Thermoelectric properties of SiC thin films

Direct Measurement of Optical Absorption for Si–Ge–Au Amorphous Thin Films by Using Photoacoustic Spectroscopy

“…18) This indicates that Series-A-0 has a very short interval amorphous layered structure. That is, as-deposited films have a layered structure, [7][8][9][10][11][12][13][14] although electrons can pass through barrier layers by tunneling because of the films' very short artificial interval. Therefore, the PA spectrum is not affected by ''multi-quantum well (MQW)'' directly.…”

“…The sample preparation procedures are almost the same as those reported previously. [7][8][9][10][11][12][13][14] Au (High Purity Chemicals; 99.9% up) doped Ge (Furuuchi Chemicals; 99.99% up) and Si (High Purity Chemicals; 99.999%) superlattice thin films were prepared by an independent shutter operation with the simultaneous evaporation of these two components onto glass substrates in an ultrahigh vacuum system. The base pressure of the stainless steel chamber with a liquid N 2 shroud was approximately $10 À8 Pa, but increased up to $10 À6 Pa during the operation of two electron beam guns.…”

“…[3][4][5][6] We have already reported Si-Ge-Au amorphous superlattice thin films that show an extremely large power factor. [7][8][9][10][11] The maximum power factor of such films reaches approximately 7 W/(mÁK 2 ) at around 800 K, which is extremely large compared with those of other materials reported.…”

“…We attempt to clarify the change from a quasi-stable amorphous phase to another quasi-stable amorphous phase or to a mixture of microcrystals, which are related to extremely high thermoelectric properties, by comparing the optical absorption spectra as functions of the number of annealing cycles. [7][8][9][10][11][12][13][14]…”

Photoacoustic Spectra and Thermoelectric Properties of Amorphous Si/Au/Ge/Au Superlattice

“…7,8) The maximum power factor of such films reaches approximately 7 W/mK 2 at around 800 K. The large thermoelectric power of the samples is not from the superlattice structure but from mixtures of Si/Ge amorphous phases and/or microcrystals. [7][8][9][10][11] In general, superlattice structures have mainly two effects. One is the multi quantum well effect and the other is the strain effect.…”