Structural and surface changes in glassy carbon due to strontium implantation and heat treatment

Abstract There are still questions around the microstructure of glassy carbon (GC), like the observation of the micropores. These were proposed to explain the low density of GC. This paper explains the effect of ion bombardment (200 keV Sr + , 1 × 10 16 Sr + /cm 2 at RT) on the microstructure of GC. TEM and AFM show that micropores in pristine GC are destroyed leading to densification of GC from 1.42 g/cm 3 to 2.03 g/cm 3 . The amorphisation of glassy carbon was also not complete with graphitic strands embedded within the GC. These were relatively few, as Raman analysis showed that the Sr implantation resulted in a typical amorphous Raman spectrum. Annealing of the sample at 900 °C only resulted in a slight recovery of the GC structure. AFM and SEM analysis showed that the surface of the sample became rougher after Sr implantation. The roughness increased after the sample was annealed at 600 °C due to segregation of Sr towards the surface of the GC. SEM measurements of a sample with both implanted and un-implanted edges after annealing at 900 °C, showed that the high temperature heat treatment did not affect the surface topography of un-irradiated GC.