Accurate Analysis of Group III–V Compound Semiconductors by High Precision Phase-Shifting Electron Holography and Possibility to High Speed Observation

Abstract

Phase-shifting electron holography (PS-EH) is one of the phase imaging TEM techniques and provides quantitative and precise evaluation of electromagnetic fields in functional materials. Here, we applied this technique to visualize dopant distribution (10¹⁶/10¹⁷/10¹⁸/10¹⁹ atoms/cm³) in a n-type GaN model sample. The all layers were clearly observed with enough signals. We also succeeded in observing significant changes of electric potential, field and charge distributions around GaAs p-n junctions by biasing PS-EH. In addition, we applied compressive sensing technology to the PS-EH and found that a signal/noise ratio in hologram improved drastically, which leads to 500 times higher speed observation using in situ PS-EH. In this paper, the above results are described.