature while the as-deposited film In3Se2is polycrystalline and the values of energy gap are Eg=1.44eV for In2Se3, Eg=1.16eV for InSe and Eg=0.78eV for In3Se2. The same technique used with insert Argon gas at pressure 0.1 mbar where InxSe1-x(x = 0.4, 0.5, 0.6) thin films are deposited at room temperature on glass substrates with thickness ~100nm. The X-Ray diffraction analysis showed that the as-deposited films In2Se3are amorphous in nature while the as-deposited film InSe and In3Se2are Nanocrystalline with grain size 33nm and 55nm respectively and the values of energy gap are Eg=1.55eV for InSe and Eg=1.28eV for In3Se2. The energy gap of InSe thin films increase with Argon gas assist and phases changes from amorphous and polycrystalline to nanostructure material by thermal vacuum deposition technique.


2006 ◽  
Vol 928 ◽  
Author(s):  
E. Elangovan ◽  
P Barquinha ◽  
A Pimental ◽  
A. S. Viana ◽  
R Martins ◽  
...  

ABSTRACTThin films of molybdenum doped indium oxide (IMO) were rf sputtered onto glass substrates at room temperature. The films were studied as a function of oxygen volume percentage (OVP) ranging 1.4 - 10.0 % in the sputtering chamber. The thickness of the films found varying between 180 and 260 nm. The X-ray diffraction pattern showed the films are polycrystalline with the peaks corresponding to (222) and (400) planes and one among them showing as a preferential orientation. It is observed that the preferred orientation changes from (222) plane to (400) as the OVP increases from 1.4 to 10.0 %. The transmittance spectra were found to be in the range of 77 to 89 %. The optical band gap calculated from the absorption coefficient of transmittance spectra was around 3.9 eV. The negative sign of Hall coefficient confirmed the films were n-type conducting. The bulk resistivity increased from 2.26 × 10−3 to 4.08 × 10−1 Ω−cm for the increase in OVP from 1.4 to 4.1 %, and thereafter increased dramatically so as the Hall coefficients were not detectable. From the AFM morphologies it is evaluated that the RMS roughness of the films ranges from 0.9 to 3.2 nm.


Author(s):  
Pawan Kumar Singh

Compound III-V materials are formed when atoms from group Illb of the periodic table combine with atoms from group Vb. The resulting com pounds are both crystalline and semiconducting and contain an equal proportion of both atom types. The Indium antimonide crystal has been used for infrared applications and for the radiation detector applications. Thin films of InSb with a thickness of about 0.12 micrometer are prepared onto well-cleaned glass substrates by employing an e- beam evaporation process. Indium Antimonide thin films are grown onto well cleaned glass substrates at room temperature on cleaned glass substrate in Hind Hivac- Vacuum Coating unit under a vacuum better than 10<sup>−5</sup> Torr. X-ray diffraction studies confirm the polycrystalline of the films and the films show preferential orientation along the (111) plane. The particle size found to about 1100 micrometer of thin film. In this paper we present some of our results concerning the synthesis and crystal growth of indium antimonide compounds . To carry out the synthesis of InSb a suitable mixing furnace was designed and fabricated.


2004 ◽  
Vol 19 (3) ◽  
pp. 759-767 ◽  
Author(s):  
S. Bysakh ◽  
K. Chattopadhyay ◽  
H. Ling ◽  
J.D. Wu ◽  
C. Dong ◽  
...  

We report the synthesis of thin films of B–C–N and C–N deposited by N+ ion-beam-assisted pulsed laser deposition (IBPLD) technique on glass substrates at different temperatures. We compare these films with the thin films of boron carbide synthesized by pulsed laser deposition without the assistance of ion-beam. Electron diffraction experiments in the transmission electron microscope shows that the vapor quenched regions of all films deposited at room temperature are amorphous. In addition, shown for the first time is the evidence of laser melting and subsequent rapid solidification of B4C melt in the form of micrometer- and submicrometer-size round particulates on the respective films. It is possible to amorphize B4C melt droplets of submicrometer sizes. Solidification morphologies of micrometer-size droplets show dispersion of nanocrystallites of B4C in amorphous matrix within the droplets. We were unable to synthesize cubic carbon nitride using the current technique. However, the formation of nanocrystalline turbostratic carbo- and boron carbo-nitrides were possible by IBPLD on substrate at elevated temperature and not at room temperature. Turbostraticity relaxes the lattice spacings locally in the nanometric hexagonal graphite in C–N film deposited at 600 °C leading to large broadening of diffraction rings.


Sign in / Sign up

Export Citation Format

Share Document