Effect of substrate type and thickness on power output of silicon nanowire thermoelectric device

The effects of substrate type and thickness on the performance of silicon nanowire thermoelectric device were investigated. It is found that the increase in the etching time results in the longer nanowires and larger power output. The substrate type has no significant effect on the power generation. Under the same recipes, the I-V characteristics and power outputs were examined for two different thicknesses of N-type substrate. For the thin substrate, the better performance can be attributed to low thickness ratio of silicon bulks to silicon nanwire array and series resistance. In brief, the substrate thickness, silicon nanowire length and nanowire number density are major elements for optimized thermoelectric power generation.