MICROPROBE RHEED STM COMBINED MICROSCOPY

We have developed microprobe reflection high energy electron diffracti on combined with scanning tunneling microscope and molecular beam epit axy equipment. This combination makes it possible to study and control surface processes in the magnification range from several hundred mic rometers to the atomic scale. An electron biprism is also attached to the incident electron beam path, which produces a new kind of scanning electron microscopy called scanning interference electron microscopy. The two coherently divided electron beams created by the biprism prod uce electron interference fringes. The electron interference fringes a re used to form ultrafine periodic structures by electron-stimulated s urface reaction and to characterize electromagnetic properties of the surfaces. The formation of periodic carbon grid lines produced by the interference fringes on a GaAs surface and the study of Ge thin film g rowth on a partially Ga adsorbed Si(111) surface are described for app lication examples of the microscopy.