IMPURITY GROUND-STATES OF SUBSTITUTIONAL SILVER ATOMS IN GE1-XSIX CRYSTALS

The activation energies for acceptor states of substitutional Ag, atom s in lattice sites in Ge1-xSix crystals (0 less than or equal to x les s than or equal to 0.3) have been determined by Hall-effect measuremen ts. The activation energy for acceptor states of Ag-s increases linear ly with the silicon concentration. In crystals with x less than or equ al to 0.6, the Ag-s behaves as a three-state acceptor, as in germanium . At higher Si concentrations in Ge1-xSix and also in silicon itself, Ag-s is a two-state acceptor. Questions related to the distribution of Ag-s acceptor states in Ge1-xSix due to the random distribution of th e components of the matrix are discussed. (C) 1995 American Institute of Physics.