Influence of resonant tunneling on the imaging of atomic defects on InAs(110) surfaces by low-temperature scanning tunneling microscopy

摘要

We have used a low-temperature scanning tunneling microscope (STM) to studythe surface of heavily doped semiconductor InAs crystals. The crystals arecleaved in situ along the (110) plane. Apart from atomically flat areas, wealso observe two major types of atomic scale defects which can be identified asS dopant atoms and as As vacancies, respectively. The strong bias voltagedependence of the STM image of the impurities can be explained in terms ofresonant tunneling through localized states which are present near theimpurity.