Modulation Of GeBi Thin Film On Magnetic Thin Film And Its Related Research

The rise and development of spintronics provides a theoretical basis and direction for the further development of integrated circuits in the post-Moore era.The in-depth study of spin-related effects and transport mechanisms is inseparable from the discovery and vigorous development of material systems.With the maturity of micro-nano processing technology,the preparation and improvement of magnetic films have made great progress,making it possible to design and manufacture new devices,especially for the innovation of device structures in SOT-MRAM memory cells.CoFeB films have attracted a lot of research due to their higher spin polarizability than ordinary ferromagnetic metals Fe and Co,and large tunneling magneto-resistance of the prepared magnetic tunnel junction.In addition,magnetic insulator films have also gradually become a research hotspot due to their low damping,low power consumption and other characteristics.In order to meet different application requirements,the properties of magnetic thin films need to be modulated and optimized.Under such circumstances,this thesis mainly studies the modulation of GeBi thin film on the magnetic properties of magnetic film CoFeB and Bi:Tm IG,and hopes to construct a magnetic memory unit with Bi:Tm IG film,so a heavy metal/magnetic insulator spin heterojunction is prepared and its anomalous Hall effect is studied.In order to further practical,its read-write circuit is designed and simulated.The main work of this thesis are as follows:In order to obtain GeBi films with excellent properties for follow-up research,semiconductor GeBi films with different Bi content were prepared by molecular beam epitaxy,and the related parameters were measured and analyzed.The Bi content of the prepared GeBi film was 2.76%?19.38%,and the carrier concentration was in the order of10¹⁵cm^-3magnitude.Si/GeBi(x)/CoFeB film structure was prepared,in order to study the influence of the semiconductor material GeBi film with strong spin coupling effect on the magnetic properties of CoFeB film,and the results show that with the increase of GeBi film thickness,the coercivity of CoFeB film had greater modulation,in order to verify that the modulation is due to the magnetic coupling of Bi in the GeBi film,a Cu isolation layer was inserted,and Si/GeBi(x)/Cu(3 nm)/CoFeB structures were prepared for comparative experiments,and in the presence of the Cu layer,there was no significant change in the magnetic properties of the overall structure of the film.Finally,ferromagnetic resonance tests were carried out for different structures.The GGG/Bi:Tm IG/GeBi structure was prepared,and the influence of the presence of GeBi thin films on the magneto-optical properties of the overall structure was tested.In order to study the use of Bi:Tm IG thin films as magnetic storage materials,Bi:Tm IG/Pt heterojunction was prepared by photolithography and etching process,and its anomalous Hall effect was studied,and an attempt was made to enhance the anomalous Hall effect by doping GeBi with Pt..Finally,based on the characteristics of Bi:Tm IG/Pt heterojunction,the modeling of the magnetic memory cell is carried out,and the simulation design of the basic read-write circuit is carried out,which provides a basis for further practical application.