Nb-Sb-Te/C稳定多阻态存算一体器件单元的探索研究

类脑神经形态计算器件被认为是突破传统冯诺依曼计算机体系架构瓶颈的关键。相变存储器PCRAM可以精确模拟大脑突触可塑性行为，极具潜力成为类脑神经形态计算系统中的基本突触单元的核心器件。然而PCRAM的部分非晶态在反复操作过程中电阻值波动较大且其功耗较高，不能满足未来高精度、高效率神经元计算器件的要求。针对这个问题，申请人提出构建基于Nb-Sb-Te/C超晶格结构的PCRAM，探索实现对一系列部分非晶态电阻漂移的抑制与器件功耗的降低。项目将在Nb-Sb-Te相变材料中有序的插入C纳米层构建Nb-Sb-Te/C超晶格结构相变薄膜，一方面希望通过Nb掺杂改善Sb2Te3的相变性能，另一方面利用C纳米层实现抑制原子漂移、降低热损耗，最终达到降低器件的电阻漂移与抑制功耗的目的，并深入研究其中的物理本质。本项目的研究具有较高的理论与实用价值，并可以为未来存算一体器件单元的实现提供一定的科学指引。

Neuromorphic computing devices are considered to be the key to break through the bottleneck of traditional Von Neumann computer architecture. Phase change memory (PCRAM) can act as a basic synaptic unit in neuromorphic computing systems, which can accurately simulate synaptic plasticity in the brain. However, PCRAM is unable to meet the requirements of high-precision and high-efficiency neuron computing devices in the future due to its high resistance drift in partial amorphous state and power consumption during repeated operations. In view of the existing problems of PCRAM, the applicant proposed to construct the PCRAM based on Nb-Sb-Te /C heterojunction structure material, hoping to realize the suppression of resistance drift and the reduction of device power consumption. In previous studies, the applicant has found that Nb doped Sb2Te3 can effectively improve the thermal stability and phase transition temperature of the phase change film. Nb doping is expected could improve the phase transition temperature, phase change speed, thermal stability, crystal resistance and other phase transition properties of Sb2Te3. We further use of C nanometer layer to inhibit atomic drift and reduce heat loss, and finally achieve the purpose of reducing the resistance drift and suppression power consumption of the device. In addition, we also aim to clarify the physical mechanism during the phase change in the heterojunction film. The research of this subject has a high theoretical value. From the practical point of view, it can provide the early research results for the future computing in memory device unit.