CURRENT-VOLTAGE CHARACTERISTICS OF SPHERICAL-GEOMETRY SEMICONDUCTOR STRUCTURES WITH ANTIBLOCKING CONTACTS

The nonuniform electric field in crystals of spherical geometry leads to some qualitatively new features of the exclusion effect. The curren t-voltage characteristics of symmetric p(+)-p-p(+) structures become a symmetric. Upon exclusion from the periphery of the sphere toward its center, the current-voltage characteristic acquires a parabolic region i alpha V-2, due to a significant buildup of carriers in a volume of small radius. Upon exclusion from the central contact, the length of t he region with the depressed carrier density, L(e), is an anomalously weak function of the current (L(e) alpha i(1/3)). Intrinsic-conductivi ty germanium was studied experimentally at T>225 K.