Beam-induced crystallization of amorphous Me-Si-C (Me = Nb or Zr) thin films during transmission electron microscopy
نویسندگان
چکیده
We report that an electron beam focused for high resolution imaging rapidly initiates observable crystallization of amorphous Me-Si-C films. For 200-keV electron irradiation of Nb-Si-C and Zr-Si-C films, crystallization is observed at doses of ~2.8*10 and ~4.7*10 e /nm, respectively. The crystallization process is driven by atomic displacement events, rather than heating from the electron beam as in-situ annealing (400-600 °C) retains the amorphous state. Our findings demand a critical analysis of alleged amorphous and nanocrystalline ceramics including reassessing previous reports on nanocrystalline Me-Si-C films for possible electron-beam-induced crystallization effects.
منابع مشابه
Me-Si-C (Me= Nb, Ti or Zr) Nanocomposite and Amorphous Thin Films
...............................................................................................................i Preface................................................................................................................iii Included papers ..................................................................................................v Acknowledgements................................
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