GROWTH OF CARBON FIBRES, SHEETS AND TUBES ON DIAMOND FILMS UNDER HIGH POWER PLASMA ETCHING CONDITIONS

摘要

The application of diamond as a plasma facing material for fusion reactors can be limited by unknown reactions between diamond and thechamber materials transported by the plasma. Transformation of diamond to other structures can cause problems such as contamination ofthe plasma with loose particles or retention of gases. We have seen that diamond thin films are eroded under hydrogen plasma etching,but if silicon is present the growth of various carbon structures on diamond films is observed. We have produced carbon with differentmorphologies on diamond films including fibres, sheets with flower-like shapes and tubes and proposed growth mechanisms based on theresults of Scanning Electron Microscopy, X-Ray Photoelectron Spectroscopy and Raman Spectroscopy.Sample surfaces contain silicon and are oxidised having COO and CO groups as seen by XPS analysis. Raman analyses revealed a spectrumtypical for graphite combined with that from diamond that remains on the surface after hydrogen bombardment. The results of this studyshow the experimental conditions in which carbon fibres, sheets and tubes are produced under high-power hydrogen etching of diamondfilms and open the possibility to other applications such as catalysts, sensors and the production of electrodes.