Evaluation of the micro-phase diagram near the stoichiometric composition of the Bi/sub 2/Te/sub 3/-Sb/sub 2/Te/sub 3/ alloys

Bi/sub 2/Te/sub 3/-Sb/sub 2/Te/sub 3/ alloys were prepared by the mechanical alloying method and sintered at the temperatures ranging from 50 to 550/spl deg/C to ensure the phase equilibrium at low temperatures. A micro-phase diagram near the stoichiometric composition was evaluated with the carrier concentration which was estimated from the values of the Seebeck coefficient. Singular properties of the Seebeck coefficient and the electrical resistivity observed at the composition of 20% Bi/sub 2/Te/sub 3/-80% Sb/sub 2/Te/sub 3/ were also discussed.