DETECTION OF POINT-DEFECT INHOMOGENEITIES IN III-V SEMICONDUCTORS BY SCANNING-DLTS

As a rule all deep level investigations start from the assumption of a more or less homogeneous lateral distribution of the levels over the sample area under investigation. The scanning-DLTS method, originally proposed by Petroff and Lang, as implementation of the electron probe excitation mechanism to the DLTS detection method allows such investigations to be carried out. In a scanning electron microscope (SEM) the sample is placed on a cryostat and electrically connected with a DLTS spectrometer. The block diagram of a system that is based on the SEM BS 300 from Tesla is presented, and special investigations and results are reported.