Study On Performance Optimization Of TaO_x Based Resistive Memory With Ru Base Electrode

With the advent of 5G,network interaction will become more frequent,and the amount of data uploading and downloading will be several times that of the previous 4G era.This means that both the server and the cloud need faster and larger storage devices than in the past.New storage technology will become an important topic in the storage industry.As the complementary metal-oxide-semiconductor(CMOS)technology is approaching its size limit,the traditional flash used in the electronic industry has reached its limit in terms of reducing the size.Resistive random access memory(RRAM)has a metal-insulator-metal(MIM)structure,which uses resistance transition behavior to store information and provides a new type of device that can surpass the performance of traditional semiconductor electronic devices.Compared with charge-based memory devices,resistive memory has the advantages of low power consumption,high reliability,excellent switching speed,and compatibility with the CMOS process,showing great potential as a current non-volatile memory.However,there are still some problems such as unstable operation and short life in the practical application of resistive memory,so this paper will study the performance optimization of devices with TaO_x thin film as a resistive layer.In this thesis,a resistive memory with Ta/TaO_x/Ru structure is prepared.Firstly,the TaO_x film with the best performance was obtained by changing the oxygen partial pressure and thickness of the film.The experimental results show that the performance of the device is the best when the process condition of TaO_x film is 10%oxygen partial pressure and 10nm thickness.However,there is still room for improvement in the device performance under this condition.Therefore,the prepared devices were rapidly annealed in a vacuum and oxygen atmosphere(300??120s).Through a series of tests and characterization,it is found that due to the amorphous/nanocrystalline formed by TaO_x after annealing,the conductive filament is uniformly formed,and the stability of the device is improved obviously.In addition,the Ta electrode will act as an oxygen storage layer after annealing in an oxygen atmosphere,and the cycle life of the device is longer and the resistance window is larger.Finally,the flexible polyimide(PI)substrate is selected to fabricate Ta/TaO_x/Ru flexible resistive memory on PI,and the bending test of the device is carried out at different radius.It is verified that the device can also cycle 500 times after bending for 4 mm radius and 500 times after bending for4 mm radius,indicating that the device has good flexibility.To improve the performance of the device,two rapid annealing methods are proposed,and the reasons for performance improvement and resistance mechanism are described in detail through a series of tests and characterizations.It provides a simple and efficient way to improve the performance of oxide resistive memory.