AFM INVESTIGATION OF BISMUTH DOPED SILICATE-GLASSES

Bismuth doped glasses were reduced in hydrogen atmosphere at temperatu res above 250 degrees C. This process leads to changes in stoichiometr y of the glass in the region close to the glass surface. Relatively hi gh surface conductivity of 10(-6) S allows this material to be applied to channeltron production. AFM investigations of freshly cleaved bism uth doped glasses were done in constant and friction force modes. The AFM topographical images show the presence of different concentrations of nanocrystals vs distance from the glass surface. Atomic resolution images obtained in both modes of these nanocrystals, together with XR D data, suggest that they are composed of bismuth. (C) 1997 Elsevier S cience Ltd.