COMPETITION OF NITROGEN DOPING AND GRAPHITIZATION EFFECT FOR FIELD ELECTRON EMISSION FROM NANOCRYSTALLINE DIAMOND FILMS

摘要

Field electron emission properties were investigated for nitrogen-doped nanocrystalline diamond films grown on Si substrates from CH{sub}4/Ar/N{sub}2 and CH{sub}4/H{sub}2/N{sub}2 gas mixtures by d.c. arc plasma CVD. Different nitrogen content in the gas mixtures and different deposition temperatures were used for the growth to get the films with different nitrogen content and microstructure. A nitrogen incorporation is promising for field electron emission from diamond films due to formation of electrical conductivity channels inside the films and changing the electron affinity on the film surface (n-doping and/or additional surface energy levels). In addition, higher growth temperature for some of the films assists to partial graphitisation of the diamond films that can improve the emission too. So a set of the films without nitrogen was grown at high temperatures as well.