Controllable Fabrication Of Silicon Nanopore Arrays Assisted By Silver Nanoparticles For Chemical Etching

Due to its superior physical properties,optoelectronic properties,thermal stability,and surface properties,silicon micro/nano structures have been extensively studied in nanoelectronics,optoelectronics,energy storage,energy exchange,and bio/chemical sensors.At present,there are many methods for preparing silicon micro-nano structures,mainly including gas-liquid-solid growth,reactive ion etching,thermal evaporation,laser ablation,chemical meteorological deposition,electron beam exposure,inductively coupled plasma etching and metal-assisted chemistry Etching(MACE),etc.Among them,the MACE method has attracted much attention because of its advantages of simple manufacturing process,low cost,high efficiency,and good quality of silicon nanostructures.The essence of the MACE silicon micro-nano structure is the corrosion of the silicon matrix in the chemical reaction system.However,the structural morphology and etching rate of nanopores produced by this method are affected by many variables,and no one has systematically proposed the relationship between these variables and the etching of silicon micro-nano structures.This restricts the controllable fabrication of silicon micro-nano structures to a certain extent,and thus limits the widespread use of silicon nanopore array structures.Based on the above problems,this paper intends to study the controllable fabrication of silver nanoparticle-assisted chemical etching of silicon nanopore arrays,explore the mechanism of silver nanoparticle-assisted chemical etching,and on this basis to study the influencing factors of the structure controllable manufacturing of silicon nanopore arrays,so as to realize the controllable manufacturing of silicon nanopore arrays.Finally,it explores the detection and application of electrical performance based on silicon nanopore array sensors.The main research work of this paper is as follows:(1)The AAO template with different pore sizes and porosities and the electron beam evaporation process are first used to realize the controlled distribution of silver nanoparticle arrays with different diameters and distribution densities on the silicon substrate.Based on the etching experiment and TEM and EDS characterization,the silver nanoparticle-assisted chemical etching of the silicon nanopore crystal structure and composition was analyzed.It was concluded that no silicon oxide was formed during the oxidation of silicon,and the silver nanoparticle-assisted chemical etching Etching mechanism of silicon nanohole array prepared by etching method.Furthermore,through the morphological characterization of the silicon nanopores on the upper surface and cross-section of the silicon substrate after etching,the factors affecting the etching path of the silicon nanopores are discussed.(2)Using the single variable method,set up five different experimental groups to discuss the influence of silver nanoparticle size,etchant concentration ratio,etching time,etching solution temperature and illumination on the controllable structure of silicon nanoarray structure.Through experiments,it was found that the size of silver nanoparticles,the concentration ratio of the etchant,the etching time,the temperature of the etching solution,and the illumination are positively correlated with the etching rate of the silicon nanoarray,while the etch of the surface of the silicon nanopore was more serious with the increase of the measurement values of various parameters.We believe that the reason for the above phenomenon is related to the etching reaction mechanism and the material transport during the reaction.Then the relationship between the measured value of each variable parameter and the silicon nano-etching rate is analyzed through experiments,and it is found that the influence of the silver nano-particle diameter,the etchant concentration ratio and the etching liquid temperature on the etching of the silicon nano-hole array has a greater weight.The influence weight of erosion time and light power density is small.Finally,based on the relationship between the variable parameters,the measured value of the parameter is adjusted according to the actual manufacturing situation,and the controllable manufacturing of the silver nanoparticle-assisted chemical etching silicon nanopore array is realized.(3)Design silicon nanohole chip sensors,including blind hole silicon nanohole array etching and silicon nanohole chip current detection liquid pool design,and build a sensor detection system with Faraday shield box,current amplifier,data collector and computer.Carry out the contact characteristic research based on the silicon nanopore array,and obtain that the ?-? curve of the silicon nanopore array has a non-rectified ohmic contact relationship.At the same time,according to the ?-? characteristics of the silicon nanohole array,the detection principle of the PSA sensor based on the silicon nanoarray is discussed,which provides a theoretical basis for the manufacture of the silicon micro-nano structure PSA sensor.