Synthesis and characterization of carbon nanowalls by ICP CVD using aluminium acetylacetonate precursor
Duisburg, Essen (2012), XIV, 111 Bl.
Dissertation / Fach: Physik
Fakultät für Physik
A new method of synthesis of carbon nanowalls using acetylacetonate as metal organic precursor is presented. The films were deposited in ICP-CVD generated argon plasma by varying gas flow rate, plasma power, substrate temperature and reactor pressure. The precursor-feeding rate into the plasma chamber was controlled by the argon gas flow. No catalyst or other carbon gas source was added to deposit such structures. The wall size of CNWs was strongly influenced by the aluminium content present inside the film, plasma parameters like substrate temperature, plasma power and gas flow rate. The smallest wall size observed was 5nm. All films were analysed using SEM, XRD, Raman and TEM techniques in order to characterize the morphology of the samples. XPS, EDX, SIMS, and NRA were used for chemical analysis. The structuring of CNW layers was performed successfully with a pulsed power laser. The resulting cathodes exhibited fairly aligned and efficient field emission (FE) at onset fields for 1 nA of 10-20 V/μm. Local FE measurements of selected CNW patches revealed promising maximum current values up to about 100 μA. Aluminium oxide films were observed when deposited in oxygen/argon plasma.