Study On Modification Of Si-Sb Based Phase Change Memory Materials

Phase change storage technology is closely linked to people's daily work and life,and it has become an indispensable part.Phase change memory is considered to be the next generation of mainstream non-volatile storage products due to its high density,fast storage,multicycle erasing,strong anti-interference ability,compatibility with semiconductor manufacturing processes,and easy portability.Phase change memory material,as the core part of phase change memory,is the focus of research.Currently,Ge₂Sb₂Te₅,a relatively mature material,is a chalcogenide memory material.The existence of chalcogens makes the amorphous and crystalline electrical properties of the materials significantly different,the film resistance differs by 5 orders of magnitude,and the maximum number of reversible cycles can reach 10¹⁷ times.Similarly,the presence of chalcogens can easily lead to the instability of the phase change material itself and the displacement of the heating electrode components,which affects the reliability of the device.Chalcogens are used in the consumer electronics industry,and the harm to humans and the environment still needs to be resolved.In view of the above analysis,this article has studied the Te-free Si-Sb based phase change storage material,with the aim of researching a environmentally friendly and high performance phase change storage media.In this paper,a variety of Si-Sb based phase-change memory thin film materials are prepared by multi-target co-sputtering by magnetron sputtering,like Si_xSb_100-x,Sn_x(Si₁₆Sb₈₄)_100-x,Ge_x(Si₁₉Sb₈₁)_100-x.X-ray energy spectrometer,X-ray diffractometer,atomic force microscope and ultraviolet spectrophotometer are used to characterize the physical and chemical properties of materials.The self-built in-situ vacuum four-probe resistance measuring device is used to measure the resistance temperature characteristic curve of the thin film material.Arrhenius and Kissinger formulas are used to fit the relevant performance.The experimental results show that:The increase of Si content in Si_xSb_100-x binary phase change storage material is beneficial to increase the crystallization temperature of thin film materials When the Si content is 19%,the crystallization temperature reaches 203?.The thermal stability of the Si_xSb_100-x series phase change memory materials is significantly better than that of Ge₂Sb₂Te₅ materials,but the crystallization mechanism of the two materials is the same,both of which are nucleated crystals.The results of particle size statistics show that,in the crystalline state,the grain size of the Si₁₆Sb₈₄ thin film material is less than 20nm,and the annealing heat treatment is beneficial to the grain growth.The crystallization temperature of Sn_x(Si₁₆Sb₈₄)_100-x phase change memory film material is the highest when the Sn doping content is 2%,reaching 219?.At this time,the crystallization activation energy of the thin film is 4.390eV,and the ten-year data retention temperature is 144?.The results are all superior to other ingredients.It is worth mentioning that the Sn doping affects the crystallization mode of the thin film material.The Sn_x(Si₁₆Sb₈₄)_100-x phase change memory thin film material is a grain growth type crystal,which is more beneficial to speeding up the phase transition.Comparative analysis shows that when 2%Sn is doped,the film material has excellent performance and has development potential.The crystallization temperature of Ge_x(Si₁₉Sb₈₁)_100-x phase-change memory film material is higher,higher than 200?,and the crystallization temperature increases with the increase of the doping amount of Ge.The optical band gap measurement of the material is3.35eV,which is much higher than the band gap of Ge₂Sb₂Te₅ material,indicating that the material can reduce the threshold current and reduce the power consumption of the device.The grain size of Ge doped thin film materials is large and the change before and after annealing is great.Multiple cycles of heating can easily lead to device cracking and failure.So,the properties of Ge doped thin film materials are not good.