Extraction of temperature dependent electrical resistivity and thermal conductivity from silicon microwires self-heated to melting temperature

Temperature-dependent electrical resistivity, rho(T), and thermal conductivity, k(T), of nanocrystalline silicon microwires self-heated to melt are extracted by matching simulated current-voltage (I-V) characteristics to experimental I-V characteristics. Electrical resistivity is extracted from highly doped p-type wires on silicon dioxide in which the heat losses are predominantly to the substrate and the self-heating depends mainly on rho(T) of the wires. The extracted rho(T) decreases from 11.8 m Omega cm at room-temperature to 5.2 m Omega cm at 1690 K, in reasonable agreement with the values measured up to similar to 650 K. Electrical resistivity and thermal conductivity are extracted from suspended highly doped n-type silicon wires in which the heat losses are predominantly through the wires. In this case, measured rho(T) (decreasing from 20.5 m Omega cm at room temperature to 12 m Omega cm at 620 K) is used to extract rho(T) at higher temperatures (decreasing to 1 m Omega cm at 1690 K) and k(T) (decreasing from 30 W m(-1) K-1 at room temperature to 20 W m(-1) K-1 at 1690 K). The method is tested by using the extracted parameters to model wires with different dimensions. The experimental and simulated I-V curves for these wires show good agreement up to high voltage and temperature levels. This technique allows extraction of the electrical resistivity and thermal conductivity up to very high temperatures from self-heated microstructures. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4754795]