Thermoelectric properties of 50-nm-wide n- and p- type silicon nanowires

For the evaluation of thermoelectric properties in silicon nanowires (SiNWs), thermoelectric test structures are manufactured, including 50-nm-wide n- and p-type SiNWs, micro-heater and temperature sensors using a conventional lithography method on 8 in. silicon wafer. For the optimization of thermoelectric properties in SiNWs, we have evaluated Seebeck coefficients and power factors of n- and p-type SiNWs by varying the nanowire length 10, 40 μm and temperature (from 310 to 450 K). The results show that the maximum Seebeck coefficients and power factors are 146.37 μ V/K , 1.15 × 10 3 W m - 1 K - 2 , 113.83 μ V/K , 0.67 × 10 3 W m - 1 K - 2 and - 113.25 μ V/K , 0.59 × 10 3 W m - 1 K - 2 for 10 , 40 μ m long p-type and 40 μ m long n-type SiNWs, respectively. The contribution of phonon-drag effect to thermoelectric power is discussed in the highly doped SiNWs.