Research On 32Mbits Phase Change Memory Array Process

Recently,Phase change memory attracts great attention due to its ideal memory properties such as read and write speed,power consumption,anti-radiation capability,data retention and so on.Therefore,there has been numerous effort to utilize the Phase Change memory inherent advantages such as non-volatility,high speed,low operation voltage,outstanding endurance and mostly for scalability.Industrialization in the phase change memory applications has been achieved but in China,we are on the way in the theoretical research.The purpose of this paper is to fill the vacancy of large-capacity phase-change memory arrays in China,so 32 Mbits phase-change storage arrays were designed and researched.The unit structure and the overall array structure of the 32 Mbits phase change memory array was designed.According to the advantages and disadvantages of several common phase change memory cell structures,the 5 layers phase change unit with characteristic size of 2um was chosen as the basic structure of the array element.At the same time,the overall structure of the array was designed by using the crossbar structure with the smallest array area,and the use of L-edit software design of the layers of the material mask map.By analyzing and comparing the advantages and disadvantages of several common IC manufacturing processes,32 Mbits phase change storage arrays were prepared by contact exposure lithography-magnetron sputtering-Lift-off.By doing some research on the properties of AZ5214 inversion photoresist,find the ideal photolithography parameters in the preparation process.At the same time,the corresponding solutions are put forward for the problems encountered in the preparation of 32 Mbits phase change memory arrays.The Agilent B1500 A semiconductor device analyzer was used to test the memory cells in 32 Mbits phase change memory array.Then select representative data to show the conclusion that most of cells in 32 Mbits phase change memory array can realizehigh resistance to low resistance phase change using DC scaning.