Crystalline beta-C3N4 films deposited on metallic substrates by microwave plasma chemical vapor deposition

Carbon nitride films were grown on poly-crystalline metallic substrates, su ch as Ta, Mo and Pt, by the microwave plasma chemical vapor deposition (MPC VD) method. The deposited films were examined by scanning electron microsco pe (SEM), energy dispersive X-ray (EDX) and XRD. SEM observations show that the films deposited on Pt substrates consisted of small crystalline grains , while the morphology of the films on the other substrates were irregular. X-ray diffraction experiments show that metallic carbide or nitride are fo rmed in films deposited on Ta and Mo but not on Pt substrates. However, cha racteristic peaks of crystalline beta-C3N4 and alpha-C3N4 can be seen in fi lms deposited on all three substrates. EDX analysis show that N/C ratios ca n be as high as 4/3 for carbon nitride films deposited on Pt under optimize d growth conditions. (C) 1999 Elsevier Science S.A. All rights reserved.