  This study explores the potentialities of Scanning Thermal Microscopy (SThM)
technique as a tool for measuring thermal transporting properties of
carbon-derived materials issued from thermal conversion of organic polymers,
such as the most commonly known polyimide (PI), Kapton. For quantitative
measurements, the Null Point SThM (NP-SThM) technique is used in order to avoid
unwanted effects as the parasitic heat flows through the air and the probe
cantilever. Kapton HN films were pyrolysed in an inert atmosphere at
temperatures up to 1200{\deg}C to produce carbon-based residues with varying
degree of conversion to free sp2 disordered carbon. The thermal conductivity of
carbon materials ranges from 0.2 to 2 Wm-1K-1 depending on the temperature of
the carbonization process (varied between 500{\deg}C and 1200{\deg}C). In order
to validate the applicability of NP-SThM approach to these materials, the
results were compared to those obtained with the three more traditional
techniques, namely photo-thermal radiometry, flash laser analysis and
micro-Raman thermometry. It was found that NP SThM data are in excellent
agreement with previous work using more traditional techniques. We used the
NP-SThM technique to differentiate structural heterogeneities or imperfections
at the surface of the pyrolysed Kapton on the basis of measured local thermal
conductivity.
