Secondary electron image formation of a freestanding α-Si3N4 nanobelt

This paper presents the secondary electron (SE) image formation of freestanding insulating nanobelts of alpha-Si3N4 in scanning electron microscopy. These nanobelts in SE image appear transparent or opaque depending on the observing condition. We investigated the variation in the SE image of the nanobelt with accelerating voltage and scan rate. The behavior of the SE emission was analyzed by considering the amount of transmitting electrons and charging effect. We revealed that the SEs from both front and back side of the nanobelt and those from the specimen holder affect the image formation. The contribution of these SEs to the image was confirmed by using Monte Carlo simulation. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.3692972]