The three-step wet etching(TSWE)method has been proven to be a promising technique for fabricating silicon nanopores.Despite its potential,one of the bottlenecks of this method is the precise control of the silicon et...The three-step wet etching(TSWE)method has been proven to be a promising technique for fabricating silicon nanopores.Despite its potential,one of the bottlenecks of this method is the precise control of the silicon etching and etch-stop,which results in obtaining a well-defined nanopore size.Herein,we present a novel strategy leveraging electrochemical passivation to achieve accurate control over the silicon etching process.By dynamically controlling the oxide layer growth,rapid and reliable etch-stop was achieved in under 4 s,enabling the controllable fabrication of sub-10 nm silicon nanopores.The thickness of the oxide layer was precisely modulated by adjusting the passivation potential,achieving nanopore size shrinkage with a precision better than 2 nm,which can be further enhanced with more refined potential control.This scalable method significantly enhances the TSWE process,offering an efficient approach for producing small-size silicon nanopores with high precision.Importantly,the precise etching control facilitated by electrochemical passivation holds promise for the cost-effective production of high-density,air-insulated monolithic integrated circuits.展开更多
基金financially supported by The National Key R&D Program(2019YFA0707002)the Beijing Innovation Center for Future ChipsBeijing National Research Center for Information.
文摘The three-step wet etching(TSWE)method has been proven to be a promising technique for fabricating silicon nanopores.Despite its potential,one of the bottlenecks of this method is the precise control of the silicon etching and etch-stop,which results in obtaining a well-defined nanopore size.Herein,we present a novel strategy leveraging electrochemical passivation to achieve accurate control over the silicon etching process.By dynamically controlling the oxide layer growth,rapid and reliable etch-stop was achieved in under 4 s,enabling the controllable fabrication of sub-10 nm silicon nanopores.The thickness of the oxide layer was precisely modulated by adjusting the passivation potential,achieving nanopore size shrinkage with a precision better than 2 nm,which can be further enhanced with more refined potential control.This scalable method significantly enhances the TSWE process,offering an efficient approach for producing small-size silicon nanopores with high precision.Importantly,the precise etching control facilitated by electrochemical passivation holds promise for the cost-effective production of high-density,air-insulated monolithic integrated circuits.
