Experimental Study On The Assembly And Contact Resistance Of Advanced Nano Materials

As representatives of advanced nano-materials,CNT,ZnO nanowire,and graphene have great application potentials in electronics,medicine,materials and so on.Assembly is a prerequisite for the application of these nano-materials in micro-electronics and other fields.Dielectrophoresis(DEP)has the advantages of sound simplicity,high efficiency,great stability,and extensive applicability,which makes it an ideal method for assembling nano-materials.How to reduce the high contact resistance and improve the performance of nano devices becomes an urgent problem.The assembly of graphene and ZnO nanowire has been performed by the DEP method.The effect of DEP parameters,such as the amplitude of the alternating voltage,the concentration of the suspension,and the duration of the applied electric field,on the assembly outcome is studied.With the increase of the values of the above-mentioned parameters,the results show that the number of graphene and ZnO nanowire assembled between the electrodes increases.The high contact resistance of graphene and ZnO nanowires with metal electrodes has seriously affected the performance of nanomaterials when the assembly has been finished.Thus,high temperature annealing and local Joule heating are used to reduce the contact resistance of graphene.The optimal parameter combinations for reducing the contact resistance of graphene are respectively 3V,3k Hz,360 s and 350?,10?/min,20 min for the two methods.The stability of the resistance values after treatment is analyzed.High temperature annealing method is used to reduce the contact resistance of ZnO nanowire,and the performance of ZnO nanoweire devices has been improved.The optimal parameter combination for reducing the contact resistance of ZnO nanoweire is 350?,15?/min,90 min.