Magnetoresistivity tensor components have been measured as a function of orientation and magnetic field dependence in antimony and its p-type alloys with tin and germanium at 77 K, 196 K and 300 K. A special minimization program has been used to obtain the model parameters (the components of electron and hole mobility tensors, the carrier densities and the tilt angles of the Fermi surface ellipsoids) for a two band, multivalley ellipsoidal Fermi surface. The validity of the field dependent tensor method has first been checked on antimony itself; the model parameters of antimony found from components of field dependent tensors have been compared with those obtained using the low field method of Oktu; and Saunders (1967). The results show that the field dependent tensor theory can be extended to the treatment of galvanomagnetic effects of antimony and its alloys. The existence of Umkehr effect in the magnetoresistivity of antimony and its alloys has been established; this phenomenon can be understood on the basis of field dependent tensor description transport properties. Then using the field dependent tensor method, extensive details of the temperature and concentration dependence of the carrier mobilities in antimony and its alloys have been obtained. It has been found that each tin or germanium atom removes one electron. The carrier mobilities in antimony alloys are dominated by ionized impurity scattering; the Born approximation is a better fit for these alloys than for bismuth-lead alloys (Bhargava 1967). The tilt angles of Fermi surface pockets are invariant with temperature and concentration.
|Date of Award||1978|