Galvanomagnetic Properties of n-Type InSb at Low Temperatures. I. Localization of Carriers and Metallic Impurity Conduction under Zero and Weak Magnetic Fields

Abstract

The Hall coefficient and resistivity, under zero and weak magnetic fields, of n-InSb containing 1×10 13 –2×10 15 cm -3 of excess donors have been systematically investigated at liquid helium temperatures. By increasing compensating acceptors with a nearly fixed donor concentration ( N d ∼2×10 14 cm -3 , it is observed that the localization of the Hall carriers, or the metal-nonmetal transition, occurs at the excess donor concentration of ∼6×10 13 cm -3 (compensation ratio K ∼0.7) at 1.3 K. In the metallic range, the impurity concentration has been changed with a nearly fixed compensation ratio ( K ∼0.5), and it is confirmed that the impurity conduction (of metallic type) is recognized in the excess donor concentration range up to ∼4×10 14 cm -3 .