Preparation,Nucleation Mechanism And Photoelectric Properties Control Of P-Type Porous Silicon

Porous silicon as a novel material derived from single crystal silicon not only has good semiconductor characteristics,but also has many excellent characteristics such as low cost,high uniformity,high aspect ratio,large specific surface area.This material has been widely used in MEMS,energy storage,biosensing and other fields.At present,the preparation technology of N-type porous silicon has been basically mature,and the research on the pore-forming mechanism of P-type porous silicon is still in the exploration stage,which greatly limits the further application of porous silicon.In this paper,theoretical and experimental systematic studies on the growth process,nucleation evolution and multilayer structure of P-type porous silicon are carried out.The effects of different corrosion conditions on the nucleation process,pore-forming structure and optical properties of porous silicon were revealed,and the optical properties and electrical properties of porous silicon were studied.The main research contents and innovations are as follows:Firstly,the nucleation process of P-type porous silicon was experimentally studied,and the growth model of P-type porous silicon was improved.It was revealed that in the P-type porous silicon nucleation process,different corrosion conditions such as current density,HF concentration and electrolyte composition were observed.The effects of nucleation speed and nucleation depth.The results show that increasing the current density and HF acid concentration can effectively increase the nucleation rate of porous silicon,which provides a theoretical basis for the rapid preparation of porous silicon.Secondly,the micro-nanopore structure and its optical properties control during the growth of P-type porous silicon were systematically studied.The results show that the use of strong oxidants and organic solvents can effectively broaden the current window of porous silicon on low-resistance silicon substrates.At the same time,the modification of the electrolyte can realize the preparation and preparation of the porous silicon microstructure,which not only enhances the photoluminescence property of the porous silicon but also improves its response to ultraviolet light.This study laid the foundation for the development of porous silicon-based optics.Finally,porous silicon/zinc oxide composites were prepared to optimize the electrical properties of porous silicon.The results show that nano-zinc oxide can passivate the surface of porous silicon and greatly improve the capacitance characteristics of porous silicon.It still has good stability after 500 cycles of voltammetry,and is developed for a new porous silicon-based supercapacitor.Provides a theoretical basis.This paper systematically studies the nucleation mechanism,growth model,microstructure control and porous silicon surface passivation of P-type porous silicon.It provides a theoretical basis for the rapid preparation of porous silicon and its application in optoelectronic devices and supercapacitors.