Magnetic properties and resistive switching in mixture films and nanolaminates consisting of iron and silicon oxides grown by atomic layer deposition

Abstract

SiO2-Fe2O3 mixture films and nanolaminates were grown by atomic layer deposition from iron trichloride, hexakis(ethylamino)disilane, and ozone at 300 o C. Orthorhombic ε-Fe2O3 was identified in Fe2O3 reference films, and in Fe2O3 layers grown to certain thicknesses between amorphous SiO2 layers. SiO2-Fe2O3 films could be magnetized in external fields, exhibiting saturation and hysteresis in nonlinear magnetization-field curves. Electrical resistive switching, markedly dependent on the ratio of the component oxides, was also observed in films with proper composition. For relatively conductive films, application of small signal measurements allowed one to record memory maps with notable squareness and defined distinction between high and low conductance states.

Swift heavy ion irradiation-induced amorphous iron and Fe–Si oxide phases in metallic 57Fe layer vacuum deposited on surface of SiO2/Si

“…More importantly, the ZFC and FC curves bifurcated from each other, at temperature T irr . T B and T irr depended on the magnetic field applied during the magnetization measurements [57,58]. Thus, the temperature dependence of the FC and ZFC magnetization indicated irreversible behavior between the FC and ZFC data, with the irreversibility depending on the applied magnetic field.…”

High‐Quality Magnetically Hard ε‐Fe2O3 Thin Films through Atomic Layer Deposition for Room‐Temperature Applications

“…Furthermore, excitingly, it has already been demonstrated that the ALD-grown ε-Fe 2 O 3 layers can be straightforwardly implemented in various multilayer structures, e.g., in combination with other ALD-grown inorganic layers (BiOCl and SiO 2 ) or molecular layer deposition (MLD) [45] grown organic layers (benzene or azobenzene) to achieve additional functionalities without compromising the intrinsic magnetic characteristics of the ε-Fe 2 O 3 layers. [23,[46][47][48][49][50] Previously, ALD has also been used for the fabrication of other magnetic iron-oxide thin films, such as Fe 3 O 4 [51,52] and BiFeO 3 , [53,54] but compared to ε-Fe 2 O 3 these materials are notably softer ferromagnets with RT coercivity values well below 1 kOe. On the other hand, inverse-spinel structured (Fe,Co) 3 O 4 films with similar RT coercivity values as those achieved for ε-Fe 2 O 3 films have been fabricated with ALD, but only through more severe conditions, i.e., plasma-enhanced ALD plus subsequent postannealing or ozone-based ALD.…”

“…Furthermore, excitingly, it has already been demonstrated that the ALD‐grown ε‐Fe 2 O 3 layers can be straightforwardly implemented in various multilayer structures, e.g., in combination with other ALD‐grown inorganic layers (BiOCl and SiO 2 ) or molecular layer deposition (MLD) [ 45 ] grown organic layers (benzene or azobenzene) to achieve additional functionalities without compromising the intrinsic magnetic characteristics of the ε‐Fe 2 O 3 layers. [ 23,46–50 ]…”

A Facile Hydrothermal Synthesis and Resistive Switching Behavior of α-Fe2O3 Nanowire Arrays

“…In the last decade, various organic and inorganic nanomaterials have been used for ReRAM applications owing to their unique physical and chemical features [2]. Among them, the transition metal oxide nanomaterials, including Fe 2 O 3 [3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21], ZnO [22], TiO 2 [23], HfO 2 [24], GaO x [25], Co 3 O 4 [26], CuO [27], WO x [28], NiO [29], In 2 O 3 [30], TaO x [31], and CeO 2 [32] have received wide attention because of their facile fabrication process, good compatibility, simple composition as well as excellent resistive switching properties. In recent decades, increasing interest has been devoted to the hematite α-Fe 2 O 3 nanomaterials due to their advantages in terms of the high chemical stability, nontoxicity, low cost, and appropriate band gap [33][34][35] (2.2 eV).…”