The influence of different substrates on field emission properties of graphene-diamond composite films
Diamond film is considered as a promising field electron emitter cathode material due to the high ther-mal conductivity,negative electron affinity,low work function and long-term stability.It is difficult to peel off the diamond film without destroying its structural integrity after the diamond film is deposited on the substrate.Therefore,the diamond film and substrate are generally tested as a whole during the field emission properties measurement.However,there is an interface barrier between the substrate and the diamond film,and the influ-ence of the interface barrier on the field emission properties can not be ignored.At present,there are relatively few studies on the influence of the interface between diamond film and substrate on field emission properties,which needs more attention and research.In this work,the graphene-diamond composite films are fabricated by microwave plasma chemical vapor deposition(MPCVD),which the single crystalline silicon,metal niobium and metal molybdenum are used as substrates,respectively.The microstructure and composition of graphene-dia-mond composite films were characterized and the field emission properties were studied.The results show that different substrates have significant effects on the field emission properties of the composite films.The compos-ite films fabricated on metal niobium substrate show low turn on field(E0=2.5 V/μm)and high emission cur-rent density(J@5.3 V/μm=1.9 mA/cm2).This study provides a new idea for obtaining graphene-diamond composite films with better field emission properties.
electron field emissiongraphene-diamond composite filmsdifferent substratesMPCVD
万方数据
维普
