The development of in situ high-resolution electron microscopy

Progress in introducing high-resolution electron microscopy at controlled elevated temperatures is described. Initial work involved the study of dynamic events in materials like cadmium telluride which can be heated to a sufficient degree by the imaging beam. However, for reproducible experiments the temperature must be carefully controlled and measured, and this involves a heating specimen holder. Results achieved recently this way on a variety of substances including CdTe, GaAs, Si, GaAs-Ti, GaAs-Ni, Si- Mo and Si-Ti, are reported. To derive information pertinent to bulk behavior both the manner of an in situ reaction and its kinetics should be compared with those for specimens prepared from macroscopic materials treated ex situ. For interface reactions in semiconductor materials it is found that events typical of the bulk can be recorded under high-resolution conditions in a large proportion of cases.