Cornrn n cat on Germanium-Doped Gallium Arsenide Tunnel

This communicat ion describes a method for the preparat ion of degenerate p- type GaAs using ger-man ium as the dopant. Tunne l diodes fabr icated from this mater ia l exhibit electrical characterist ics identical to those fabricated from Zn-doped mate-rial. Recent work ( t-4) has indicated that group IV elements have an amphoter ic electrical behavior in I I I-V compounds. For example, german ium wil l act as either a donor or an acceptor in GaAs de-pending on whether it occupies, respectively, a gal l ium or an arsenic site in the lattice. The net electrical act ivity of the german ium wil l be deter-mined by the fract ion of german ium atoms at each of the two sites. The fract ion of donors wi l l be in