Introduce of the Signal Detection System Using EXB
Abstract: The image contrast of the scanning electron microscope (SEM) depends on signal generation efficiency of secondary electrons (SE) and the position of the SE detector. The detector of the SEM not only detects secondary electrons but also SE signal generated by backscattered electrons (BSE). It is also difficult to observe the surface of the sample using high accelerating voltage. The realization of high resolution at low accelerating voltage was achieved by a field emission electron gun and a strong excitation type object lens. An SEM equipped with a strong excitation type objective lens includes a control function that can observe an image while adjusting SE and BSE signal with a signal detector. This paper introduces the ExB system within a snorkel type objective lens system with a controllable SE/BSE signal function.
Key words: In-lens type objective lens, Snorkel type objective lens, TTL, ExB