Benawra J, Donald A M, Shannon M
BSS Group, Department of Physics, Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge, U.K.
J Microsc. 2009 Apr;234(1):89-94. doi: 10.1111/j.1365-2818.2009.03151.x.
The use of a combined focused ion beam/environmental scanning electron microscope (FIB/ESEM) offers new possibilities for imaging the internal structure of complex heterogeneous polymeric samples. The use of the focused ion beam, using positively charged gallium ions in conjunction with a measured 'defocused' low-energy primary electron beam, has permitted milling through the heterostructure to be achieved in a controlled way, exposing the inner structure, without introducing significant ion beam damage/destruction into the sample. The subsequent use of the environmental scanning electron microscope for imaging the revealed internal structure has then enabled insulating polymer structures to be imaged, without charging problems. Cross-sections of a 900-nm-thick spun cast film of phase-separated polystyrene-polybutadiene blends have been successfully milled and imaged; the morphology agreeing with previous results produced using ultramicrotomy and transmission electron microscopy.
联用聚焦离子束/环境扫描电子显微镜（FIB/ESEM）为成像复杂的多相聚合物样品的内部结构提供了新的可能性。聚焦离子束利用带正电的镓离子并结合经测量的“散焦”低能一次电子束，能够以可控方式对异质结构进行铣削，从而暴露内部结构，同时不会对样品造成显著的离子束损伤/破坏。随后使用环境扫描电子显微镜对所揭示的内部结构进行成像，使得绝缘聚合物结构能够在不存在充电问题的情况下成像。已成功对相分离的聚苯乙烯-聚丁二烯共混物的900纳米厚旋铸薄膜的横截面进行了铣削和成像；其形态与先前使用超薄切片术和透射电子显微镜得到的结果一致。
