The Research Of Preparation And Optical Properties Of Graphene Nanoarrays

Graphene plasmons possess novel optical properties such as high optical field confinement,low intrinsic loss,and easy tuning.These characteristics have developed rapidly in the basic problems and applications of surface-enhanced infrared absorption spectroscopy,with a view to showing broad application prospects in the fields of spectral detection and sensing.The excitation,regulation and application of graphene plasmons first need to realize nano-patterning processing of graphene,so as to control the energy band characteristics of graphene and make it exhibit better infrared absorption spectrum enhancement characteristics.According to research,the energy band characteristics of graphene nanoarrays are mainly determined and influenced by geometric parameters such as the shape,size and roughness of the nanoscale unit structure.Therefore,the high-precision processing of high-quality graphene nanoarrays with large surface and low surface roughness is crucial,and the research on the related processing technology and its performance regulation is of great significance.Aiming at the problem of regulating the infrared absorption spectral characteristics of nanostructured graphene arrays,the preparation process of ultra-low surface roughness graphene nanoarrays was carried out in this thesis.Microstructure characterization and spectroscopic testing of the prepared graphene nanodot array(GNDA)samples were carried out to verify the infrared absorption spectrum enhancement and tuning properties of the graphene nanoarray structure.The main research work is as follows:(1)First,based on the properties of graphene plasmons and their dispersion relationship,a simulation model of graphene nanoarrays was established.It was verified by simulation that changing the size and period of the nanoarrays could tune the enhanced infrared absorption spectrum.Then,by simulating the localized optical field enhancement effect in silver nanoparticle-doped photoresist,it provides a theoretical basis for the preparation of graphene nanoarrays.(2)Based on electron beam exposure and inductively coupled plasma etching process,a single-layer GNDA with a minimum size of 90 nm and low surface roughness was fabricated,and the appropriate exposure dose was explored.In order to prepare graphene nanoarrays with smaller size,silver nanoparticle-doped photoresist was prepared based on the laser evanescent standing wave interference lithography process based on the local optical field enhancement of metal nanoparticles.And a laser evanescent standing wave interference lithography platform is built,and the theoretical lithography line width can reach a minimum of 10 nm.(3)By testing the surface morphology and optical properties of three GNDA samples with different sizes and periods,it was found that the surface roughness of the samples could reach a minimum of 0.792 nm,and the etching quality was high.Then,through infrared and terahertz spectroscopy tests,it was found that graphene nanoarrays can achieve spectral enhancement in both infrared and terahertz bands.At the same time,it was also found that changing the size and period of the nanoarray can realize the regulation of the absorption peak of the infrared spectrum enhancement,and the enhanced infrared spectrum absorption rate can reach a maximum of 10 %.