Study On The Effect Of Vaiable Component Al On HfO₂ Resistance

With the development of science and technology and the progress of the times,the requirement of device size is becoming smaller and smaller.Semiconductor devices are facing tremendous pressure and technical challenges.Although traditional memory such as flash can satisfy non-volatility,its slow response speed and limited number of repeatable erases are not conducive to data processing.In order to break through the size limitation of traditional memory,a new requirement is put forward for the development of revolutionary,efficient and brand-new non-volatile storage technology.Therefore,the semiconductor industry has been trying to find non-volatile memory that can simultaneously meet the advantages of high speed,high density,low power consumption and large storage capacity,and can have a new storage mechanism.New non-volatile memory,such as PCM and RRAM,have attracted more and more researchers to further research.It has great potential to be the leader of memory devices in the future.In the research of resistive memory,by analyzing the resistance transition effect of different material systems,it is found that the resistance transition mechanism of different material systems is essentially different.In this paper,the conductive mechanism of metal conductive filaments and oxygen vacancy conductive filaments is studied,which can provide theoretical reference for improving the micro-characteristics of RRAM and deeply analyzing the resistance mechanism of RRAM.Firstly,based on the first-principles calculation software package VASP,and through Material Studio modeling,HfO2 resistive materials were studied.Secondly,conductive filaments were formed in the resistive materials by doping,and the effects of Al conductive filaments and oxygen vacancy conductive filaments on the performance of RRAM were studied.The results show that:1.Al doped into HfO2 by interval is more stable,and the convergence rate of resistance materials tends to be stable is faster.On this basis,five models of HfO2 with different concentrations are established.The partial wave charge density,critical equipotential surface value and formation energy are obtained by comparing and calculating.It is found that the interval Al(Int-Al)concentration of Al conductive filaments is formed,and the doping causes are analyzed.The effect of lattice structure changes on the formation of A1 conductive filaments in HfO2 can significantly reduce the defect formation energy and help to form perfect conductive channels.2.The relative positions of Int-Al and Vacancy Oxygen(VO)are studied,and the partial charge density,maximum equipotential surface and critical equipiotential surface value and formation energy of the varying component Al for HfO2 system with VO defect under the optimum doping mode are calculated.The optimum Int-Al concentration for forming oxygen vacancy conductive filaments in HfO2 material is obtained,and the lattice structure change caused by doping is analyzed.The effect of the formation of VO conductive filaments in HfO2 were studied.It was found that the change of lattice structure could promote the connection of conductive channels.The above research has certain reference and reference significance for improving the performance of HfO2 based resistive storage materials.