Enhancement in Thermoelectrical Power Factor of N-Type Si₈₀Ge₂₀ Alloys

Influences of the carrier concentration and mobility of heavily doped n-type Si₈₀Ge₂₀ alloys on the thermoelectrical power factor are investigated. The experimental results indicate that thermoelectrical power factors of 32--36μWcm^-1K^-2 could be consistently achieved with carrier concentrations of 2.1--2.9×10²⁰cm^-3 and carrier mobilities of 36--40cm²V^-1s^-1. However, many samples with suitable carrier concentrations do not always have high mobilities and high power factors. Some possible explanations for this behaviour are discussed.