Sharing of secondary electrons by in-lens and out-lens detector in low-voltage scanning electron microscope equipped with immersion lens.
To understand secondary electron (SE) image formation with in-lens and out-lens detector in low-voltage scanning electron microscopy (LV-SEM), we have evaluated SE signals of an in-lens and an out-lens detector in LV-SEM. From the energy distribution spectra of SEs with various boosting voltages of the immersion lens system, we revealed that the electrostatic field of the immersion lens mainly collects electrons with energy lower than 40eV, acting as a low-pass filter. This effect is also observed as a contrast change in LV-SEM images taken by in-lens and out-lens detectors.
Kumagai
Kazuhiro
K
Graduate School of Pure and Applied Science, University of Tsukuba, 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan. KUMAGAI.kazuhiro@nims.go.jp
Sekiguchi
Takashi
T