Research On Memristor-based Multilevel Storage Circuit Design And Applications

In the era of information globalization, data as the carrier of information need to be stored up and then forwarded out. With the growth of economy, a variety of electronic devices are used in many industries, so the amount of data that needs to be stored is increasing. Thus, the requirements of storage equipment are getting higher and higher. Because of the size of CMOS being nanometer scale, floating gate devices, in the operating voltage, power consumption, integration technology, reliability and circuit design aspects, are encountering physical and technical bottlenecks, which makes the semiconductor technology facing an unprecedented challenge. Memristor which is called the fourth kinds of circuit elements, has a lot of advantages, such as nonvolatile property, nanometer-scale size, fast switching(<10ns), high write endurance(1015), compatible with CMOS and so on, which brings a new dawn for the development of semiconductor memory technology.In this thesis, the memory mechanism of the TiO2 memristor and the memristor with threshold characteristic are deeply studied. The basic threshold characteristics of the memristor are verified by experiment simulation. Combined with the switching characteristic of the transistor and based on the memristor with threshold characteristic, the multilevel memory structure of 2T2M(two transistors and two memristors) is proposed for the 4 and 8 values memory scheme and the feasibility of the two schemes are analyzed. In order to achieve a higher density storage function, combined with the cross array structure, a multilevel memory cross array based on the multilevel memory structure of 2T2 M is proposed, which can effectively solve the leakage current problem. At the same time, the application of the cross array structure in the two value image storage is discussed. Finally, on the basis of the 8 values storage, the data monitoring and error analysis is analyzed by the method of using the memristance ratio definition state, meanwhile the reliability of it is verified.The study results of this thesis provide experimental basis and theoretical support for the multilevel storage application of the memristor and lay the foundation for the development of multilevel storage based on the memristor.