Exploration And Research Of Graphene-Carbon Nanotube Heterojunction Applied To Micro-Interconnect

With the rapid development of technology,integrated circuits have entered the nano age,and the reduction in feature size has made interconnection lines a major bottleneck affecting the performance of integrated circuits.As the feature size gradually decreases,the resistivity of the copper interconnect gradually increases,and the loss and delay of the circuit make an urgent need for a material that can replace copper as an interconnect.Graphene and carbon nanotubes as the most promising candidate materials to replace copper interconnects have been theoretically and practically studied by many scholars.Based on their excellent performance in terms of maximum current density,thermal conductivity,and electron mean free path,the thesis combines these two materials to study the performance of interconnects formed by two different heterostructures.The main research contents are as follows:1.Two different structures of graphene-carbon nanotube heterojunction and different preparation methods are analyzed and discussed.2.Established equivalent circuit models of single-walled metallic carbon nanotubes,single-layered metallic graphene layer,single-walled metallic carbon nanotube bundle and multiple-layered metallic graphene layer,and extracted their respective electrical performance parameters.Provide a theoretical basis for the subsequent use of this material as a micro-interconnect and performance evaluation.3.Based on the parameters predicted by ITRS,the interconnection line parameters were extracted for the vertical graphene-carbon nanotube heterojunction structure and the horizontal heterojunction structure,and for the first time under the process sizes of 32,22,and 14 nm.The time delays of the interconnects of the two heterostructures were simulated and analyzed.The effects of process size,interconnect length,and carbon nanotube diameter on the delay time of two heterojunction interconnects were discussed.At the same time,the two heterojunction structure interconnects are compared with copper interconnects.The results show that when the length of the interconnection is fixed,the horizontal heterojunction structure interconnection has always been superior to Cu in the delay of 22 nm process size Interconnects,and the vertical heterojunction structure interconnects at 22 nm can have better time delay than Cu interconnects,and the two heterojunction structure interconnects at 14 nm process size have always been superior to Cu interconnects in time delay.The advantages of the two heterojunction structures will become more and more obvious as the process size decreases,and the advantages of the vertical heterojunction structure will become more obvious as the interconnect line length increases.4.Successfully prepared for the growth of graphene-carbon nanotube heterojunction structure: the transfer of graphene and the growth of carbon nanotube array with controllable morphology on the silicon wafer.This thesis explores and studies the application of graphene-carbon nanotube heterojunction structures in micro-interconnections,and provides a reference for the possibility of replacing existing copper interconnects with excellent electrical properties in the future.