Thermoelectric power of metallic Si:(P,B) at very low temperatures
Physikalisches Institut, Universität Karlsruhe - D-76128
Accepted: 18 December 1995
The thermoelectric power S(T) of metallic compensated Si:(P,B) samples with carrier concentration N = 13.0 and has been measured between 0.1 and 10 K. For the more heavily doped sample, the low-T data can be well described with a negative T -linear nearly-free–electron diffusion term and a T3 phonon-drag contribution. The sample closer to the metal-insulator transition (critical concentration for the compensation ratio of this sample), exhibits a sign change of S(T) at 0.35 K, becoming positive towards lower T . The ensuing maximum (since is attributed to Kondo scattering by local magnetic moments. This is supported by the suppression of this maximum and recovery of a linear S(T) in a magnetic field of .
PACS: 71.30.+h – Metal-insulator transitions / 71.55.Cn – Elemental semiconductors / 72.20.Pa – Thermoelectric effects
© EDP Sciences, 1996