CHARACTERIZATION OF CHARGED DEFECTS IN CDXHG1-XTE AND CDTE CRYSTALS BY ELECTRON-BEAM-INDUCED CURRENT AND SCANNING TUNNELING SPECTROSCOPY

A correlative study of the electrically active defects of CdxHg1-xTe a nd CdTe crystals has been carried out using a scanning electron micros cope/scanning tunneling microscope (SEM/STM) combined system. Charged structural and compositional defects were revealed by the remote elect ron beam induced current (REBIC) mode of the scanning electron microsc ope. The electronic inhomogeneities of the samples were analyzed with nm resolution by current imaging tunneling spectroscopy (CITS) measure ments, which showed the existence of built-in electrostatic barriers a s well as local variations of the surface band gap in the defect areas imaged by REBIC. (C) 1998 American Institute of Physics.