Seebeck Coefficient Characterization of Highly Doped n- and p-Type Silicon Nanowires for Thermoelectric Device Applications Fabricated with Top-Down Approach

Abstract

A silicon nanowire one-dimensional thermoelectric device is presented as a solution to enhance thermoelectric performance. A top-down process is adopted for the definition of 50 nm silicon nanowires (SiNWs) and the fabrication of the nano-structured thermoelectric devices on silicon on insulator (SOI) wafer. To measure the Seebeck coefficients of 50 nm width n- and p-type SiNWs, a thermoelectric test structure, containing SiNWs, micro-heaters and temperature sensors is fabricated. Doping concentration is 1.0 x 10(20) cm(-3) for both for n- and p-type SiNWs. To determine the temperature gradient, a temperature coefficient of resistance (TCR) analysis is done and the extracted TCR value is 1750-1800 PPM . K-1. The measured Seebeck coefficients are -127.583 mu V . K-1 and 141.758 mu V . K-1 for n- and p-type SiNWs, respectively, at room temperature. Consequently, power factor values are 1.46 mW . m(-1) . K-2 and 1.66 mW . m(-1). K-2 for n- and p-type SiNWs, respectively. Our results indicate that SiNWs based thermoelectric devices have a great potential for applications in future energy conversion systems.