Tunneling Current Density as a Function of Crystallographic Polarity

Publisher Website
Google Scholar
Abstract
Esaki diodes using the A and B or opposite {111} faces of zinc-doped gallium antimonide were fabricated using tin—tellurium spheres. Diodes made by alloying to the B face exhibit approximately an order-of-magnitude higher peak tunneling current density than those made by alloying to the A face. Differences are found in the junction geometries. Junctions fabricated by alloying to the B or {1̄1̄1̄} face are generally planar and delineation of these is pronounced, suggesting enhanced impurity concentration in their recrystallized regions. A or {111} face alloyed junctions are curved and tend to be obscurely delineated. The capitance per unit area of the B diodes was approximately twice that of the A diodes. Thus Jp/C values were typically 5–7 times higher for the B diodes. Calculations indicate, for typical A and B diodes, excess carrier concentrations 4.0×1018 and 1.5×1019/cm3, respectively. The higher tunneling current, the higher capacitance, and enhanced delineation of the planar B junction are apparently the effects of higher impurity concentration in the regrowth region due to the difference of the segregation coefficient of tellurium in gallium antimonide with crystallographic direction of growth.

This publication has 19 references indexed in Scilit: