Surface investigation of carbon films: from diamond to graphite

In the present work, a detailed spectroscopic investigation of carbon in different crystalline forms from diamond to graphite was carried out. The spectra of photoemission peak, plasmon losses and X‐rays‐excited C KLL were studied in order to characterize the carbon phase in different samples. In addition, a method for determination of sp 2 /sp 3 ratio from the first derivative of Auger C KLL spectrum was employed. The obtained results indicated that carbon photoemission peak for sp 2 and sp 3 configurations is characterized by the same value of binding energy. The peaks of plasmon losses and Auger KLL transition were more diagnostic than C 1s photoemission peak, permitting to distinguish the sp 2 and sp 3 configurations. For intermediate situation, which is present in diamond‐like carbon (DLC), characterized by a mixture of sp 2 and sp 3 states, the spectra were very similar to the carbon‐black, whereas single‐wall carbon nanotubes (CNT) were containing about 50% sp 2 states.