Detection of characteristic signals from as-doped (<1 at.%) regions of silicon by transmission electron microscopy and convergent-beam electron diffraction.
Characteristic signals were detected from As-doped (< 1 at.%) regions of silicon by dark-field transmission electron microscopy and convergent-beam electron diffraction. A slight intensity increase was observed in 220 dark-field images, which may be explained by an increase of scattering amplitude due to the As doping. The doped region showed a much higher intensity in 004 dark-field images. The characteristic high intensity was observed for specimens with As concentrations of about 0.09-0.8 at.%. Convergent-beam electron diffraction patterns obtained from the As-doped region showed a characteristic rocking curve for 004 reflection. These characteristics should originate from incoherent elastically scattered electrons due to a static lattice distortion around the doped As atoms. The observed characteristics in dark-field images and rocking curves of the 004 reflection should be a good probe not only for investigating the concentration of doped atoms in Si lattice, but also for the amount of impurity and/or point defects in other crystalline materials.
Terauchi
Masami
M
Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan. terauchi@tagen.tohoku.ac.jp
Tsuda
Kenji
K
Kawamura
Kazuo
K