The Experimental Research On The Dielectrophoretic Assembly And Contact Resistance Of Carbon Nanotubes

Due to the unique structural features,carbon nanotubes(CNTs)have been adopted in wide research and application in electronics,chemistry,biology,etc.Especially the quasi one dimensional structure characteristics,high conductivity and current carrying capacity make it possible for CNTs to be used into research and manufacture of microelectronic components as functional elements and interconnects.There are inevitable problems to precisely assemble CNTs onto the electrode gap and to reduce the higher contact resistance between CNTs and electrodes.The dielectrophoresis(DEP)has been used to assemble CNTs,and the alternating current(AC)flow has been applied to reduce the contact resistance.It's a widely applied technology to assemble CNTs by DEP.Compared with the use of electronic microscope probe and directional growing way,DEP embodies such advantages as higher efficiency,clean and pollution-free.Through summarizing the performance and structure of CNTs,the application prospect of CNTs was examined.The instruments and experimental process of CNT assembly by DEP were introduced.Through the DEP assembly of CNTs,the main influence factors have been confirmed,and they are the concentration of the CNT solution,the amplitude of the applied AC voltage and the time duration of the applied field.The contact resistance was reduced by applying AC current onto electrodes,during which the voltage amplitude,frequency,and time duration of the AC power were controlled.The orthogonal experiment method has been applied to analyze the experiment data.The results prove that the Joule heat can reduce the contact resistance effectively.The orders of influence factors were summarized.In order to improve the degree of automation of DEP assembly and reduce the contact resistance,the control program was written using Lab VIEW.The control program was used to control LCR meter to realize the automation control for initialization,parameter setting,data extraction,data analysis and processing,data storage,etc.Using the control program,after the completion of CNT assembly,the experiment of reduction of contact resistance can be directly executed without other operations.This program has realized successive process of CNT assembly and the reduction of contact resistance.