High carrier concentration in Mg2Si1−xSbx (0 ≤ x ≤ 0.10) prepared by a combination of liquid-solid reaction, ball milling, and spark plasma sintering

Abstract

Ternary compounds of Mg2Si1−xSbx (0 ≤ x ≤ 0.10) are prepared by a combination of liquid-solid reaction, ball milling, and spark plasma sintering. The carrier concentration of Mg2Si1−xSbx increases with the Sb content x and reaches 1.1 × 1021 cm−3 at x = 0.10, which is approximately ten times higher than that previously reported. The high carrier concentration is attributed to the facilitation of Sb-doping by ball milling and the suppression of Mg vacancy formation by short-time sintering. No decrease in the carrier concentration of Mg2Si0.90Sb0.10 is observed after annealing at 773 K for 100 h in a semi-closed system, which suggests that the compound is stable at 773 K under a high partial pressure of Mg.