CHARACTERIZATION OF DISLOCATIONS IN GERMANIUM SUBSTRATES INDUCED BY MECHANICAL-STRESS

Dislocations are observed in germanium crystals (9 degrees off axis to ward the [011] direction) that have undergone plastic deformation. Opt ical microscopy reveals that the substrates exhibit a crosshatch patte rn, consisting of ridges and trenches that extend in the [011] and [01 (1) over bar] directions. Further characterization of these features with scanning tunneling microscopy shows that they consist of bands of steps. These bands are created when a group of dislocations emerge on to the crystal surface from the bulk. The dislocations are determined to be type (a/2)[011]. (C) 1998 American Institute of Physics. [S0003- 6951(95)04334-4].