Key Research Of Fabrication Of Ordered Metallic Nanoparticle Array Based On Thermal Annealing

Currently,the main bottleneck in the standardization and batched controllable preparation of high performance SERS substrate.The reproducible and simple preparation method of SERS substrate with high enhancement factor has been a focus of research especially those periodic solid metallic nanostructure array substrate with nano-tip and nano-gap.Combining with evaporating deposition,spin coating self-assembly,atomic layer deposition and annealing process,a controllable template-free fabrication method was proposed based on self-assembled monolayer film sacrificial layer annealing.It simplifies the preparation program of highly ordered gold nanoparticle arrays.To analyze the performance of these SERS structures,FDTD solution was used to simulate the electromagnetic factor.The Raman spectroscopy was achieved with the 4-aminothiophenol as probe.The main contents of this dissertation are as followed:1.Vacuum evaporation techniques was combined with thermal annealing to achieve the metallic nanoparticles.Besides,the effects of temperature,film thickness,annealing time and other parameters on the gold particle morphology were discussed.2.The vacuum annealing process was combined with atomic layer deposition process and the traditional fabrication method of MEMS,the laminated golden-flower-like nanostructures were prepared.Through multiple of deposition and annealing process,controllable golden-flower-like nanostructures were achieved.Using high-resolution field emission scanning electron microscopy(SEM),the morphology features of laminated golden-flower-like nanostructure were characterized and quantitatively discussed the impact of the plated film thickness,annealing temperature and annealing time on the size and morphology of laminated golden-flower-like nanostructures.3.Combining the self-assembly process,ALD technology with annealing process,the periodically ordered monolayer and bilayer metallic nano-particle structures were prepared.In the preparation process,polystyrene(PS)sphere monolayer film serves as a sacrificial support,it induced the surface gold film transforming into metallic nanoparticles after thermal annealing.Highly ordered Au Particle on Particle structure was prepared by annealing.Meanwhile,we analyze the effect of annealing parameters,the thickness of the as-deposited film on the morphology of AuPOP array.4.We discussed the differences of the spin-coated technology on various substrate surfaces and prepared the AuPOF structure arrays by SAMSA method.The large-scale metal nanoparticle arrays were achieved on the top of metal film surface with template-free preparation method.Qualitatively analysis of the influence of Al2O3 film and the impact of different annealing parameters on the morphology features of AuPOF structure array was adoped.The Al2O3 film was verified to serve as shape conformal and separation layer.Because of the increase of temperature and annealing time,we obtain more rounded contour and more uniform size distribution of the gold nanoparticle array.5.FDTD simulation was employed to analyze the distribution of electromagnetic and calculate the electromagnetic enhancement of four as-prepared substrates.Meanwhile,we compare the impact of various Al2O3 film thickness on the electromagnetic enhancement.To investigate the SERS performance of the four metal nanoparticle structures,we use 4-aminothiophenol as probe molecular to achieve Raman spectroscopy in the experiment and evaluated SERS enhancement of four nanostructural substrates.The test results are highly in agreement with simulation results.