Thermoelectric Power Factor of Low Dimensional Silicon Nanowires
نویسندگان
چکیده
We analyze the thermoelectric power factor in ultra-narrow low-dimensional silicon nanowires (NWs) by employing atomistic considerations for the electronic structures and linearized Boltzmann transport theory. We consider different transport orientations and both n-type and p-type NWs. We show that the NW properties are highly anisotropic, especially for p-type, and as the diameter is reduced from D=12nm (bulk-like) down to D=3nm (1D-like), changes appear in the dispersions of the NWs, that can affect the power factor (σS). We show that the conductivity has a stronger influence on the power factor compared to the Seebeck coefficient under geometrical changes. In the case of p-type NWs, bandstructure changes through confinement can improve the carrier velocities and result in power factor improvements.
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Thermoelectric Power Factor of Narrow Silicon Nanowires from Atomistic Considerations
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