In recent years, phase change memory technology, as a new technology that can change the rules of the game, has gradually become a potential alternative to computer random access memory.The phase change memory chip uses heat to change the phase state of the material from amorphous to crystalline, With its fast speed, low power consumption and small size, it is possible to make smaller and more powerful computing systems possible.However, phase-change memories have been unable to achieve large-scale quantities due to their challenges in quality consistency and durability Production.
Researchers at Yale University and IBM believe that accurate understanding of the phase transition behavior of devices is the key to removing barriers and solving the practicality of phase-change memory, and recently they used in-situ transmitted electrons from the YINQE Institute for Nanoscience and Quantum Engineering The phase change process of phase change memory was observed and researched by microscope, and how to realize the self-repairing of the phase defect of the phase change material was discovered and a new self-healing sealed phase change memory was successfully developed. Published in the top journal "Advanced Materials." A hollow defect in PCMs is the nanoscale defect space left by material loss due to chemical separation, which is the culprit of the practicality of PCMs.
The standard phase-change memory has a mushroom-like umbrella structure, and the Yale-IBM research team changed the new phase-change memory structure to an enclosed inverted-cone structure surrounded by a metal layer to enhance the stability and durability of the device. The metal layer protects the phase change material and can drift the resistance of the smaller phase change memory to improve the overall performance of the device.
By observing the phase transition through TEM, the researchers saw the effect of self-repairing the phase change memory after changing the device structure and adding the metal outer liner, which made the phase transition process of the GST material more Controllable.
The researchers revealed that the next step will be to develop a bipolar mode of operation to change the direction of the voltage to control the chemical separation process. Under normal operating mode, the direction of the device voltage bias is always the same. Implementation is expected to further extend phase-change memory life cycle.