Impact of Phonon Drag Effect on Seebeck Coefficient in p-6H-SiC: Experiment and Simulation

The Seebeck coefficient of P-doped ultrathin Si-on-insulator (SOI) layers is investigated for the application to a highly-sensitive thermopile infrared photodetector. It is found that the Seebeck coefficient originating from the phonon drag is significant in the lightly doped region and depends on the carrier concentration with increasing carrier concentration above ~5×1018 cm-3. On the basis of Seebeck coefficient calculations considering both electron and phonon distribution, the phonon-drag part of SOI Seebeck coefficient is mainly governed by the phonon transport, in which the phonon-phonon scattering process is dominant rather than the crystal boundary scattering even in the SOI layer with a thickness of 10 nm. This fact suggests that the phonon-drag Seebeck coefficient is influenced by the phonon modes different from the thermal conductivity.

Download Full-text

PHONON-DRAG EFFECT OF ULTRA-THIN FeSi2 AND MnSi1.7/FeSi2 FILMS

Modern Physics Letters B ◽

10.1142/s0217984911027078 ◽

2011 ◽

Vol 25 (22) ◽

pp. 1829-1838 ◽

Cited By ~ 6

Author(s):

Q. R. HOU ◽

B. F. GU ◽

Y. B. CHEN ◽

Y. J. HE

Keyword(s):

Electrical Resistivity ◽

Seebeck Coefficient ◽

Single Crystals ◽

Thermoelectric Power ◽

Power Factor ◽

Low Temperatures ◽

Room Temperature ◽

Phonon Drag ◽

Drag Effect ◽

Thermoelectric Power Factor

Phonon-drag effect usually occurs in single crystals at very low temperatures (10–200 K). Strong phonon-drag effect is observed in ultra-thin β- FeSi 2 films at around room temperature. The Seebeck coefficient of a 23 nm-thick β- FeSi 2 film can reach -1.375 mV/K at 343 K. However, the thermoelectric power factor of the film is still small, only 0.42×10-3 W/m-K2, due to its large electrical resistivity. When a 27 nm-thick MnSi 1.7 film with low electrical resistivity is grown on it, the thermoelectric power factor of the MnSi 1.7 film can reach 1.5×10-3 W/m-K2 at around room temperature. This value is larger than that of bulk MnSi 1.7 material in the same temperature range.

Download Full-text

Phonon-Drag Effect on Seebeck Coefficient in Co-Doped Si Wire with Submicrometer-Scaled Cross Section

IEICE Transactions on Electronics ◽

10.1587/transele.e100.c.486 ◽

2017 ◽

Vol E100.C (5) ◽

pp. 486-489 ◽

Cited By ~ 1

Author(s):

Yuhei SUZUKI ◽

Faiz SALLEH ◽

Yoshinari KAMAKURA ◽

Masaru SHIMOMURA ◽

Hiroya IKEDA

Keyword(s):

Seebeck Coefficient ◽

Cross Section ◽

Phonon Drag ◽

Drag Effect ◽

Co Doped

Download Full-text

Ab initio optimization of phonon drag effect for lower-temperature thermoelectric energy conversion

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1512328112 ◽

2015 ◽

Vol 112 (48) ◽

pp. 14777-14782 ◽

Cited By ~ 39

Author(s):

Jiawei Zhou ◽

Bolin Liao ◽

Bo Qiu ◽

Samuel Huberman ◽

Keivan Esfarjani ◽

...

Keyword(s):

Thermal Conductivity ◽

Seebeck Coefficient ◽

Figure Of Merit ◽

Significant Contribution ◽

Phonon Drag ◽

Drag Effect ◽

Thermoelectric Energy ◽

Heavily Doped ◽

Lower Temperature ◽

First Time

Although the thermoelectric figure of merit zT above 300 K has seen significant improvement recently, the progress at lower temperatures has been slow, mainly limited by the relatively low Seebeck coefficient and high thermal conductivity. Here we report, for the first time to our knowledge, success in first-principles computation of the phonon drag effect—a coupling phenomenon between electrons and nonequilibrium phonons—in heavily doped region and its optimization to enhance the Seebeck coefficient while reducing the phonon thermal conductivity by nanostructuring. Our simulation quantitatively identifies the major phonons contributing to the phonon drag, which are spectrally distinct from those carrying heat, and further reveals that although the phonon drag is reduced in heavily doped samples, a significant contribution to Seebeck coefficient still exists. An ideal phonon filter is proposed to enhance zT of silicon at room temperature by a factor of 20 to ∼0.25, and the enhancement can reach 70 times at 100 K. This work opens up a new venue toward better thermoelectrics by harnessing nonequilibrium phonons.

Download Full-text

Phonon drag effect on Seebeck coefficient of ultrathin P-doped Si-on-insulator layers

Applied Physics Letters ◽

10.1063/1.4895470 ◽

2014 ◽

Vol 105 (10) ◽

pp. 102104 ◽

Cited By ~ 12

Author(s):

F. Salleh ◽

T. Oda ◽

Y. Suzuki ◽

Y. Kamakura ◽

H. Ikeda

Keyword(s):

Seebeck Coefficient ◽

Phonon Drag ◽

Drag Effect ◽

Insulator Layers

Download Full-text

Iron Disilicide as a Base for New Improved Thermoelectrics Creation

MRS Proceedings ◽

10.1557/proc-545-155 ◽

1998 ◽

Vol 545 ◽

Cited By ~ 3

Author(s):

M. I. Fedorov ◽

Yu. V. Ivanov ◽

M. V. Vedernikov ◽

V. K. Zaitsev

Keyword(s):

Seebeck Coefficient ◽

Temperature Dependence ◽

Optical Phonon ◽

Phonon Drag ◽

Drag Effect ◽

Iron Disilicide ◽

Very High ◽

Unusual Shape

AbstractIt is well known that the temperature dependence of Seebeck coefficient of β-iron disilicide has unusual shape that cannot be described by an ordinary theory. A theory describing such a shape is suggested. It is shown this shape can be explained by optical phonon drag effect. Very high value of ZT could be achieved in some material on the base of this effect.

Download Full-text