Scanning tunneling microscope-cathodoluminescence (STM-CL) imaging of the GaAs/AlGaAs (110) cross-section: evaluation of spatial resolution and imaging area shift

POSTER

Abstract

We studied local optical properties of AlGaAs/GaAs multilayer structures by scanning tunneling microscope cathodoluminescence (STM-CL) spectroscopy, where low-energy ($\sim $100 eV) electrons field-emitted from STM tips were used as bright excitation sources. The STM-CL measurements were performed at the (110) cross-sectional surface of the AlGaAs/GaAs multilayer structure. We found that the field-emitted electron beam (FEEB) diameter mainly determined the spatial resolution of this system in STM-CL spectroscopy by evaluating some contributors: the thermalization length and the diffusion length of generated hot electrons. We also clarified that the shift of the STM-CL measurement position from the STM tip position was caused by the FEEB angled from the surface normal.

Authors

  • Kentaro Watanabe

    • Department of Applied Physics, School of Engineering, The University of Tokyo

  • Yoshiaki Nakamura

    • Quantum-Phase Electronics Center, Department of Applied Physics, School of Engineering, The University of Tokyo and CREST-JST

  • Shigeyuki Kuboya

    • Department of Advanced Materials Science, School of Frontier Sciences, The University of Tokyo

  • Ryuji Katayama

    • Department of Advanced Materials Science, School of Frontier Sciences, The University of Tokyo

  • Kentaro Onabe

    • Department of Advanced Materials Science, School of Frontier Sciences, The University of Tokyo

  • Masakazu Ichikawa

    • Quantum-Phase Electronics Center, Department of Applied Physics, School of Engineering, The University of Tokyo and CREST-JST