Experimental evidence of improved thermoelectric properties at 300K in Si/Ge superlattice structures
- Research Triangle Inst., Research Triangle Park, NC (United States)
The authors have found that it may be possible to obtain significant enhancement in ZT at 300 K, over conventional bulk SiGe alloys, through the use of Si/Ge Superlattice (SL) structures. The Seebeck coefficient in Si/Ge SL structures was observed to increase rapidly with decreasing SL period with no loss of electrical conductivity. The carrier mobilities in Si/Ge SLs were higher than in a comparable thin-film Si/Ge alloy. The best power factor of the short-period Si/Ge SLs is 112.2 {micro}W/K{sup 2} cm, over five-fold better than state-of-the-art n-type, bulk SiGe alloys. Approximately a two to four-fold reduction in thermal conductivity in short-period SL structures, compared to bulk SiGe alloy, was observed. The authors estimate at least a factor of five improvement over current state-of-the-art SiGe alloys, in several Si/Ge SL samples with periodicity of {approximately}45 to 75 {angstrom}. The results of this study are promising, but tentative due to the possible effects of substrate and the developmental nature of the thermoelectric property measurements.
- Research Organization:
- Knolls Atomic Power Lab. (KAPL), Niskayuna, NY (United States)
- Sponsoring Organization:
- USDOE Assistant Secretary for Nuclear Energy, Washington, DC (United States)
- DOE Contract Number:
- AC12-76SN00052
- OSTI ID:
- 319833
- Report Number(s):
- KAPL-P-000155; K-97030; CONF-970302-; ON: DE99001878; TRN: 99:003947
- Resource Relation:
- Conference: Spring meeting of the Materials Research Society, San Francisco, CA (United States), 31 Mar - 4 Apr 1997; Other Information: PBD: Apr 1997
- Country of Publication:
- United States
- Language:
- English
Similar Records
The cross-plane thermoelectric properties of p-Ge/Si{sub 0.5}Ge{sub 0.5} superlattices
Thermoelectric properties of MBE-grown HgCdTe-based superlattices from 100K to 300K