Research On Modeling Of 3D Phase Change Memory And Design Of Peripheral Circuit

Memory chips are an important direction in the chip industry that my country needs to develop urgently.As a representative of the next generation of new memory,three-dimensional phase change memory is very likely to become a booster for my country to overtake in the field of memory chips.Compared with the traditional planar two-dimensional phase change memory,the three-dimensional phase change memory is quite different in terms of storage media and peripheral circuits.Since the three-dimensional phase change memory is in the crossbar array that is interleaved horizontally and vertically,the leakage current is a very important issue.The OTS strobe tube is very suitable as a three-dimensional phase change memory in terms of compatibility and device characteristics.It is a strobe device adapted to PCM,so the device based on the 1S1 R structure of PCM+OTS structure can basically be used as a storage unit in the three-dimensional phase change memory.The research of OTS should also have the same importance as PCM.When the PCM and OTS are connected in series in the circuit,due to the large resistance difference between the two,it is easy to oscillate due to the switching behavior of the OTS when voltage is applied.Therefore,the impedance matching problem needs to be considered.This problem is briefly analyzed in this article.At the same time,the differences between the circuit design of the three-dimensional phase change memory and the planar two-dimensional phase change memory and the requirements to be met are analyzed.At the same time,some other array models and device-related issues are also analyzed.In addition,because it takes a lot of time and money to prepare the device,the device and behavior-level modeling of PCM and OTS through device modeling software and circuit simulation software can quickly their internal physical mechanism and circuit Analyze the performance in this article.This article uses Sentaurus TCAD software and HSpice software to perform compact modeling of PCM and OTS at the device level and behavior level,and test DC and pulse accordingly.Some simulation results can be used to design the circuit.Give some guidance.Finally,we used Cadence Virtuoso software and Modelsim software to design the analog module and digital module of the peripheral circuit of the three-dimensional phase change memory.The analog module includes a band gap reference circuit,a charge pump circuit,a hysteresis comparator circuit,and some control circuits.To provide the power supply voltage and realize the read and write functions for the storage unit.In the simulation results,the high-impedance hysteresis comparator outputs 59?V with a delay of 4ns;when reading low-impedance,it outputs a voltage of 3.29 V with a delay of 5ns.In terms of write pulses,the circuit can generate a set pulse of 3.96V/200 ns and a read of 4.77V/50 ns Pulse,the delay is 2ns and 1.1ns respectively,can basically realize the read and write function.The digital module includes seven modules for generating read and write timings of the storage unit and communication between the external host and the storage chip.