MeV Ion Beam Bombardments Effects on the Thermoelectric Properties of Zn4Sb3 / CeFe(4-x)CoxSb12 Nano-Layered Superlattices

2006 ◽  
Vol 974 ◽  
Author(s):  
S. Budak ◽  
C. C. Smith ◽  
B. Zheng ◽  
C. I. Muntele ◽  
R. L. Zimmerman ◽  
...  
Keyword(s):  
Thin Films ◽  
Thermal Conductivity ◽  
Energy Conversion ◽  
Rutherford Backscattering Spectrometry ◽  
Ion Beam ◽  
Electrical Energy ◽  
3Ω Method ◽  
Ion Beam Assisted Deposition ◽  
Before And After ◽  
Conductivity Of Thin Films

ABSTRACTWe prepared multilayers of semiconducting half-heusler β-Zn4Sb3 and skutterudites CeFe(4-x)CoxSb12 compound thin films by ion beam assisted deposition (IBAD) system for the application of thermoelectric (TE) materials. Rutherford backscattering spectrometry (RBS) was used to analyze the composition of thin films. The thin films were then bombarded by 5 MeV Si ions for generation of nanodots in the films. We measured the cross-plane thermal conductivity by a house developed 3ω-method system, cross-plane Seebeck coefficient by a (MMR) Seebeck system, and cross plane electrical conductivity of these nanolayered systems by a (MMR) Hall system before and after bombardment. Both β-Zn4Sb3 and CeFe(4-x)CoxSb12 systems have been identified as promising thermoelectric materials for the application of thermal-to-electrical energy conversion. The nanodots produced by MeV ion beam can cause significant change in both electrical and thermal conductivity of thin films, thus improving the efficiency. The MeV ion-beam bombardment resulted in decrease in the thermal conductivity of thin films and increase in the efficiency of thermal-to-electrical energy conversion.

MeV Ion-Beam Bombardment Effects on The Thermoelectric Figures of Merit of Zn4Sb3 and ZrNiSn-Based half-heusler compounds

2007 ◽  
Vol 1020 ◽  
Author(s):  
S. Budak ◽  
S. Guner ◽  
C. Muntele ◽  
C. C. Smith ◽  
B. Zheng ◽  
...  
Keyword(s):  
Thin Films ◽  
Thermal Conductivity ◽  
Seebeck Coefficient ◽  
Measurement System ◽  
Ion Beam ◽  
Electrical Energy ◽  
Figures Of Merit ◽  
Material Systems ◽  
The Cross ◽  
Conductivity Of Thin Films

AbstractSemiconducting â-Zn4Sb3and ZrNiSn-based half-heusler compound thin films were prepared by co-evaporation for the application of thermoelectric (TE) materials. High-purity solid zinc and antimony were evaporated by electron beam to grow the â-Zn4Sb3thin film while high-purity zirconium powder and nickel tin powders were evaporated by electron beam to grow the ZrNiSn-based half-heusler compound thin film. Rutherford backscattering spectrometry (RBS) was used to analyze the composition of the thin films. The grown thin films were subjected to 5 MeV Si ions bombardments for generation of nanostructures in the films. We measured the thermal conductivity, Seebeck coefficient, and electrical conductivity of these two systems before and after 5 MeV Si ions beam bombardments. The two material systems have been identified as promising TE materials for the application of thermal-to-electrical energy conversion, but the efficiency still limits their applications. The electronic energy deposited due to ionization in the track of MeV ion beam can cause localized crystallization. The nanostructures produced by MeV ion beam can cause significant change in both the electrical and the thermal conductivity of thin films, thereby improving the efficiency. We used the 3ù-method measurement system to measure the cross-plane thermal conductivity ,the Van der Pauw measurement system to measure the cross-plane electrical conductivity, and the Seebeck-coefficient measurement system to measure the cross-plane Seebeck coefficient. The thermoelectric figures of merit of the two material systems were then derived by calculations using the measurement results. The MeV ion-beam bombardment was found to decrease the thermal conductivity of thin films and increase the efficiency of thermal-to-electrical energy conversion.

Effects of MeV Si Ions Modification on the Thermoelectric Properties of SiO2/SiO2+Cu Multilayer Thin Films

2010 ◽  
Vol 1267 ◽  
Author(s):  
John Chacha ◽  
S. Budak ◽  
Cydale Smith ◽  
Marcus Pugh ◽  
Kudus Ogbara ◽  
...  
Keyword(s):  
Thin Films ◽  
Thermal Conductivity ◽  
Electrical Conductivity ◽  
Seebeck Coefficient ◽  
Ion Beam ◽  
Absolute Temperature ◽  
Conductivity Increase ◽  
Before And After ◽  
The Cross ◽  
Thermoelectric Thin Films

AbstractThe performance of the thermoelectric materials and devices is shown by a dimensionless figure of merit, ZT = S2σT/K, where S is the Seebeck coefficient, σ is the electrical conductivity, T is the absolute temperature and K is the thermal conductivity. ZT can be increased by increasing S, increasing σ, or decreasing K. We have prepared 100 alternating multi-nano layer of SiO2/SiO2+Cu superlattice films using the ion beam assisted deposition (IBAD). The 5 MeV Si ions bombardments have been performed at the different fluences using the AAMU Pelletron ion beam accelerator to make quantum clusters in the multi-layer superlattice thin films to decrease the cross plane thermal conductivity increase the cross plane Seebeck coefficient and cross plane electrical conductivity. To characterize the thermoelectric thin films before and after Si ion bombardments we have measured the cross-plane Seebeck coefficient, the cross-plane electrical conductivity, and the cross-plane thermal conductivity for different fluences.

Thermoelectric Properties of YbBiPt and YBiPt Thin Films

2008 ◽  
Vol 1100 ◽  
Author(s):  
Sadik Guner ◽  
Satilmis Budak ◽  
Claudiu I Muntele ◽  
Daryush Ila
Keyword(s):  
Thin Films ◽  
Thermal Conductivity ◽  
Electrical Conductivity ◽  
Seebeck Coefficient ◽  
Thermoelectric Properties ◽  
Figure Of Merit ◽  
Rutherford Backscattering Spectrometry ◽  
Conductivity Measurement ◽  
Electronic Energy ◽  
Before And After

AbstractMonolayer thin films of YbBiPt and YBiPt have been produced with 560 nm and 394 nm thick respectively in house and their thermoelectric properties were measured before and after MeV ion bombardment. The energy of the ions were selected such that the bombarding Si ions stop in the silicon substrate and deposit only electronic energy by ionization in the deposited thin film. The bombardment by 5.0 MeV Si ions at various fluences changed the homogeneity as well as reducing the internal stress in the films thus affecting the thermal, electrical and Seebeck coefficient of thin films. The stoichiometry of the thin films was determined using Rutherford Backscattering Spectrometry, the thickness has been measured using interferometry and the electrical conductivity was measured using Van der Pauw method. Thermal conductivity of the thin films was measured using an in-house built 3ω thermal conductivity measurement system. Using the measured Seebeck coefficient, thermal conductivity and electrical conductivity we calculated the figure of merit (ZT). We will report our findings of change in the measured figure of merit as a function of bombardment fluence.

Composition and Phase Control for Molybdenum Nitride thin Films

1994 ◽  
Vol 354 ◽  
Author(s):  
Mandar S. Mudholkar ◽  
Levi T. Thompson
Keyword(s):  
Thin Films ◽  
Energy Density ◽  
Rutherford Backscattering Spectrometry ◽  
Ion Beam ◽  
Arrival Rate ◽  
Molybdenum Nitride ◽  
Effective Energy ◽  
Film Composition ◽  
Ion Beam Assisted Deposition ◽  
Molybdenum Nitrides

AbstractMolybdenum nitrides are active and selective hydrodenitrogenation (HDN) catalysts. The catalytic properties of molybdenum nitrides were found to be dependent on the structural properties. The purpose of research described in this paper was to synthesize molybdenum nitride thin films with well defined structures and stoichiometries using ion beam assisted deposition. The films were deposited by evaporating Mo metal, and simultaneously bombarding the growing film with low energy nitrogen ions. The phase constituents of the films were determined using x-ray diffraction and the film composition was obtained by Rutherford backscattering spectrometry.The film composition and phase constituents were strong functions of the ion-to-atom arrival rate ratio, ion energy and ion angle of incidence. Differences in the film composition for different arrival rate ratios and ion angles of incidence were interpreted based on reflection and sputtering effects. Our results suggest that phase formation was governed by the effective energy density per deposited atom. Evaluation of the effective energy density per deposited atom and its physical significance in ion beam assisted deposition is discussed.

Thermal conductivity of thin films of gallium nitride, doped with aluminium, measured with 3ω method

2020 ◽  
Vol 101 ◽  
pp. 106105 ◽  
Author(s):  
Alexandra Filatova-Zalewska ◽  
Zenon Litwicki ◽  
Tadeusz Suski ◽  
Andrzej Jeżowski
Keyword(s):  
Thin Films ◽  
Thermal Conductivity ◽  
Gallium Nitride ◽  
3Ω Method ◽  
Conductivity Of Thin Films

Effect of MeV Si Ion Bombardment on Thermoelectric Characteristics of Sequentially Deposited SiO2/AuxSiO2(1-x) Nanolayers

2006 ◽  
Vol 929 ◽  
Author(s):  
S. Budak ◽  
B. Zheng ◽  
C. Muntele ◽  
Z. Xiao ◽  
I. Muntele ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Seebeck Coefficient ◽  
Electric Conductivity ◽  
Figure Of Merit ◽  
Rutherford Backscattering Spectrometry ◽  
Cooling System ◽  
Ion Beam ◽  
Cluster Structure ◽  
Thermoelectric Efficiency ◽  
Before And After

ABSTRACTWe made 50 and 100 periodic nano-layers of electro-cooling system consisting of SiO2/AuxSiO2(1−x) super lattice with Au layer deposited on both side as metal contact using Ion Beam Assisted Deposition (IBAD) system. The deposited multi-layer films have a periodic structure consisting of alternating layers where each layer is between 1-10 nm thick. The ultimate objective of this research is to tailor the figure of merit of layered structures used as thermoelectric generators. The super lattices were then bombarded by 5 MeV Si ion at different four fluences to form nano-cluster structure. The film thickness and stoichiometry were monitored by Rutherford Backscattering Spectrometry (RBS) before and after MeV bombardments. We measured the thermoelectric efficiency of the fabricated device before and after MeV bombardments. To accomplish this we measured the cross plane thermal conductivity by 3rd harmonic method, measured cross plane Seebeck coefficient, and measured electric conductivity using Van Der Pauw method before and after 5 MeV Si Bombardments. As predicted the electronic energy deposited due to ionization by MeV Si beam in its track produces nano-scale structures which disrupt and confine phonon transmission therefore reducing thermal conductivity, increasing electron density of state so as to increase Seebeck coefficient, and electric conductivity, thus increasing figure of merit. We will present our findings during the meeting.* Research sponsored by the Center for Irradiation of Materials, Alabama A&M University and by the AAMURI Center for Advanced Propulsion Materials under the contract number NAG8-1933 from NASA, and by National Science Foundation under Grant No. EPS-0447675.

Thermoelectric Properties of SiO2/SiO2+CoSb3Multi Nanolayered Films Modified by Me v Si ions Bombardment

2010 ◽  
Vol 1267 ◽  
Author(s):  
S. Budak ◽  
Cydale Smith ◽  
John Chacha ◽  
Marcus Pugh ◽  
Kudus Ogbara ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Electrical Conductivity ◽  
Seebeck Coefficient ◽  
Ion Beam ◽  
Absolute Temperature ◽  
Ion Beam Assisted Deposition ◽  
Conductivity Increase ◽  
Thermal Conductivity Increase ◽  
Before And After ◽  
The Cross

AbstractThe performance of the thermoelectric devices and materials is shown by a dimensionless figure of merit, ZT = S2σT/K, where S is the Seebeck coefficient, σ is the electrical conductivity, T is the absolute temperature and K is the thermal conductivity. ZT can be increased by increasing S, increasing σ or decreasing K. We have prepared 100 alternating nanolayered films of SiO2/SiO2+CoSb3 using the ion beam assisted deposition (IBAD). The 5 MeV Si ions bombardments have been performed using the AAMU Pelletron ion beam accelerator to make quantum clusters in the nanolayered superlattice films at the three different fluences to decrease the cross plane thermal conductivity, increase the cross plane Seebeck coefficient and cross plane electrical conductivity. We have characterized 100 alternating nanolayered films of SiO2/SiO2+CoSb3 before and after Si ion bombardments as we measured the cross-plane Seebeck coefficient, the cross-plane electrical conductivity, and the cross-plane thermal conductivity for three different fluences.

Cross-plane thermal conductivity of thin films characterized by Flash DSC measurement

2019 ◽  
Vol 677 ◽  
pp. 21-25 ◽  
Author(s):  
Yucheng He ◽  
Xiaoheng Li ◽  
Ling Ge ◽  
Qinyun Qian ◽  
Wenbing Hu
Keyword(s):  
Thin Films ◽  
Thermal Conductivity ◽  
Conductivity Of Thin Films

Plasmonic properties of titanium nitride thin films prepared by ion beam assisted deposition

2016 ◽  
Vol 185 ◽  
pp. 295-298 ◽  
Author(s):  
Lin-Ao Zhang ◽  
Hao-Nan Liu ◽  
Xiao-Xia Suo ◽  
Shuo Tong ◽  
Ying-Lan Li ◽  
...  
Keyword(s):  
Thin Films ◽  
Titanium Nitride ◽  
Ion Beam ◽  
Ion Beam Assisted Deposition
Sign in / Sign up

Export Citation Format

Share Document