Hostname: page-component-848d4c4894-4hhp2 Total loading time: 0 Render date: 2024-05-14T18:01:13.467Z Has data issue: false hasContentIssue false

Solid-State and Vacuum Thermionic Energy Conversion

Published online by Cambridge University Press:  01 February 2011

Ali Shakouri
Affiliation:
ali@soe.ucsc.edu, University of California at Santa Cruz, Electrical Engineering, Baskin School of Engineering, SOE2, Santa Cruz, CA, 95064, United States
Z. Bian
Affiliation:
Baskin School of Engineering, University of California at Santa Cruz
R. Singh
Affiliation:
Baskin School of Engineering, University of California at Santa Cruz
Y. Zhang
Affiliation:
Baskin School of Engineering, University of California at Santa Cruz
D. Vashaee
Affiliation:
Baskin School of Engineering, University of California at Santa Cruz
T. E. Humphrey
Affiliation:
Baskin School of Engineering, University of California at Santa Cruz
H. Schmidt
Affiliation:
Baskin School of Engineering, University of California at Santa Cruz
J. M. Zide
Affiliation:
Materials Department, Electrical and Computer Engineering, University of California at Santa Barbara
G. Zeng
Affiliation:
Materials Department, Electrical and Computer Engineering, University of California at Santa Barbara
J-H. Bahk
Affiliation:
Materials Department, Electrical and Computer Engineering, University of California at Santa Barbara
A. C. Gossard
Affiliation:
Materials Department, Electrical and Computer Engineering, University of California at Santa Barbara
J. E. Bowers
Affiliation:
Materials Department, Electrical and Computer Engineering, University of California at Santa Barbara
V. Rawat
Affiliation:
Materials Engineering, Electrical and Computer Engineering, Purdue University
T. D. Sands
Affiliation:
Materials Engineering, Electrical and Computer Engineering, Purdue University
W. Kim
Affiliation:
Mechanical Engineering Department, University of California at Berkeley
S. Singer
Affiliation:
Mechanical Engineering Department, University of California at Berkeley
A. Majumdar
Affiliation:
Mechanical Engineering Department, University of California at Berkeley
P. M. Mayer
Affiliation:
Research Laboratory of Electronics, Massachusetts Institute of Technology
R. J. Ram
Affiliation:
Research Laboratory of Electronics, Massachusetts Institute of Technology
K. J. Russel
Affiliation:
Division of Engineering and Applied Sciences, Harvard University
V. Narayanamurti
Affiliation:
Division of Engineering and Applied Sciences, Harvard University
F. A. M. Koeck
Affiliation:
Departments of Physics, Materials Science and Engineering and Electrical and Computer Eng., North Carolina State University
X. Li
Affiliation:
Departments of Physics, Materials Science and Engineering and Electrical and Computer Eng., North Carolina State University
J.-S. Park
Affiliation:
Departments of Physics, Materials Science and Engineering and Electrical and Computer Eng., North Carolina State University
J. R. Smith
Affiliation:
Departments of Physics, Materials Science and Engineering and Electrical and Computer Eng., North Carolina State University
G. L. Bilbro
Affiliation:
Departments of Physics, Materials Science and Engineering and Electrical and Computer Eng., North Carolina State University
R. F. Davis
Affiliation:
Departments of Physics, Materials Science and Engineering and Electrical and Computer Eng., North Carolina State University
Z. Sitar
Affiliation:
Departments of Physics, Materials Science and Engineering and Electrical and Computer Eng., North Carolina State University
R. J. Nemanich
Affiliation:
Robert_Nemanich@ncsu.edu, North Carolina State University, Physics Department, United States
Get access

Abstract

A brief overview of the research activities at the Thermionic Energy Conversion (TEC) Center is given. The goal is to achieve direct thermal to electric energy conversion with >20% efficiency and >1W/cm2 power density at a hot side temperature of 300–650C. Thermionic emission in both vacuum and solid-state devices is investigated. In the case of solid-state devices, hot electron filtering using heterostructure barriers is used to increase the thermoelectric power factor. In order to study electron transport above the barriers and lateral momentum conservation in thermionic emission process, the current-voltage characteristic of ballistic transistor structures is investigated. Embedded ErAs nanoparticles and metal/semiconductor multilayers are used to reduce the lattice thermal conductivity. Cross-plane thermoelectric properties and the effective ZT of the thin film are analyzed using the transient Harman technique. Integrated circuit fabrication techniques are used to transfer the n- and p-type thin films on AlN substrates and make power generation modules with hundreds of thin film elements. For vacuum devices, nitrogen-doped diamond and carbon nanotubes are studied for emitters. Sb-doped highly oriented diamond and low electron affinity AlGaN are investigated for collectors. Work functions below 1.6eV and vacuum thermionic power generation at temperatures below 700C have been demonstrated.

Type
Research Article
Copyright
Copyright © Materials Research Society 2006

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES:

1 Vashaee, D., Shakouri, A., “Improved Thermoelectric Power Factor in Metal-Based SuperlatticesPhysical Review Letter, Vol. 92, no. 10, pp. 106103–1, 2004.Google Scholar
2 Shakouri, A., “Thermoelectric, thermionic and thermophotovoltaic energy conversion” International Conference on Thermoelectrics, Clemson, NC,, pp. 492497, 2005.Google Scholar
3 Shakouri, A. and Bowers, J.E., “Heterostructure Integrated Thermionic Coolers,” Applied Physics Letters, 71, pp. 12341236, 1997.Google Scholar
4 Mahan, GD, Woods, LM.Multilayer thermionic refrigeration,” Physical Review Letters, vol. 80, no. 18, 4 pp.4016–19, May 1998.Google Scholar
5 Mahan, G.D., and Vining, C.B., J. Appl. Phys. 86, 6852 (1999);Google Scholar
Radtke, R.J., Ehrenreich, H., and Grein, C.H., Applied, J. Physics 86, 3195 (1999).Google Scholar
6 Shakouri, Ali, Labounty, Chris, Abraham, Patrick, Piprek, Joachim, and Bowers, John E., “Enhanced thermionic emission cooling in high barrier superlattice heterostructures”, Material Research Society Symposium Proceedings, Vol. 545, pp. 449458, December 1998.Google Scholar
7 Vashaee, D., Shakouri, A., Conservation of lateral momentum in heterostructure integrated thermionic coolers. Thermoelectric Materials 2001 - Research and Applications. Symposium (Materials Research Society Symposium Proceedings Vol. 691). Mater. Res. Soc., pp.131–45. Warrendale, PA, USA, 2001.Google Scholar
8 Humphrey, T.E. and Linke, H., “Power Optimisation of Thermionic DevicesJ. Phys. D. 38 2051 (2005).Google Scholar
9 Vashaee, D., Shakouri, A.. Electronic and thermoelectric transport in semiconductor and metallic superlattices. Journal of Applied Physics, vol. 95, no. 3, pp. 1233–45, 2004.Google Scholar
10 Singh, R, Vashaee, D, Zhang, Yan, Negassi, M, Shakouri, A, Okuno, Y, Zeng, Gehong, LaBounty, C, Bowers, J. Experimental characterization and modeling of InP-based microcoolers. Thermoelectric Materials 2003 - Research and Applications Symposium (Mater. Res. Soc. Symposium Proceedings Vol. 793). Mater. Res. Soc. 2004, pp. 447–53. Warrendale, PA, USA.Google Scholar
11 Vashaee, Daryoosh, Zhang, Yan, Zeng, Gehong, Chiu, Yi-Jen, and Shakouri, Ali. Cross-Plane Seebeck Coefficient Anomaly in a High Barrier Superlattice with Miniband Formation. [Conference Paper] Proceedings of the International Conference on Thermoelectrics. Adelaide, Australia, July 2004 Google Scholar
12 Bian, Zhixi, and Shakouri, Ali, “Enhanced Solid-state Thermionic Emission in Non-planar Heterostructures,” to be published in Appl. Phys. Lett. 2006.Google Scholar
13 Humphrey, T. E. and Shakouri, A., “Transport formalism for multibarrier thermionic devices,” Material Research Society Fall Meeting, Boston, MA, F7.3; manuscript under preparation.Google Scholar
14 Kim, W., Singer, S., Majumdar, A., Zide, J., Gossard, A., and Shakouri, A., 2005, “Role of nanostructures in reducing thermal conductivity below alloy limit in crystalline solids,” The 24th International Conference on Thermoelectrics, pp. 912.Google Scholar
15 Zide, J. M., Klenov, D. O., Stemmer, S., Gossard, A. C., Zeng, G., Bowers, J. E., Vashaee, D. and Shakouri, A., “Thermoelectric power factor in semiconductors with buried epitaxial semimetallic nanoparticles”, Applied Physics Letters, 87, pp.112102–1–3, September, 2005.Google Scholar
16 Kim, W., Reddy, P., Majumdar, A., Zide, J., Gossard, A., Klenov, D O, Stemmer, S, Zeng, G., Bowers, J., and Shakouri, A., 2004, “Beating the alloy limit of thermal conductivity in crystalline material,” submitted to Physical Review Letters, 2005.Google Scholar
17 Zeng, Gehong, Bowers, John E., Zide, Joshua M., Zhang, Yan and Shakouri, Ali, Kim, Woochul, Singer, Suzanne, Majumdar, Arun, Cross-plane Seebeck coefficient of ErAs:InGaAs/InGaAlAs superlattice, submitted to Applied Physics Letters 2005.Google Scholar
18 Zide, J. M., Vashaee, D., Zeng, G., Bowers, J. E., Shakouri, A., Gossard, A. C., Demonstration of electron filtering to increase the Seebeck coefficient in ErAs:InGaAs/InGaAlAs superlattices, submitted to Physical Review B, 2005.Google Scholar
19 Madan, A., Kim, I. W., Cheng, S. C., Yashar, P., Dravid, V. P., Barnett, S. A., Phy. Rev. Letters 78(9), 1743 (1997).Google Scholar
20 Abu-Jafar, M., Al-Sharif, A. I. and Qteish, A., Solid State Communications, 116, 389393 (2000).Google Scholar
21 Rawat, V. and Sands, T. TiN/GaN Metal/Semiconductor Multilayer Nanocomposites Grown by Reactive Pulsed Laser Deposition, MRS Proc. Vol 872, pp. J21.4.16 (2005).Google Scholar
22 Russell, K.J., Appelbaum, Ian, Narayanmurti, V., Hanson, M.P., and Gossard, A.C., Transverse momentum nonconservation at the ErAs/GaAs interface, Phys. Rev. B 71, 121311(R) (2005).Google Scholar
23 Narayanamurti, V, Kozhevnikov, M.BEEM imaging and spectroscopy of buried structures in semiconductors,” Physics Reports, vol. 349, no. 6, pp. 447514, 2001.Google Scholar
24 Reddy, CV, Narayanamurti, V, Ryou, JH, Dupuis, RD. “Current transport in InP/In/sub 0.5/(Al/sub 0.6/Ga/sub 0.4/)/sub 0.5/P self-assembled quantum dot heterostructures using ballistic electron emission microscopy/spectroscopy,” Applied Physics Letters, vol. 80, no. 10, pp. 1770–2, 2002.Google Scholar
25 Zhang, Yan, D, Vashaee, R, Singh, A, Shakouri, Zeng, Gehong, Chiu, Yi-Jen. Influence of doping concentration and ambient temperature on the cross-plane Seebeck coefficient of InGaAs/InAlAs superlattices. [Conference Paper] Thermoelectric Materials 2003 - Research and Applications Symposium (Mater. Res. Soc. Symposium Proceedings Vol. 793). Mater. Res. Soc. 2004, pp.5965. Warrendale, PA, USA Google Scholar
26 Yang, B., Liu, J. L., and Wang, K.L., and Chen, G.Simultaneous Measurements of Seebeck Coefficient and Thermal Conductivity Across Superlattice,” Applied Physics Letters, Vol. 80, pp. 17581760, 2002.Google Scholar
27 Zeng, Gehong, Bowers, John, Zhang, Yan, Shakouri, Ali, Zide, Josh, Gossard, Authur, Kim, Woolchul, Majumdar, Arun, “ErAs/InGaAs superlattice Seebeck coefficient”, Proceedings of the 24 th International conference on Thermoelectrics, Clemson, SC; pp. 485488, June, 2005.Google Scholar
28 Venkatasubramanian, R., Siivola, E., Colpitts, T., and O'Quinn, B., Nature 413, 597602, 2001 Google Scholar
29 Singh, Rajeev, Bian, Zhixi, Zeng, Gehong, Zide, Joshua, Christofferson, James, Chou, Hsu-Feng, Gossard, Art, Bowers, John, and Shakouri, Ali, “Transient Harman Measurement of the Cross-plane ZT of InGaAs/InGaAlAs Superlattices with Embedded ErAs Nanoparticles” Proceedings of MRS Fall Meeting, Boston, November 2005.Google Scholar
30 Bian, Zhixi, Zhang, Yan, Schmidt, Holger, Shakouri, Ali, [Conference Paper] Thin film ZT characterization using transient Harman technique, Proceedings of International Conference on Thermoelectronics, 2005.Google Scholar
31 Mayer, P. M. and Ram, R. J., ‘Thin-film Thermoelectric Generator Element Characterization,’ Proceedings of the 24th International Conference on Thermoelectrics, Clemson, S.C. pp. 265–8 (2005)Google Scholar
32 Mayer, P. M., et al. manuscript submitted to Applied Physics Letters 2006.Google Scholar
33 Zeng, Gehong, Bowers, John E., Zide, Joshua M., Gossard, Arthur C., Kim, Woochul, Singer, Suzanne, Majumdar, Arun, Singh, Rajeev, Bian, Zhixi, Zhang, Yan and Shakouri, Ali, ErAs:InGaAs/InGaAlAs superlattice thin film power generator array, submitted to APL Sept 2005.Google Scholar
34 Koeck, F. A. M., Garguilo, J. M. and Nemanich, R. J., “On the thermionic emission from nitrogen doped diamond films with respect to energy conversion,” Diamond Relat. Mater. 13, 2052 (2004).Google Scholar
35 Koeck, F. A. M., Garguilo, J. M. and Nemanich, R. J., “Emission characterization from nitrogen-doped diamond with respect to energy conversion,” Diamond Relat. Mater. 15, in press (2006).Google Scholar
36 Mecouch, W. J., Wagner, B. P., Reitmeier, Z. J., and Davis, R. F., Pandarinath, C., Rodriguez, B. J., and Nemanich, R. J., “Preparation and characterization of atomically clean, stoichiometric surfaces of AlN(0001),” J. Vac. Sci. Technol. A 23, 72 (2005).Google Scholar
37 Collazo, R., Mita, S., Schlesser, R. and Sitar, Z., “Polarity control of Nitride thin films grown by metalorganic vapor phase epitaxy,” Phys. Stat. Sol. (c) 2, No. 7, 21172120 (2005).Google Scholar
38 Mita, S., Collazo, R., Schlesser, R. and Sitar, Z., “Polarity control of GaN Films Grown by Metal Organic Chemical Vapor Deposition on (0001) Sapphire Substrates,” Mater. Res. Soc. Symp. Proc. Vol. 831, E3.20.1 (2005).Google Scholar
39 Wolter, S. D., Borca-Tasciuc, D., Chen, G., Prater, J. T., Sitar, Z., “Processing and thermal properties of highly oriented diamond thin films,” Thin Solid Films 469–70, 105111 (2004).Google Scholar
40 Smith, J.R., Nemanich, R.J., Bilbro, G.L., “The effect of Schottky barrier lowering and nonplanar emitter geometry on the performance of a thermionic energy converter,” Diamond Relat. Mater. 15, in press (2006).Google Scholar
41 Garguilo, J. M., Koeck, F. A. M. and Nemanich, R. J., Xiao, X. C., Carlisle, J. A. and Auciello, O., “Thermionic Field Emission from Nanocrystalline Diamond Coated Silicon Tip Arrays,” Phys. Rev. B 72, 165404 (2005).Google Scholar
42 Wang, Y.Y., Gupta, S., Garguilo, J.M., Nemanich, R.J., “Imaging temperature-dependent field emission from carbon nanotube films: Single versus multiwalled,” Appl. Phys. Lett. 86, 063109 (2005).Google Scholar
43 Kock, F.A.M., Garguilo, J.M., Nemanich, R.J., “Field enhanced thermionic electron emission from sulfur doped nanocrystalline diamond films,” Diamond Relat. Mater. 14, 704 (2005).Google Scholar