Fabrication And Application Of CMOS-compatible Self-aligned Nanostructure Array

Nanostructure is a key part of the fabraction and development of transistors,sensors,photodetectors and silicon-based batteries,especially in the emerging flexible sensors.The shape and size of nanostructures have a significant impact on the characteristics of nanodevices.It is widely used because of large specific surface areas;high sensitivity and is compatible with CMOS;easy to produce on a large scale in onedimensional silicon nanostructures.Aiming at the challenges faced by the methods of fabrication of nanostructured arrays,the arrays of nanomesh and nanopillar with high efficiency and low cost were been successfully fabracated through two self-aligned spacer image transfer(TSIT)methods and advanced etching processes for the first time.The main work is as follows:(1)Design and fabrication of the arrays of self-aligned nanostructures by two selfaligned spacer image transfer technology.Two layers of crossbar and steep silicon nitride spacer arrays in different directions were been form by TSIT technology,and through different etching methods were used to obtain a pitch of silicon nanostructure arrays is 3μm.The width of the silicon nanomesh array and the diameter of the silicon nanopillar array are about 40 nm.The array has good morphology and the size of the nanomesh and nanopillar arrays formed by these techniques in different directions demonstrate wafer-scale uniformity and high-efficiency;(2)Optimization of self-aligned nanostructured arrays.The arrays of Si nanomesh with different angles(namely:30 °,45 °,60 °)and nanostructure arrays with small pitch(the minimum of pich is 200 nm)have been fabricated in different directions by TSIT,respectively.This demonstrating the good applicability of the TSIT technique for the formation of Si nanomesh and nanopillar arrays in small pitch condition.Furthermore,by adjusting the film deposition and etching conditions,sub-10 nm thin nanopillar arrays are achieved through the TSIT,exceeding the capability of most advanced extreme ultraviolet lithography(EUVL)with a size limit of 16 nm for hole.(3)Fabracation of infrared photodetectors based on the arrays of silicon nanopillar.By spin coating the infrared photoelectric material of Cd Se/Zn S on the array of silicon nanopillar,the MSM of infrared photodetector based on the array of silicon nanopillar has been successfully developed and the infrared photodetector has a wide range of absorption spectrum.In summary,the proposed TSIT technique provides a significant breakthrough in the fabrication of large scale,high uniformity and readily tunable nanostructures for the application of emerging nanotechnology and devices.