First Principles Study Of Resistive Random Access Memory Based On Single Layer Phosphorus

In the era of data,the demand for memory is higher and higher,so it is necessary to study new memory.In many new memories,the existence of RRAM is particularly bright.Compared with flash,MRAM and FRAM,RRAM is easier to be miniaturized.Compared with pram,RRAM also has advantages in reading and writing voltage,current and speed.In addition,RRAM uses organic materials to make devices flexible,which also makes RRAM have a great prospect in making wearable devices.It can be seen that RRAM is a very competitive new memory.According to the prediction of Moore’s law,the size of devices will be smaller and smaller,but the existing materials can not reach the conditions of science and technology.Therefore,two-dimensional materials with only a few atomic layer thickness have unique advantages in making miniaturized devices.The common two-dimensional materials are graphene,MoS₂,black phosphorene and so on.At present,the research of graphene has been very in-depth,but the zero band gap characteristics of graphene add a lot of difficulties to scientific research,so it is necessary to study other two-dimensional materials.Black phosphorus has attracted many scientists’attention due to higher hole moving speed and petty band gap.However,because BP is a new two dimensional semiconductor,it is not in-depth,so this work will carry out a very in-depth study of black phosphorus and propose a RRAM device based on black phosphorus resistive layer.In this work,Ti₃C₂/single-layer black phosphorus（BP）/Ti₃C₂ RRAM devices are studied based on first principles theory.Firstly,The mobility of carriers in different directions of black phosphorus is calculated.Compared with serrated direction,armchair direction is better,and the monolayer black phosphorus is more obvious,so the conduction direction of the resistive layer is determined.Then,the size of the model is obtained by surface energy and LDOS,the better surface construction of Ti₃C₂/BP was defined by interface binding energy.Studying the potential distribution of the surface,there is a Schottky barrier at the surface.The size of barrier is obtained by formula.Then,the Ti₃C₂/BP/Ti₃C₂ RRAM device is built based on the working mechanism of interface Schottky barrier.The volt ampere characteristics of the device are studied.It is found that the single layer black phosphorus RRAM is a bipolar switching behavior.The on-off threshold voltage is about 1.5V,the set current is 1.28x10^-7A,the Voltage level is 0.5V,and the on-off ratio is 10⁵.Finally,the RRAM need better to reduce the on-voltage and increase the working current.It is found that doping Mg atoms can achieve the goal.The opening voltage of the device becomes 1V,the driving current is doubled by ten.This study may be of guiding significance and value to the experimental research of manufacturing new two-dimensional materials RRAM.