magnetic storage device

Abstract

A magnetic memory device comprising: a first vertical magnetic layer (123) having a first vertical magnetization direction; a non-magnetic layer (130) on the first vertical magnetic layer (123); a first magnetic transition layer (141) on the non-magnetic layer (130), the non-magnetic layer (130) being located between the first vertical magnetic layer (123) and the first magnetic transition layer (141); a tunnel barrier (145) on the first magnetic transition layer (141), the first magnetic transition layer (141) being located between the non-magnetic layer (130) and the tunnel barrier (145); a second magnetic transition layer (149) on the tunnel barrier (145), the tunnel barrier (145) being located between the first (141) and the second magnetic transition layer (149);anda second vertical magnetic layer (163) having a second vertical magnetization direction on the second magnetic transition layer (149),wherein the second magnetic transition layer (149) lies between the tunnel barrier (145) and the second vertical magnetic layer (163),wherein the first and second vertical magnetization directions are perpendicular with respect to a plane of the tunnel barrier (145), andwherein an iron content in the second magnetic transition layer (149) is greater than that in the first magnetic transition layer (141).;

Description

BACKGROUNDThe disclosure herein relates to memory devices, and more particularly to magnetic memory devices.Further, since high access speeds and low power consumption have been realized in electronic devices, memory devices may require fast read / write performance and low operating voltages. As memory devices, magnetic memory devices are being studied to provide increased speed and reduced operating voltage. Since magnetic storage devices can provide high access speeds and / or nonvolatile characteristics, they have attracted attention to the next generation of data storage.Commonly known magnetic storage devices may include a magnetic tunnel junction (MTJ) pattern. The tunnel magnetic contact pattern is formed by two magnetic substances and an insulating layer interposed therebetween, and the resistance value of the tunnel magnetic contact pattern can be varied according to the magnetization direction of the two magnetic substances. In particular, when the magnetization directions of the two magnetic substances are anti-parallel to each other, the magnetic tunnel junction pattern may have a high resistance value. When the magnetization directions of the two magnetic substances are parallel to each other, the magnetic tunnel contact pattern may have a low resistance value. The difference between these resistance values can be used for writing / reading data.The document US 2009 / 0 080 238 A1 discloses a low-resistance magnetoresistive element of the spin injection writing type. A crystallization promoting layer promoting crystallization is formed in contact with a magnetic barrier layer having an amorphous structure, so that the crystallization is promoted from a tunnel barrier layer side and the interface between the tunnel barrier layer and the magnetic barrier layer is matched.SummaryIt is an object of the present invention to enable a magnetic storage device with increased reliability, a high magnetic resistance ratio and / or reduced operating performance.The object is achieved by the magnetic storage device according to claim 1. Further developments of the magnetic storage device according to the invention are the subject matter of the dependent claims.In a magnetic memory device according to the present invention, by interposing a non-magnetic layer between a vertical magnetic layer and a magnetic junction layer, a magnetic resistance ratio and a vertical magnetization characteristic of a magnetic tunnel junction including the magnetic junction layer can be improved. In addition, during the operation of the magnetic storage device, switching characteristics can be improved by a free magnetic layer and a reference magnetic layer each having a different content of iron. Accordingly, the reliability of the magnetic storage device can be improved.Brief Description of the FiguresThe appended figures are incorporated in this specification for a better understanding of the inventive concept. The figures represent exemplary embodiments of the inventive concept and together with the description serve to explain the concept of the inventive concept. The figures show: FIG. 1 is a view illustrating a magnetic memory device according to the first embodiments of the inventive concept; FIG. 2 is a view illustrating a modified example of a magnetic memory device according to the first embodiments of the inventive concept; FIG. 3 is a view illustrating another modified example of a magnetic memory device according to the first embodiments of the inventive concept; FIGS. 4A to 4C are views describing a method for a magnetic memory device according to the first embodiments of the inventive concept; FIG. 5 is a view illustrating a magnetic memory device according to the second embodiments of the inventive concept; FIG. 6 is a view illustrating a modified example of a magnetic memory device according to the second embodiments of the inventive concept; FIG. 7 is a view illustrating a magnetic memory device of the inventive concept; FIG. 8 is a view describing a method for a magnetic memory device according to the third embodiments of the inventive concept; FIG. 9 is a view describing a crystal structure according to the third embodiments of the inventive concept; FIG. 10 is a view illustrating a magnetic memory device according to the fourth embodiments of the inventive concept.Detailed Description of EmbodimentsMagnetic memory devices and methods for forming the same according to the embodiments of the inventive concept will be described in more detail below with reference to the accompanying drawings. Described embodiments are provided so that the concept of the inventive concept can be easily understood by those skilled in the art, and the inventive concept should not be construed as being limited thereto. Embodiments of the inventive concept may be embodied in various forms that fall within the technical spirit and scope of the inventive concept. In the figures, the thicknesses and relative thicknesses of elements may be exaggerated to clearly illustrate embodiments of the inventive concept. Terms associated with the positions, such as upper and lower terms in the specification, are relative terms to make the description clear and should not be construed as limiting the positions between the absolute elements.It is understood that an element is referred to as being "connected to" or "coupled to" another element if it may be directly connected or coupled to / on the other element or intervening elements may be present. In contrast, when an element is referred to as being "directly connected to" or "directly coupled to" another element, there are no intervening elements present. As used herein, the term "and / or" includes any and all combinations of one or more associated listed terms.It will be understood that although the terms first, second, etc. may be used to describe various elements, components, regions, layers, and / or sections, these elements, components, regions, layers, and / or sections are not intended to be limited to these terms. These terms are used only to distinguish one element, component, region, layer, or portion from another region, layer, or portion. Thus, a first element, component, region, layer, or portion discussed below could be referred to as a second element, component, region, layer, or portion without departing from the teachings of the inventive concept.Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as understood by one of ordinary skill in the art to which the inventive concept pertains. It will be further understood that terms used herein are to be interpreted as having a meaning that is consistent with a meaning in the context of this specification and the related art, and are not to be interpreted in an idealized or overformal manner unless expressly so defined herein.In addition, when terms used in this specification are not specifically defined, all terms (including technical and scientific terms) used in this specification can be understood as would be understood by a person skilled in the art. Further, when general terms defined in the dictionaries are not particularly defined, these terms have the usual meaning in the art.Relative terms such as "below" or "above" or "upper" or "lower" or "horizontal" or "lateral" or "perpendicular" may be used herein to describe a relationship of one element, layer or region with another element, layer or region as depicted in the figures. It will be understood that these terms are intended to encompass different orientations of the device in addition to the orientation depicted in the figures.The language used herein is for the purpose of describing particular embodiments only and is not intended to limit example embodiments. As used herein, the singular forms "a / an / an" and "the / s" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will also be understood that the terms "comprise" and / or "comprising," when used herein, specify the presence of stated features integers, steps, operations, elements, layers, and / or components, but do not preclude the presence or addition of one or more other features integers, steps, operations, elements, layers, components, and / or groups thereof.In the figures, the features illustrated may be altered due to, e.g., manufacturing technology and / or tolerance. Accordingly, it should be understood that exemplary embodiments of the inventive concept are not limited to figures, but include modifications of the features of elements caused due to, e.g., manufacturing tolerances.(A First Embodiment and Modified Examples thereof)Referring to FIG. 1, a magnetic memory device according to the first embodiments of the inventive concept will be described. A lower electrode 110 is disposed on a substrate 100. The substrate 100 may be a semiconductor-based semiconductor substrate. The substrate 100 may include a conductive region and / or an insulating region. The lower electrode 110 may be electrically connected to the conductive portion of the substrate 100. The lower electrode 110 may be disposed on the substrate 100 and / or in the substrate 100. For example, the bottom electrode 110 may have any shape selected from the group consisting of a line, island, and / or plate.A first vertical magnetic layer 123 may be disposed on the lower electrode 110. In an embodiment, the first vertical magnetic layer 123 may include alternately stacked non-magnetic layers 121 and ferromagnetic layers 122. The ferromagnetic layers 122 may include at least one selected from the group consisting of iron (Fe), cobalt (Co), and / or nickel (Ni), and the non-magnetic layers 121 may include at least one selected from the group consisting of chromium (Cr), platinum (Pt), palladium (Pd), iridium (Ir), ruthenium (Ru), rhodium (Rh), osmium (Os), rhenium (Re), gold (Au), and / or copper (Cu). The first vertical magnetic layer 123 may be, for example, a magnetic layer having a vertical direction. [Co / Pt]m, [Co / Pd]m, [Ni / Pt]m (m is a stack number of each layer and a natural number of two or more), or a combination thereof. In an embodiment, the non-magnetic layers 121 and ferromagnetic layers 122, respectively, may be stacked in a range of about 2 to about 20 times. When the current flows in a direction vertical (perpendicular) to the substrate 100 and the planes of the first vertical magnetic layers 123, the first vertical magnetic layer 123 may be formed to have a magnetization direction parallel to the current. For this configuration, the ferromagnetic layers 122 may be formed thin with a thickness of one or more atomic layers.A first non-magnetic layer 130 may be disposed on the first vertical magnetic layer 123. The first non-magnetic layer 130 may have a relatively small thickness. For example, the first non-magnetic layer 130 may be formed with a thickness in a range from about 0.2 nm (nanometers) to about 2.0 nm (nanometers). This first non-magnetic layer 130 may not have a texture. For example, the first non-magnetic layer 130 may be uniformly formed on the first vertical magnetic layer 123, and may not have a texture due to the small thickness.The first nonmagnetic layer 130 may include at least one selected from nonmagnetic metal elements having nonmagnetic transition metal. For example, the first non-magnetic layer 130 may include at least one selected from the group consisting of magnesium (Mg), aluminum (Al), titanium (Ti), chromium (Cr), ruthenium (Ru), copper (Cu), zinc (Zn), tantalum (Ta), gold (Au), silver (Ag), palladium (Pd), rhodium (Rh), iridium (Ir), molybdenum (Mo), vanadium (V), tungsten (W), niobium (Nb), zirconium (Zr), yttrium (Y), and / or hafnium (Hf).In an embodiment, the first non-magnetic layer may be formed with a plurality of layers. For example, the non-magnetic layer 130 may include a first lower metal compound layer 133, a first non-magnetic metal layer 136, and a first upper metal compound layer 139, which are sequentially stacked on the vertical magnetic layer 123. Although not shown in FIG. 1, the first nonmagnetic layer 130 may include a metal compound layer / nonmagnetic metal layer and / or a nonmagnetic metal layer / metal compound layer, which are sequentially stacked on the vertical magnetic layer 123. The first non-magnetic metal layer 136 may include at least one selected from the group consisting of magnesium (Mg), aluminum (Al), titanium (Ti), chromium (Cr), ruthenium (Ru), copper (Cu), zinc (Zn), tantalum (Ta), gold (Au), silver (Ag), palladium (Pd), rhodium (Rh), iridium (Ir), molybdenum (Mo), vanadium (V), tungsten (W), niobium (Nb), zirconium (Zr), yttrium (Y), and / or hafnium (Hf). The first lower and upper metal compound layers 133, 139 may be a metal oxide, a metal nitride, a metal oxynitride, and / or a combination thereof. For example, each metal connection layer may be, for example, a connection of the metal layers. Conversely, the first non-magnetic layer 130 may include only a single metal layer or a plurality of metal layers. Diffusion of metal atoms in the first non-magnetic metal layer 136 into another adjacent layer may be prevented and / or reduced by the first lower and upper metal compound layers 133, 139.A first magnetic transition layer 141 may be disposed on the first non-magnetic layer 130. The first magnetic transition layer 141 may include a soft magnetic material. The first transition layer 141 may have a low attenuation constant and a high spin polarization ratio. For example, the first magnetic transition layer 141 may include at least one selected from the group consisting of cobalt (Cu), iron (Fe), and / or nickel (Ni). The first magnetic transition layer 141 may further include at least one selected from non-magnetic materials including boron (B), zinc (Zn), aluminum (Al), titanium (Ti), ruthenium (Ru), tantalum (Ta), silicon (Si), silver (Ag), gold (Au), copper (Cu), carbon (C), and / or nitrogen (N). Specifically, the first magnetic transition layer may include CoFe and / or NiFe, and may further include boron (B). Moreover, in order to reduce a saturation magnetization of the first magnetic junction layer 141, the first magnetic junction layer 141 may further include at least one selected from the group consisting of titanium (Ti), aluminum (Al), silicon (Si), magnesium (Mg), tantalum (Ta), and / or silicon Si).The first non-magnetic layer 130 between the first transition magnetic layer 141 and the first vertical magnetic layer 123 may increase the vertical magnetic anisotropy of a magnetic storage cell including the same. For example, the first magnetic transition layer 141 may be antiferromagnetically or ferromagnetically exchange-coupled to the first vertical magnetic layer 123 through the first nonmagnetic layer 130. Since the first vertical magnetic layer 123 has high vertical magnetic anisotropy, the vertical magnetic anisotropy of the first magnetic transition layer 141 exchange-coupled to the first vertical magnetic layer 123 may also be increased. The vertical magnetic anisotropy in the description is defined as a property of the layer to be magnetized in the direction vertical to the plane of the substrate 100. As used herein, the term vertical may refer to a direction that is perpendicular to a surface of the substrate 100.The crystal structure of the first transition magnetic layer 141 may be different from that of the first vertical magnetic layer 123 due to the first non-magnetic layer 130. Accordingly, the magnetic resistance ratio of a magnetic tunnel junction can be further increased. A detailed description thereof is provided with respect to the methods of forming a first transition metal layer 141, which will be described below.A tunnel barrier 145 may be disposed on the first transition metal layer 145. The tunnel barrier 145 may have a thickness less than the spin diffusion length. The tunnel barrier 145 may include a non-magnetic material. In an embodiment, the tunnel barrier 145 may be formed of an insulating material layer. Conversely, the tunnel barrier 145 may include a plurality of layers. For example, the tunnel barrier 145 may include at least one selected from the group consisting of magnesium (Mg), titanium (Ti), aluminum (Al), an oxide of magnesium zinc (MgZn), and / or magnesium boron (MgB), and / or a nitride of titanium (Ti) and / or vanadium (V). For example, the tunnel barrier may be formed of a magnesium oxide (MgO) layer.The tunnel barrier 145 may have a crystal structure similar to that of the first magnetic transition layer 141. For example, the first magnetic transition layer 141 may include a magnetic material having a body centered cubic (krz) structure or may include a magnetic material having a body centered cubic structure including a non-magnetic element. When the first magnetic transition layer 141 includes a non-magnetic element, the magnetic material may become amorphous. The tunnel barrier 145 and the first magnetic transition layer 141 may each have a NaCl type crystal structure and a body centered cubic structure, and the (001) crystal plane of the tunnel barrier 145 may contact the (001) crystal plane of the first magnetic transition layer 141 to form an interface. The magnetoresistance ratio of a magnetic tunnel junction including the tunnel barrier 145 and the first magnetic junction layer 141 can be thereby increased.A second magnetic transition layer 149 may be disposed on the tunnel barrier. The second magnetic transition layer 149 may include a soft magnetic material. For example, the second magnetic transition layer 149 may contain cobalt (Co), iron (Fe), and / or nickel (Ni) atoms, so that the content of the atoms can be determined to reduce the saturation magnetization of the second magnetic transition layer 149. The second magnetic transition layer 149 may have a low attenuation constant and a high spin polarization ratio. To achieve this, the second magnetic transition layer 149 may further include at least one selected from non-magnetic materials including boron (B), zinc (Zn), aluminum (Al), titanium (Ti), ruthenium (Ru), tantalum (Ta), silicon (Si), silver (Ag), gold (Au), copper (Cu), carbon (C) and / or nitrogen (N). For example, the second magnetic transition layer 149 may include CoFe and / or NiFe, and may further include boron. Moreover, the second magnetic transition layer 149 may include at least one selected from non-magnetic elements including titanium (Ti), aluminum (Al), silicon (Si), magnesium (Mg), and / or tantalum (Ta). The content of the selected non-magnetic element in the second magnetic transition layer 149 may be in a range of about 1% to about 15% atomic percent. When the second magnetic junction layer 149 is used as a free layer of a magnetic memory cell, the saturation magnetization of the second magnetic junction layer 149 can be controlled to be lower than that of the first magnetic junction layer 141.The second magnetic transition layer 149 may have a crystal structure similar to that of the tunnel barrier 145. For example, the tunnel barrier 145 and the second magnetic transition layer 149 may have a NaCl type crystal structure and a body centered cubic structure, and the (001) crystal plane of the tunnel barrier 145 may contact the (001) crystal plane of the second magnetic transition layer 149 to form an interface. The magneto-resistance ratio of a magnetic tunnel junction including the second magnetic junction layer 149 and the tunnel barrier 145 can be increased thereby.In some embodiments, the content of ferromagnetic atoms in the second magnetic transition layer 149 may be different from that of ferromagnetic atoms in the first magnetic transition layer 141. For example, the first and second magnetic transition layers 141, 149 may include at least one selected from cobalt (Co), nickel (Ni), and / or iron (Fe), while the iron (Fe) content in the second magnetic transition layer 149 is equal to or more than that in the first magnetic transition layer 141. In this case, the second magnetic layer 149 may serve as a free layer.A second non-magnetic layer 150 may be disposed on the second magnetic transition layer 149. The second non-magnetic layer 150 may be formed with a relatively small thickness. For example, the second non-magnetic layer 150 may be formed to have a thickness in a range of about 0.2 nm (nanometers) to 2.0 nm (nanometers). The second non-magnetic layer 150 may not have a texture. For example, the second non-magnetic layer 150 may be uniformly formed on the second magnetic connection layer 149 and may not have a texture due to the small thickness.The second nonmagnetic layer 150 may include at least one selected from nonmagnetic metal elements containing a nonmagnetic transition metal. For example, the second non-magnetic layer 150 may include at least one selected from the group consisting of magnesium (Mg), aluminum (Al), titanium (Ti), chromium (Cr), ruthenium (Ru), copper (Cu), zinc (Zn), tantalum (Ta), gold (Au), silver (Ag), palladium (Pd), rhodium (Rh), iridium (Ir), molybdenum (Mo), vanadium (V), tungsten (W), niobium (Nb), zirconium (Zr), yttrium (Y), and / or hafnium (Hf).In some embodiments, the second non-magnetic layer 150 is formed with a plurality of layers. For example, the second non-magnetic layer 150 may include a second lower metal compound layer 153, a second non-magnetic metal layer 156, and a second upper metal compound layer 159, which are sequentially stacked on the second transition magnetic layer 149. Although not shown in FIG. 1, the second non-magnetic layer 150 may include a metal connection layer / non-magnetic metal layer or a non-magnetic metal layer / metal connection layer sequentially stacked on the second magnetic connection layer 149. The second non-magnetic metal layer 156 may include at least one selected from the group consisting of magnesium (Mg), aluminum (Al), titanium (Ti), chromium (Cr), ruthenium (Ru), copper (Cu), zinc (Zn), tantalum (Ta), gold (Au), silver (Ag), palladium (Pd), rhodium (Rh), iridium (Ir), molybdenum (Mo), vanadium (V), tungsten (W), niobium (Nb), zirconium (Zr), yttrium (Y), and / or hafnium (Hf). The second lower and upper metal compound layers 153, 159 may be a metal oxide, a metal nitride, a metal oxynitride, or a combination thereof. For example, the second lower and upper metal connection layers 153, 159 may be formed of a connection of the second non-magnetic metal layer 156. The diffusion of metal atoms in the second non-magnetic metal layer 156 into another adjacent layer may be prevented and / or reduced by the second lower and upper metal compound layers 153, 159. Conversely, the second non-magnetic layer 150 may include only a single metal layer or a plurality of metal layers.A second vertical magnetic layer 163 may be disposed on the second non-magnetic layer 150. In some embodiments, the second vertical magnetic layer 163 may include alternately stacked non-magnetic layers 161 and ferromagnetic layers 162. The ferromagnetic layers 162 may include at least one selected from the group consisting of iron (Fe), cobalt (Co), and / or nickel (Ni), while the non-magnetic layers 161 include at least one selected from the group consisting of chromium (Cr), platinum (Pt), palladium (Pd), iridium (Ir), ruthenium (Ru), rhodium (Rh), osmium (Os), rhenium (Re), gold (Au), and / or silver (Cu). For example, the second vertical magnetic layer 163 may include [Co / Pt]n, [Co / Pd]n, [Ni / Pt]n (n is a stack number of each layer and a natural number of 2 or more), or a combination thereof. The ferromagnetic layers 162 may be formed with a thickness of one to more atoms. The exchange coupling between the second vertical magnetic layer 163 and the second transition magnetic layer 149 may be enhanced by the second non-magnetic layer 150. The vertical magnetic anisotropy of the second magnetic transition layer 149 can thereby be increased.The stack numbers n of non-magnetic layers 161 and ferromagnetic layers 162 in the second vertical magnetic layer 163 may be different from those of the m non-magnetic layers 121 and ferromagnetic layers 122 of the first vertical magnetic layer 123. For example, the stacking number of non-magnetic layers 161 and ferromagnetic layers 162 of the second vertical magnetic layer 163 may be smaller than that of non-magnetic layers 121 and ferromagnetic layers 122 of the first vertical magnetic layer 123. In this case, a first magnetic junction layer 141 adjacent to the first vertical magnetic layer 123 may serve as a reference layer of a magnetic memory cell, while a second magnetic junction layer 149 adjacent to the second vertical magnetic layer 163 serves as a free layer of the magnetic memory cells. Conversely, the stack number n of non-magnetic layers 161 and ferromagnetic layers 162 of the second vertical magnetic layer 163 may be larger than that of the n non-magnetic layers 121 and ferromagnetic layers 122 of the first vertical magnetic layer 123. In this case, the second magnetic transition layer 141 may serve as a reference layer, while the first magnetic transition layer 149 serves as a free layer.The first and second magnetic transition layers 141, 149 may have different magnetic properties according to the functions being performed. For example, the magnetic transition layer serving as the free layer may have a smaller saturation magnetization than that of the magnetic transition layer serving as the reference layer. The saturation magnetization may be controlled by the ratio of a contained ferromagnetic material (Co, Ni and / or Fe) and / or ratio of non-magnetic material.The first magnetic junction layer 141, the tunnel barrier 145, and the second magnetic junction layer 149 may form a magnetic tunnel junction of a magnetic memory cell. Data can be stored in a magnetic memory cell including the magnetic tunnel contacts by using a difference between resistance values of magnetic tunnel contacts whether the magnetization directions of the free layer and the reference layer are parallel or antiparallel to each other. The magnetization direction of the free layer may be varied according to the direction of current supplied to the magnetic memory cell. For example, the magnetization direction of the free layer, in the case where the current is supplied from the first magnetic transition layer 141 to the second magnetic transition layer 149, may be antiparallel, in the case where the current is supplied from the second magnetic transition layer 149 to the first magnetic transition layer 141. The magnetization direction of the reference layer and the free layer may be vertical to the plane of the substrate 100. The reference layer may be vertical to the plane of the substrate 100 and have a fixed first magnetization direction. The free layer has a magnetization direction vertical to the plane of the substrate 100, and the magnetization direction of the free layer may be the first magnetization direction or a second magnetization direction which is antiparallel to the first magnetization according to the direction of the supplied current.A capping layer 170 may be disposed on the second vertical magnetic layer 163. The capping layer 170 may include at least one selected from the group consisting of tantalum (Ta), aluminum (Al), copper (Cu), gold (Au), silver (Ag), titanium (Ti), ruthenium (Ru), magnesium (Mg), tantalum nitride (TaN), and / or titanium nitride (TiN).Referring to FIG. 2, a modified example of a magnetic memory device according to some embodiments of the inventive concept will be described.The description of the same elements, substantially identical to the elements described in FIG. 1, may be omitted for clarity and / or brevity.A lower electrode is disposed on a substrate 100. A seed layer 115 and a first vertical magnetic layer 124 are disposed on the lower electrode 110. The seed layer 115 may contain metal atoms that form a hexagonal close packed (hcp) lattice. The seed layer 115 may be formed to have a thickness that extends from about 1.0 nm (nanometers) to about 10.0 nm (nanometers). The seed layer 115 may include ruthenium (Ru) or titanium (Ti). Conversely, the seed layer 115 may contain metal atoms that form a face centered cubic (kfz) lattice. For example, the seed layer 115 may include platinum (Pt), palladium (Pd), gold (Au), silver (Ag), copper (Cu), and / or aluminum (Al). The seed layer 115 may include a single layer or a plurality of layers having different crystal structures. Conversely, when a material forming the first vertical magnetic layer 124 is amorphous, the seed layer 115 may be omitted.The magnetization direction of the first vertical magnetic layer 124 may be substantially vertical to the plane of the substrate 100 and may be modified. To achieve this, the first vertical magnetic layer 124 may include at least one selected from the group consisting of a material having an L10crystal structure, a material having a hexagonal close-packed (hcp) lattice, and a rare earth transition metal (RE-TM) amorphous alloy. For example, the first vertical magnetic layer 124 may be at least one selected from materials having an L10crystal structure including Fe 50 Pt 50, Fe 50 Pd 50, Co 50 Pt 50, Co 50 Pd 50 and / or Fe 50 Ni 50 Conversely, the first vertical magnetic layer 124 may include a disordered cobalt-platinum alloy having a platinum content of about 10% to about 45% atomic percent or an ordered Co3Pt alloy having a hexagonal close-packed (hcp) lattice. Conversely, the first vertical magnetic layer 124 may include at least one selected from amorphous RE-TM alloys including at least one selected from the group consisting of iron (Fe), cobalt (Co), and / or nickel (Ni), and at least one selected from the group consisting of rare earth terbium (Tb), dysprosium (Dy), and / or gadolinium (Gd).A first non-magnetic layer 130 may be disposed on the first vertical magnetic layer 124. The first non-magnetic layer 130 may be formed with a small thickness. For example, the first non-magnetic layer 130 may be formed to have a thickness in the range of about 0.2 nm (nanometers) to about 2.0 nm (nanometers). The first non-magnetic layer 130 may not have a texture. For example, the first non-magnetic layer 130 may be uniformly formed on the first vertical magnetic layer 124, and may not have a texture due to the small thickness.The first nonmagnetic layer 130 may include at least one selected from nonmagnetic metal elements containing a nonmagnetic transition metal. In an embodiment, the first non-magnetic layer 130 may be formed with a plurality of layers. For example, the first non-magnetic layer 130 may include a first lower metal compound layer 133, a first non-magnetic metal layer 136, and a first upper metal compound layer 139, which are sequentially stacked on the vertical magnetic layer 124. Although not shown in FIG. 2, the first nonmagnetic layer 130 may include a metal compound layer / nonmagnetic metal layer or a nonmagnetic metal layer / metal compound layer, which are sequentially stacked on the first vertical magnetic layer 124. The non-magnetic metal layer may include at least one selected from the group consisting of magnesium (Mg), aluminum (Al), titanium (Ti), chromium (Cr), ruthenium (Ru), copper (Cu), zinc (Zn), tantalum (Ta), gold (Au), silver (Ag), palladium (Pd), rhodium (Rh), iridium (Ir), molybdenum (Mo), vanadium (V), tungsten (W), niobium (Nb), zirconium (Zr), yttrium (Y), and / or hafnium (Hf). The first lower and upper metal compound layers 133, 139 may be a metal oxide, a metal nitride, a metal oxynitride, or a combination thereof. For example, the metal connection layer may be a connection of the metal layer. Conversely, the first non-magnetic layer 130 may include only a single metal layer or a plurality of metal layers.A first magnetic junction layer 141, a tunnel barrier 145, and a second magnetic junction layer 149 may be sequentially stacked on the first non-magnetic layer 130. The first magnetic junction layer 141, the tunnel barrier 145, and the second magnetic junction layer 149 may form a magnetic tunnel junction. The first transition magnetic layer 141 may be strongly exchange-coupled to the first vertical magnetic layer 123 through the first non-magnetic layer 130. A vertical magnetic anisotropy of the first magnetic transition layer 141 may be increased. The first magnetic transition layer 141 and the second magnetic transition layer 149 may include a soft magnetic material. When a magnetic memory cell is in operation, either the first magnetic junction layer 141 or the second magnetic junction layer 149 may serve as a reference layer, and the other may serve as a free layer. The magnetic transition layer serving as the free layer may have a lower saturation magnetization than that of the magnetic transition layer serving as the reference layer.A second non-magnetic layer 150 may be disposed on the second magnetic transition layer 149. The second non-magnetic layer 150 may be formed with a small thickness. For example, the second non-magnetic layer may be formed to have a thickness in a range from about 0.2 nm (nanometers) to about 2.0 nm (nanometers). The second non-magnetic layer 150 may not have a texture. For example, the second non-magnetic layer 150 may be uniformly formed on the second transition magnetic layer 149, and may not have a texture due to the thin thickness.A second vertical magnetic layer 163 may be disposed on the second non-magnetic layer 150. The second vertical magnetic layer 163 may be configured to have a magnetization direction vertical to the plane of the substrate 100. For example, the second vertical magnetic layer 163 may include alternately stacked non-magnetic layers 161 and ferromagnetic layers 162, wherein the ferromagnetic layers 162 may be formed with a thickness of one to multiple atoms. The magnetization direction of the ferromagnetic layers 162 may be vertical to the plane of the substrate 100. The second vertical magnetic layer 163 may be exchange-coupled to the second transition magnetic layer 149 through the second non-magnetic layer 150.A capping layer 170 may be formed on the second vertical magnetic layer 163. The capping layer 170 may include at least one selected from the group consisting of tantalum (Ta), aluminum (Al), copper (Cu), gold (Au), silver (Ag), titanium (Ti), ruthenium (Ru), magnesium (Mg), tantalum nitride (TaN), and / or titanium nitride (TiN).Referring to FIG. 3, a modified example of a magnetic memory device according to the embodiments of the inventive concept will be described. A seed layer 115 and a first vertical magnetic layer 124 are sequentially disposed on a substrate 100 and a lower electrode 110. The seed cell 115 may include a single metal layer and a plurality of metal layers. The first vertical magnetic layer 124 may include a material having an axis vertical to the plane of the substrate 100 and may be easily magnetized. The first vertical magnetic layer 124 may include at least one selected from the group consisting of a metal having an L10crystal structure, a material having a hexagonal close-packed (hcp) lattice, and an amorphous RE-TM alloy. When the first vertical magnetic layer 124 includes an amorphous RE-TM alloy, the seed layer 115 may be omitted.A first non-magnetic layer 130 may be disposed on the first vertical magnetic layer 124. The first non-magnetic layer 130 may be formed with a small thickness. For example, the first non-magnetic layer 130 may be formed to have a thickness in a range from about 0.2 nm (nanometers) to about 2.0 nm (nanometers). The first non-magnetic layer 130 may not have a texture.The first nonmagnetic layer 130 may include at least one selected from nonmagnetic metal elements containing a nonmagnetic transition metal. In an embodiment, the first non-magnetic layer 130 may be formed with a plurality of layers. For example, the first non-magnetic layer 130 may include a first lower metal compound layer 133, a first non-magnetic metal layer 136, and a first upper metal compound layer 139 sequentially stacked on the vertical magnetic layer 124. In contrast to the illustration, the first non-magnetic layer 130 may include a metal compound layer / non-magnetic metal layer or a non-magnetic metal layer / metal compound layer sequentially stacked on the first vertical magnetic layer 124. Conversely, the first non-magnetic layer 130 may include only a single metal layer or a plurality of metal layers. The first vertical magnetic layer 123 may be exchange-coupled to the first transition magnetic layer 141 through the first non-magnetic layer 130.A first magnetic junction layer 141, a tunnel barrier 145, a second magnetic junction layer 149 may be sequentially stacked on the first non-magnetic layer 130. The first magnetic transition layer 141 and the second magnetic transition layer 149 may include a soft magnetic material. When a magnetic memory cell operates, either the first magnetic junction layer 141 or the second magnetic junction layer 149 may serve as a reference layer, and the other may serve as a free layer. The magnetic transition layer serving as a free layer may have a smaller saturation magnetization than that of the magnetic transition layer serving as a reference layer.A second non-magnetic layer 150 may be disposed on the second magnetic transition layer 149. The second non-magnetic layer 150 may be formed with a small thickness. For example, the second non-magnetic layer 150 may be formed to have a thickness in a range from about 0.2 nm (nanometers) to about 2.0 nm (nanometers). The second non-magnetic layer 150 may not have a texture.A second vertical magnetic layer 164 is disposed on the second non-magnetic layer 150. The second vertical magnetic layer 164 may be configured to have a magnetization direction vertical to the planes of a first magnetic junction layer and a second magnetic junction layer 141, 149 forming the magnetic tunnel junction. The second vertical magnetic layer 164 may be exchange-coupled to the second transition magnetic layer 149 through the second non-magnetic layer 150. For example, the second vertical magnetic layer 164 may include an amorphous RE-TM alloy. A capping layer 170 may be disposed on the second vertical magnetic layer 164.Referring to FIGS. 4A and 4C and 1, a method of forming a magnetic memory device according to embodiments of the inventive concept will be described. Some description may be omitted with reference to FIG. 1.Referring to FIG. 4A, a lower electrode 110 may be formed on a substrate 100. The lower electrode 110 may be formed on the substrate 100 and / or in the substrate 100.Non-magnetic layers 121 and ferromagnetic layers 122 may be alternately stacked on the lower electrode 110. The stacking number of the non-magnetic layers 121 and the ferromagnetic layers 122 may be in a range of about 2 to about 20. The ferromagnetic layers 122 may be formed with a thickness of one to more atoms. The non-magnetic layers 121 and ferromagnetic layers 122 may form a first vertical magnetic layer 123.Referring to FIG. 4B, a first lower metal compound layer 133 may be formed on the first vertical magnetic layer 123. A metal layer may be formed thin on the first vertical magnetic layer 123, followed by oxidation and / or nitriding to form the first lower metal compound layer 133. The metal layer may contain at least one selected from, for example, transition metals.A first non-magnetic metal layer 136 may be formed on the first lower metal interconnection layer 133. The first non-magnetic metal layer 136 may include at least one selected from non-magnetic metals, e.g., non-magnetic transition metals. For example, the first non-magnetic metal layer 136 and the first lower metal compound layer 133 may include at least one selected from the group consisting of magnesium (Mg), aluminum (Al), titanium (Ti), chromium (Cr), ruthenium (Ru), copper (Cu), zinc (Zn), tantalum (Ta), gold (Au), silver (Ag), palladium (Pd), rhodium (Rh), iridium (Ir), molybdenum (Mo), vanadium (V), tungsten (W), niobium (Nb), zirconium (Zr), yttrium (V) and / or hafnium (Hf). The first non-magnetic metal layer 136 may include a metal identical to the first lower metal compound layer 133.Referring to FIG. 4C, a first upper metal interconnect layer 139 is formed on the first non-magnetic metal layer 136. The first upper metal compound layer 139 may be formed by oxidation or nitriding on a top surface of the first non-magnetic metal layer 136. For the oxidation or nitriding, a small amount of oxidizing gas and / or nitriding gas may be provided on an upper surface of the first upper metal compound layer 139. Conversely, a separate metal layer may be formed on the first non-magnetic metal layer 136, followed by oxidation and / or nitriding to form the first upper metal compound layer 139, or a separate metal compound layer may be deposited to form the first upper metal compound layer 139.A first magnetic junction layer 141, a tunnel barrier 145, and a second magnetic junction layer 149 may be sequentially formed on the first upper metal interconnection layer 139. The first magnetic transition layer 141 and the second magnetic transition layer 149 may include a soft magnetic material. In an embodiment, the first magnetic transition layer 141 and the second magnetic transition layer 149 may include materials having mutually different saturation magnetizations. The first and second magnetic junction layers 149 may be formed in an amorphous state. In one embodiment, a method of oxidizing a top portion of the first magnetic transition layer 149 may be further included.The tunnel barrier 145 may include at least one selected from the group consisting of magnesium (Mg), titanium (Ti), aluminum (Al), an oxide of magnesium zinc (MgZn), and / or magnesium boron (MgB), and / or a nitride of titanium (Ti) and / or vanadium (V). Conversely, the tunnel barrier 145 may include a plurality of layers. The plurality of layers may be at least two layers selected from the group consisting of metal layers, metal oxide layers, metal nitride layers and / or metal oxide nitride layers. The tunnel barrier 145 may have a predetermined crystal structure, for example, a NaCl-type crystal structure.A second magnetic junction layer 149 may be formed on the tunnel barrier 145. When the second magnetic junction layer 149 is used as a free layer of a magnetic memory cell, the second magnetic junction layer 149 may have a smaller saturation magnetization than that of the first magnetic junction layer 141. Alternatively, the iron (Fe) content of the second magnetic transition layer 149 may be greater than or at least equal to that of the first magnetic transition layer 141.A top surface of the second magnetic transition layer 149 may be oxidized and / or nitrided. A pre-lower metal compound layer 152 may thus be formed in an upper portion of the second magnetic transition layer 149. A top surface of the second magnetic transition layer 149 may be oxidized and / or nitrided in the same manner as the top surface of the first non-magnetic metal layer 136. Conversely, an oxidation and / or nitriding process of the second magnetic transition layer 149 may be omitted.A second non-magnetic metal layer 156 may be formed on the second magnetic transition layer 149 and the pre-lower metal connection layer 152. The second non-magnetic metal layer 156 may include at least one selected from the group consisting of magnesium (Mg), aluminum (Al), titanium (Ti), chromium (Cr), ruthenium (Ru), copper (Cu), zinc (Zn), tantalum (Ta), gold (Au), silver (Ag), palladium (Pd), rhodium (Rh), iridium (Ir), molybdenum (Mo), vanadium (V), tungsten (W), niobium (Nb), zirconium (Zr), yttrium (V), and / or hafnium (Hf).Referring to FIG. 1, a second upper metal interconnection layer 149 is formed on the second non-magnetic metal layer 156. The second upper metal compound layer 159 may be formed by oxidizing or nitriding a top surface of the second non-magnetic metal layer 156. In the oxidation or nitriding, a small amount of oxidizing gas and / or nitriding gas may be provided on an upper surface of the second upper metal compound layer 159. Conversely, a separate metal layer may be formed on the second non-magnetic metal layer 156, followed by oxidation and / or nitriding to form the second upper metal compound layer 159, or one may deposit a separate metal compound layer to form the second upper metal compound layer 159.Non-magnetic layers 161 and ferromagnetic layers 162 may be alternately stacked on the second upper metal compound layer 159. The ferromagnetic layers 162 may be formed with a thickness of one to more atoms. The non-magnetic layers 161 and the ferromagnetic layers 162 may be included in a second vertical magnetic layer 163. The stacking number of the non-magnetic layers 161 and ferromagnetic layers 162 of the second vertical magnetic layer 163 may be different from that of the non-magnetic layers 121 and ferromagnetic layers 122 in the first vertical magnetic layer 123.Before and / or after formation of the second vertical magnetic layer 163, a anneal process may be performed. By the annealing method, the amorphous first and second magnetic junction layers 141, 149 having the tunnel barrier 145 as a seed layer can be crystallized. The annealing process may be a magnetic annealing process or another annealing process. Since the tunnel barrier 145 serves as a seed layer, the tunnel barrier 145 may have a crystal structure similar to that of the first and second magnetic junction layers 141, 149. Alternatively, surfaces of the first and second magnetic junction layers 141, 149 contacting the tunnel barrier 145 may have the same crystal planes as the surface of the tunnel barrier. For example, when the upper and lower surfaces of the tunnel barrier 145 correspond to a (001) crystal plane of a NaCl type crystal structure, surfaces of the first and second magnetic transition layers 141, 149 contacting the tunnel barrier 145 may be a (001) crystal plane of a body centered cubic structure.During the anneal, the first and second non-magnetic layers 130, 150 may prevent the crystallization of the first and second magnetic compound layers 141, 149 along the crystal structure of layers other than the tunnel barrier 145. For example, if the first and second non-magnetic layers 130, 150 are omitted, the crystallization of the first and second transition magnetic layers 141, 149 may be affected by the first and second vertical magnetic layers 123, 163. In this case, the first and second magnetic junction layers 141, 149 may not have crystal structures and / or crystal planes equal to those of the tunnel barrier 145. If the first and second magnetic junction layers 141, 149 have crystal structures and / or crystal planes other than those of the tunnel barrier 145, the resistance value of the magnetic tunnel junction including them can be significantly reduced. However, when the first and second non-magnetic layers 130, 150 are arranged between the first vertical magnetic layer 123 and the first transition magnetic layer 141 and / or between the second vertical magnetic layer 163 and the second transition magnetic layer 140 according to the embodiments of the inventive concept, the first and second vertical magnetic layers 123, 163 may not serve as a seed layer for crystallization of the first and second transition magnetic layers 141, 149. Accordingly, the crystal structures of the first and second magnetic junction layers 141, 149 can be aligned with the crystal structure of the tunnel barrier 145. Thereby, the magnetic resistance ratio of a magnetic tunnel junction including the same can be increased.A capping layer 170 may be formed on the second vertical magnetic layer 163. The capping layer 170 may include at least one selected from the group consisting of tantalum (Ta), aluminum (Al), copper (Cu), gold (Au), silver (Ag), titanium (Ti), ruthenium (Ru), magnesium (Mg), tantalum nitride (TaN), and / or titanium nitride (TiN).The first vertical magnetic layer 123, the first nonmagnetic layer 130, the first transition magnetic layer 141, the tunnel barrier 145, the second transition magnetic layer 149, the second nonmagnetic layer 150, the second vertical magnetic layer 163, and the capping layer 170 may be patterned. The patterning may be performed by a method selected from various patterning methods including photolithography and / or electron beam patterning. The patterning may be performed after all the layers are formed or after some of the layers are formed. When only some of the layers are patterned, additional patterning may be performed after the other of the layers are formed.Referring to FIG. 2, a method of forming a modified example of a magnetic memory device according to the embodiments of the inventive concept will be described. The description of the method of forming the elements described with reference to FIG. 1 is omitted.A seed layer 115 may be formed on a substrate 100. The seed layer 115 may include a single metal layer or a plurality of metal layers. The seed layer 115 may include a metal layer having a predetermined crystal structure. For example, the seed layer 115 may have at least one crystal structure selected from the group consisting of body-centered cubic (krz) lattice, face-centered cubic (kfz) lattice, and hexagonal close-packed (hcp) lattice.A first vertical magnetic layer 124 may be formed on the seed layer 115. The first vertical magnetic layer 124, which is deposited using the seed layer 115 as a seed, may have an hcp or an L10 crystal structure. When the first vertical magnetic layer 124 is formed of an amorphous RE-TM alloy, the seed layer 115 may be omitted.Referring to FIG. 3, a method of forming a modified example of a magnetic memory device according to the embodiments of the inventive concept will be described. The description of the method of forming the elements described with reference to FIGS. 1 and 2 will be omitted.A second vertical magnetic layer 164 is formed on a second non-magnetic layer 150. The second vertical magnetic layer 164 may include, for example, an amorphous RE-TM alloy. Although not shown, the second vertical magnetic layer 164 may include a plurality of ferromagnetic layers. A non-magnetic metal layer may be disposed between the ferromagnetic layers. The second vertical magnetic layer 124 may be modified in different shapes within the range of ferromagnetic material layers having a vertical direction of magnetization.(A second embodiment)Referring to FIG. 5, a magnetic memory device according to the second embodiments of the inventive concept will be described.A lower electrode 210 is disposed on a substrate 200. The substrate 200 may be a semiconductor-based semiconductor substrate. The substrate 200 may include a conductive region and / or an insulating region. The lower electrode 210 may be electrically connected to the conductive portion of the substrate 200. The lower electrode 210 may be disposed on the substrate 200 and / or in the substrate 200. The lower electrode 210 may include any one selected from the group consisting of a line, island, and / or plate.A pinning layer 226 is disposed on the bottom electrode 210. The pinning layer may include an antiferromagnetic material. For example, the pinning layer 226 may include at least one selected from the group consisting of PtMn, IrMn, FeMn, NiMn, MnO, MnS, MnTe, MnF 2, FeF 2, FeCl 2, FeO, CoCl 2, CoO, NiCl 2, NiO and / or Cr. The pinning layer 226 may fix the magnetization direction of an adjacent magnetic layer in one direction.A lower reference layer 227 may be provided on the pinning layer 226. The lower reference layer 227 may comprise a ferromagnetic material. For example, the lower reference layer 227 may include at least one selected from the group consisting of CoFeB, Fe, Co, Ni, Gd, Dy, CoFe, NiFe, MnAs, MnBi, MnSb, CrO 2, MnOFe 2 O 3, FeOFe 2 O 3, NiOFe 2 O 3, CuOFe 2 O 3, EuO and / or Y may comprise 3 Fe 5 O 12. The magnetization direction of the lower reference layer 227 may be fixed in one direction by the pinning layer 226. The one direction may be selected from directions parallel to the plane of the substrate 200. For example, the reference layer 227 may include at least one selected from the group consisting of a material L10crystal structure, a material having an hcp, and an amorphous RE-TM alloy. In this case, the magnetization direction of the lower reference layer 227 may be vertical (perpendicular) to the plane of the substrate 200.An exchange coupled reference layer 228 may be disposed on the lower reference layer 227. The exchange-coupled reference layer 228 may include at least one selected from the group consisting of ruthenium (Ru), iridium (Ir), chromium (Cr), and / or rhodium (Rh).An upper reference layer 241 may be formed on the exchange-coupled reference layer 228. The upper reference layer 241 may include iron (Fe). The upper reference layer 241 may include at least one selected from the group consisting of cobalt (Co) and / or nickel (Ni). The upper reference layer 241 may further include at least one of non-magnetic materials including boron (B), zinc (Zn), aluminum (Al), titanium (Ti), ruthenium (Ru), tantalum (Ta), silicon (Si), silver (Ag), gold (Au), copper (Cu), carbon (C), and / or nitrogen (N). The upper reference layer 241 may be exchange-coupled to the lower reference layer 227 through the exchange-coupled reference layer 228.A tunnel barrier 245 may be formed on the upper reference layer 241. The tunnel barrier 245 may include a non-magnetic material. The tunnel barrier 245 may include at least one selected from the group consisting of magnesium (Mg), titanium (Ti), aluminum (Al), an oxide of magnesium zinc (MgZn), and / or magnesium boron (MgB), and / or a nitride of titanium (Ti) and / or vanadium (V). For example, the tunnel barrier 245 may be a magnesium oxide (MgO) layer. Conversely, tunnel barrier 245 may include a plurality of layers including a metal layer and a metal interconnect layer.The tunnel barrier 245 may have a crystal structure similar to that of the upper reference layer 241. For example, the tunnel barrier 245 and the upper reference layer 241 may each have a NaCl type crystal structure and a body centered cubic structure. The interface between the tunnel barrier 245 and the upper reference layer 241 may include identical crystal planes. For example, the (001) crystal plane of the tunnel barrier 245 may include the (001) crystal plane of the upper reference layer 241.The lower free layer 249 may be disposed on the tunnel barrier 245. The lower free layer 249 may contain iron (Fe). The lower free layer 249 may contain at least one selected from the group consisting of cobalt (Co) and / or nickel (Ni). The upper reference layer 241 may further include at least one of non-magnetic materials including boron (B), zinc (Zn), aluminum (Al), titanium (Ti), ruthenium (Ru), tantalum (Ta), silicon (Si), silver (Ag), gold (Au), copper (Cu), carbon (C), and / or nitrogen (N).The iron (Fe) content in the lower free layer 249 may be higher than that in the upper reference layer 241. The reliability of a magnetic storage device including the upper reference layer 241 and the lower free layer 249 may be increased by a high iron content in the lower free layer 249. When the iron content in the reference layer between the reference layer and the free layer forming a magnetic tunnel junction is high, the magnetic memory cell including the magnetic tunnel junction may exhibit abnormal switching behavior. In one example, the magnetization direction of a free layer containing a relatively low iron content may not be maintained in a direction parallel to the magnetization direction of the reference layer. Accordingly, when the magnetic storage device is switched in a parallel state (a state in which the magnetization direction of the free layer is parallel to the magnetization direction of the reference layer), the magnetization direction of the free layer can be abnormally reversed. The reliability of a magnetic memory cell including the free layer may be deteriorated by these abnormal switching phenomena. However, the lower free layer 249 may have a higher iron content than the upper reference layer 241 according to the embodiments of the inventive concept. Accordingly, in a switching operation of a magnetic memory cell in a parallel state, the magnetization direction of the lower free layer 249 can be stably maintained in a parallel state to the magnetization direction of the upper reference layer 241. The magnetization direction of the lower free layer 249 cannot be abnormally reversed. Thereby, the reliability of the magnetic memory device including the lower free layer 249 can be enhanced.A free exchange coupled layer 265 may be disposed on the lower free layer 249. The free exchange-coupled layer 265 may include at least one selected from the group consisting of ruthenium (Ru), iridium (Ir), chromium (Cr), and / or rhodium (Rh).An upper free layer 266 may be disposed on the exchange coupling free layer 265. The upper free layer 266 may include a ferromagnetic metal. For example, the upper free layer 266 may include at least one selected from the group consisting of CoFeB, Fe, Co, Ni, Gd, Dy, CoFe, NiFe, MnAs, MnBi, MnSb, CrO 2, MnOFe 2 O 3, FeOFe 2 O 3, NiOFe 2 O 3, CuOFe 2 O 3, EuO and / or Y may comprise 3 Fe 5 O 12. When a magnetic memory cell operates, the direction of magnetization of the upper free layer 266 may be changed to a first direction or a second direction parallel to the plane of the substrate 200. The upper free layer 266 may include, as another example, at least one selected from amorphous RE-TM alloys. In this case, the magnetization direction of the upper free layer 266 may be changed to a first direction or a second direction vertical to the plane of the substrate 200 when a magnetic memory cell operates. The upper free layer 266 may be exchange-coupled to the lower free layer 249 through the exchange-coupling free layer 265.A top layer 270 is disposed on top of the top free layer 266. The capping layer 270 may include at least one selected from the group consisting of tantalum (Ta), aluminum (Al), copper (Cu), gold (Au), silver (Ag), titanium (Ti), tantalum nitride (TaN), and / or titanium nitride (TiN).Although not shown, the positions of the lower and upper free layers 249, 266 and the lower and upper reference layers 227, 241 may be changed. For example, the lower and upper free layers 249, 266 may be disposed below the tunnel barrier 245 and the lower and upper reference layers 227, 241 may be disposed above the tunnel barrier 245. In this case, an upper free layer 266, a replacement coupling free layer 265, and a lower free layer 249 may be sequentially stacked between the lower electrode 210 and the tunnel barrier 245, while an upper reference layer 241, a reference replacement coupling layer 228, and a lower reference layer 227 may be sequentially stacked between the tunnel barrier 245 and the cover layer 270.Referring to FIG. 6, a modified example of a magnetic memory device according to the second embodiments of the inventive concept will be described. The description of the elements described with reference to FIG. 5 may be omitted.A vertical lower reference layer 223 may be disposed on the lower electrode 210. The vertical lower reference layer 223 may include alternately stacked non-magnetic layers 221 and ferromagnetic layers 222. The ferromagnetic layers 222 may include at least one selected from the group consisting of iron (Fe), cobalt (Co), and / or nickel (Ni), while the non-magnetic layers 121 may include at least one selected from the group consisting of chromium (Cr), platinum (Pt), palladium (Pd), iridium (Ir), ruthenium (Ru), rhodium (Rh), osmium (Os), rhenium (Re), gold (Au), and / or copper (Cu). For example, the vertical lower reference layer 223 may include [Co / Pt]m, [Co / Pd]m, or [Ni / Pt]m (m is a stack number of each layer and a natural number of 2 or more). In some embodiments, the non-magnetic layers 221 and the ferromagnetic layers 222 may be stacked about 2 to about 20 times, respectively. When the current flows in a direction vertical to the substrate 200 and the planes of the vertically lower reference layers 223, the vertically lower reference layer 223 may be configured such that the magnetization direction thereof is parallel to the current. For this configuration, the ferromagnetic layers 222 may be formed thin with a thickness of one to multiple atomic layers.A vertical upper free layer 263 may be disposed on a lower free layer 249. The vertical upper free layer 263 may include alternately stacked non-magnetic layers 261 and ferromagnetic layers 262. The ferromagnetic layers 262 may include at least one selected from the group consisting of iron (Fe), cobalt (Co), and / or nickel (Ni), while the non-magnetic layers 261 may include at least one selected from the group consisting of chromium (Cr), platinum (Pt), palladium (Pd), iridium (Ir), ruthenium (Ru), rhodium (Rh), osmium (Os), rhenium (Re), gold (Au), and / or copper (Cu). For example, the vertical upper free layer 263 may include [Co / Pt]n, [Co / Pd]n, and / or [Ni / Pt]n (n is a stack number of each layer and a natural number of 2 or more). In some embodiments, the non-magnetic layers 261 and the ferromagnetic layers 262 may be stacked about 2 to about 20 times, respectively. The stack number n of non-magnetic layers 261 and ferromagnetic layers 262 in the vertical upper free layer 263 may be less than the stack number m of non-magnetic layers 221 and ferromagnetic layers 222 in the vertical lower reference layer 223.Referring to FIG. 5, a method of forming a magnetic memory device according to the second embodiments of the inventive concept will be described. A lower electrode 210 is formed on a substrate 200. The lower electrode 210 may be formed on a substrate 200 and / or in the substrate 200.A pinning layer 226 is formed on the lower electrode 210. Pinning layer 226 may include an antiferromagnetic material. In some embodiments, a seed layer may be formed in replacement of the pinning layer 226. The seed layer may include a metal having a predetermined crystal structure or a metal alloy.A lower reference layer 227 may be formed on the pinning layer 226. The lower reference layer 227 may include a ferromagnetic material.For example, the lower reference layer 227 may include at least one selected from the group consisting of CoFeB, Fe, Co, Ni, Gd, Dy, CoFe, NiFe, MnAs, MnBi, MnSb, CrO 2, MnOFe 2 O 3, FeOFe 2 O 3, NiOFe 2 O 3, CuOFe 2 O 3, EuO and / or Y may contain 3 Fe 5 O 12. The lower reference layer 227 may include, as another example, at least one selected from the group consisting of a material having an L10crystal structure, a material having a hexagonal close-packed (hcp) lattice, and an amorphous RE-TM alloy.An exchange coupled reference layer 228 may be formed on the lower reference layer 227. The exchange-coupled reference layer 228 may include at least one selected from the group consisting of ruthenium (Ru), iridium (Ir), chromium (Cr), and / or rhodium (Rh).An upper reference layer 241, a tunnel barrier 245, and a lower free layer 249 may be formed on the exchange coupled reference layer 228. The upper reference layer 241 and the lower free layer 249 may be formed in an amorphous state, while the tunnel barrier 245 may be formed in a NaCl type crystal state. The crystal structure of the upper reference layer 241 and the lower free layer 249 may be aligned with the crystal structure of the tunnel barrier 245 by a subsequent anneal process.A replacement free coupling layer 265 may be formed on the lower free layer 249. The exchange-coupled reference layer 228 may include at least one selected from the group consisting of ruthenium (Ru), iridium (Ir), chromium (Cr), and / or rhodium (Rh).An upper free layer 266 may be formed on the exchange coupling free layer 265. The upper free layer 266 may include a ferromagnetic metal. A capping layer 270 may be formed on top free layer 266.The layers stacked on the lower electrode 210 are patterned. The patterning may be performed by at least one method selected from various patterning methods including photolithography and electron beam. The patterning may be performed after all the layers are formed or after some layers are formed. If only some of the layers are patterned, additional patterning may be performed after the other of the layers are formed.Referring to FIG. 6, a method of forming a modified example of a magnetic memory device according to the second embodiments of the inventive concept will be described. Description of methods of forming elements previously described in FIG. 5 is omitted.Non-magnetic layers 221 and ferromagnetic layers 222 may be alternately stacked on the lower electrode 210. The ferromagnetic layers 222 may be deposited to a thickness of one to more atoms. The non-magnetic layers 221 and ferromagnetic layers 222 formed on the lower electrode 210 may form a vertically lower reference layer 223.Non-magnetic layers 261 and ferromagnetic layers 262 may be alternately stacked on the lower free layer 249. The ferromagnetic layers 262 may be formed with a thickness of one to more atoms. Non-magnetic layers 221 and ferromagnetic layers 222 formed on the lower free layer 249 may form a vertical upper free layer 263.The stacking number of the non-magnetic layers 221 and the ferromagnetic layers 222 in the vertical lower reference layer 223 may be larger than the stacking number of the non-magnetic layers 261 and the ferromagnetic layers 262 in the vertical upper free layer 262.(Third Embodiment)Referring to FIG. 7, a magnetic memory device according to the third embodiments of the inventive concept will be described. A lower electrode 320 is disposed on a substrate 310. The substrate 310 may be any one selected from various substrates including a semiconductor element-based substrate and a metal compound-based substrate. The substrate 310 may include a conductive region and / or an insulating region. Although the lower electrode 320 is illustrated as being disposed on the substrate 310, the electrode may be included in the substrate 310. The lower electrode 320 may be an electrode or an electrode contact. The lower electrode 320 may be electrically connected to the conductive region in the substrate 310. For example, the lower electrode 320 may be electrically connected to at least one selected from switching devices including a transistor and a diode included in the substrate 310.A seed layer 330 is disposed on the substrate 310. The seed layer 330 may contain metal atoms forming a hexagonal close-packed (hcp) lattice. As illustrated in FIG. 9, the hcp may be a grid including three A-axes, three B-axes forming a hexagonal plane with the A-axes, and C-axes substantially vertical to the hexagonal plane. A hexagonal plane formed by the A-axes and B-axes may be substantially parallel to the plane of the substrate 310, while the C-axes may be substantially vertical to the plane of the substrate 310. The (001) crystal plane of a crystal structure forming the seed layer 330 may be parallel to the plane of the substrate 310. The seed layer 330 may be formed to be thin. For example, the seed layer 330 may be formed to have a thickness in a range from about 1.0 nm (nanometers) to about 10.0 nm (nanometers). The seed layer 330 may include ruthenium (Ru) and / or titanium (Ti). Conversely, the seed layer 330 may contain metal atoms forming a face centered cubic (FC) lattice. For example, the seed layer 330 may include platinum (Pt), palladium (Pd), gold (Au), silver (Ag), copper (Cu), and / or aluminum (Al).A free magnetic substance 340 may be disposed on the seed layer 330. The free magnetic substance 340 may include a vertical free magnetic layer 342 contacting the seed layer 330 and a free magnetic transition layer 348 on the vertical free magnetic layer 342. In contrast to the illustration, the vertical free magnetic substance 342 and the free magnetic transition layer 348 may include a plurality of layers.The vertical free magnetic layer 342 may include a ferromagnetic material. The atoms contained in the vertical free magnetic layer 342 may form an hcp lattice. As shown in FIG. 9, the hcp lattice of the vertical free magnetic layer 342 may include an A-axis, a B-axis, and a C-axis. The C-axis of the hcp grid forming the vertical free magnetic layer 342 may be substantially vertical to the plane of the substrate 310. The (001) plane of the hcp grid forming the vertical free magnetic layer 342 may be parallel to the plane of the substrate 310. The easily magnetized axis of the vertical free magnetic layer 342 may be the C axis. Accordingly, the magnetization direction of the vertical free magnetic layer 342 may be vertical to the substrate. The vertical free magnetic layer 342 may have magnetic anisotropy in a direction vertical to the plane of the substrate 310.The ferromagnetic properties and the lattice structure of the vertical free magnetic layer 342 may be due to the type of atoms forming the vertical free magnetic layer 342 and / or the content of the atoms.In some embodiments, the vertical free magnetic layer 342 may include a disordered cobalt-platinum alloy having a platinum content in a range from about 10% to about 45% atomic percent. The platinum atom content of the vertical free magnetic layer 342 may be in a range of about 20% to 30% atomic percent. The vertical free magnetic layer 342 may further include a non-magnetic material. For example, the vertical free magnetic layer 342 may further include at least one selected from the group consisting of boron (B), chromium (Cr), and / or copper (Cu).In further embodiments, the vertical free magnetic layer 342 may further include Co 3 Pt, which is an ordered alloy. The vertical free magnetic layer 342 may further include a non-magnetic material. For example, the vertical free magnetic layer 342 may further include at least one selected from the group consisting of boron (B), chromium (Cr), silicon (Si), and / or copper (Cu).In further embodiments, the vertical free magnetic layer 342 may be formed in the form of a plurality of layers. In this case, the vertical free magnetic layer 342 may include a first free ferromagnetic layer having an hcp CP lattice and a second free ferromagnetic layer on the first free magnetic layer, which are sequentially stacked on the seed layer 330.The first free ferromagnetic layer may be one selected from embodiments of the above-described vertical free magnetic layer 342, while the second ferromagnetic layer may be an alloy containing at least one selected from the group consisting of iron (Fe), cobalt (Co), and / or nickel (Ni), and at least one selected from rare earth metals. For example, the rare earth metal may be at least one selected from the group consisting of terbium (Tb), dysprosium (Dy), and / or gadolinium (Gd). Conversely, the second free ferromagnetic layer may be at least one selected from ferromagnetic materials having an L10crystal structure including Fe 50 Pt 50, Fe 50 Pd 50, Co 50 Pt 50, Co 50 Pd 50 and / or Fe 50 Ni 50.The vertical free magnetic layer 342 may have a high vertical magnetic anisotropy by a crystal structure of the vertical free magnetic layer 342, i.e., a hcp lattice structure of the vertical free magnetic layer 342. In the specification, the vertical magnetic anisotropy means magnetic anisotropy in a direction vertical to the plane of the substrate 310. The reliability of a magnetic storage device including the vertical free magnetic layer 342 may be increased, and the operation performance of the magnetic storage may be reduced by the high vertical magnetic anisotropy. Specifically, the spin direction of many electrons among electrons transferred through the vertical free magnetic layer 342 can be aligned in a direction vertical to the plane of the substrate 310 through the vertical free magnetic layer 342. Accordingly, many electrons among the electrons transferred through the vertical free magnetic layer 342 can be substantially used in the writing operation of the magnetic storage device. Thereby, the reliability of a magnetic storage device can be increased, and the magnetic storage device can be operated using a relatively small amount of switching current.A lower exchange coupling control layer 344 may be disposed on the vertical free magnetic layer 342. The lower exchange coupling control layer 344 may include a magnetic material having a large exchange coupling constant or a non-magnetic material that can increase the surface magnetic anisotropy. For example, the lower exchange coupling control layer 344 may include at least one of iron (Fe), cobalt (Co), and / or nickel (Ni) having a large exchange coupling constant. The lower exchange coupling control layer 344 may further include platinum (Pt). The thickness of the lower exchange coupling control layer 344 may be in a range from about 0.2 nm (nanometers) to about 2.0 nm (nanometers). The lower exchange coupling control layer 344 may enhance exchange coupling between the vertical free magnetic layer 342 and a free magnetic transition layer 348 to be described. Since the vertical free magnetic layer 342 has high magnetic anisotropy in a direction vertical to the plane of the substrate, the free magnetic transition layer 348 exchange-coupled by the vertical free magnetic layer 342 and the lower exchange coupling control layer 344 may also have high magnetic anisotropy in a direction vertical to the plane of the substrate 310.As another example, the exchange coupling lower control layer 344 may include at least one selected from metal elements containing a transition metal. The lower exchange coupling control layer 344 may include at least one selected from non-magnetic metals including titanium (Ti), chromium (Cr), ruthenium (Ru), rhodium (Rh), copper (Cu), magnesium (Mg), zinc (Zn), aluminum (Al), tantalum (Ta), palladium (Pd), and / or platinum (Pt). Accordingly, the lower exchange coupling control layer 344 can increase the vertical magnetic anisotropy of the surface of the adjacent magnetic layers.In an embodiment, the lower exchange coupling control layer 344 may further include an oxide layer on the surface of the lower exchange coupling control layer 344. The oxide layer may be an oxide of a material forming the surface of the lower exchange coupling control layer 344.A free magnetic transition layer 348 may be disposed on the lower exchange coupling control layer 344. The free magnetic transition layer 348 may have high vertical anisotropy through the lower exchange coupling control layer 344 and / or the vertical free magnetic layer 342. For example, the free magnetic transition layer 348 may be strongly exchange-coupled by the vertical free magnetic layer 342 and the lower exchange coupling control layer 344 having high vertical anisotropy. Further, for example, the vertical magnetic anisotropy of the surface of the free magnetic transition layer 348 may be increased by the lower exchange coupling control layer containing the non-magnetic metals.The free magnetic transition layer 348 may include a soft magnetic material. The free magnetic transition layer 348 may have a low attenuation constant and a high spin polarization ratio. For example, the free magnetic transition layer 348 may contain cobalt (Co), iron (Fe), and / or nickel (Ni) atoms. The free magnetic transition layer 348 may further include at least one of non-magnetic materials consisting of boron (B), zinc (Zn), aluminum (Al), titanium (Ti), ruthenium (Ru), tantalum (Ta), silicon (Si), silver (Ag), gold (Au), copper (Cu), carbon (C), and / or nitrogen (N). In particular, the free magnetic transition layer 348 may include CoFe and / or NiFe, and may further include boron (B). In order to further reduce the saturation magnetization of the free magnetic transition layer 348, the free magnetic transition layer 348 may further include at least one selected from the group consisting of titanium (Ti), aluminum (Al), silicon (Si), magnesium (Mg), tantalum (Ta), and / or silicon (Si). As the saturation magnetization decreases, the switching current of a magnetic memory cell including the free magnetic transition layer 348 may be decreased.Although not shown, the free magnetic transition layer 348 may include a plurality of magnetic layers. For example, the free magnetic transition layer 348 may include a first free ferromagnetic layer, a free non-magnetic layer, and a second free ferromagnetic layer, i.e., an artificial ferromagnetic (SAF) layer, sequentially stacked on the lower exchange coupling control layer 344. The free magnetic transition layer 348 may include magnetic layers having a variable magnetization direction in various shapes.The magnetization direction of at least one layer of a plurality of layers constituting the free magnetic substance 340 may be changed. For example, the free magnetic transition layer 348 may have a variable magnetization direction. The magnetization direction of the free magnetic transition layer 348 may change in a first direction vertical to the substrate 310 or in a second direction anti-parallel to the first direction by electrical and / or magnetic factors provided from the outside on the free magnetic transition layer 348.A tunnel barrier 350 may be disposed on the free magnetic substance 340. Tunnel barrier 350 may have a thickness less than the spin diffusion distance. The tunnel barrier 350 may include a non-magnetic material. In some embodiments, tunnel barrier 350 may be formed of an insulating material layer. For example, the tunnel barrier 350 may include at least one selected from the group consisting of magnesium (Mg) / magnesium oxide (MgO), magnesium oxide (MgO) / magnesium (Mg), and / or magnesium (Mg) / magnesium oxide (MgO) / magnesium (Mg).A magnetic reference substance 360 may be formed on the tunnel barrier 350. The reference magnetic substance 360 may include a reference transition magnetic layer 361, a lower exchange coupling control layer 362, and the reference vertical magnetic layer 363 sequentially stacked on the tunnel barrier 350. A plurality of upper non-magnetic reference layers 364 and ferromagnetic reference layers 365 may be alternately stacked on the vertical magnetic reference layer 363.The reference magnetic transition layer 361 may include a soft magnetic material. For example, the reference magnetic transition layer 361 contains cobalt (Co), iron (Fe), and / or nickel (Ni), and the contents of atoms can be determined such that the saturation magnetization of the reference magnetic transition layer 361 can be lowered. The reference magnetic transition layer 361 may have a low attenuation constant and a high spin polarization ratio. To this end, the reference magnetic transition layer 361 may further include at least one of nonmagnetic materials including boron (B), zinc (Zn), aluminum (Al), titanium (Ti), ruthenium (Ru), tantalum (Ta), silicon (Si), silver (Ag), gold (Au), copper (Cu), carbon (C), and / or nitrogen (N). For example, the reference magnetic transition layer 361 may include CoFe and / or NiFe, and may further include boron. Moreover, the reference magnetic transition layer 361 may further include at least one selected from non-magnetic elements including titanium (Ti), aluminum (Al), silicon (Si), magnesium (Mg), and / or tantalum (Ta). The content of the selected non-magnetic element in the reference magnetic transition layer 361 may be in a range of about 1% to about 15% atomic percent.The free magnetic junction layer 348, the tunnel barrier 350, and the reference magnetic junction layer 361 may form a magnetic tunnel junction. A magnetic memory cell according to the embodiments of the inventive concept may store data using the difference of resistance values whether the magnetization directions of the two magnetic substances constituting the magnetic tunnel junction of the free magnetic junction layer 348 and the reference magnetic junction layer 361 are parallel or antiparallel to each other. In particular, according to the directions of electrons transferred through the magnetic tunnel junction, the magnetization direction of the free magnetic transition layer 348 may be changed.For example, when electrons move in a direction from the free magnetic transition layer 348 to the reference magnetic transition layer 361, electrons having a spin in a first direction of the magnetization direction parallel to electrons having the reference magnetic transition layer 361 may be transferred through the reference magnetic transition layer 361, while electrons having a spin in a second direction of magnetization antiparallel to electrons having the reference magnetic transition layer 361 may not be transferred (e.g., reflected) through the reference magnetic transition layer 361 and are transferred to the free magnetic transition layer 348. The magnetization direction of the free magnetic transition layer 348 may be a second direction by electrons spin-in the second direction. Accordingly, the reference magnetic junction layer 361 and the free magnetic junction layer 348 may have a magnetization direction antiparallel to each other. A magnetic tunnel junction formed by magnetic substances having magnetization directions antiparallel to each other may have a relatively high resistance value. In the present embodiments, the first direction and the second direction may be directions substantially vertical (perpendicular) to the plane of the substrate 310.For another example, as electrons move from the reference magnetic transition layer 361 to the free magnetic transition layer 348, electrons having spin in a first direction transferred through the reference magnetic transition layer 361 may arrive at the free magnetic transition layer 348. The magnetization direction of the free magnetic transition layer 348 may be changed in the first direction by electrons spin-in the first direction that have arrived at the free magnetic transition layer 348. Accordingly, the reference magnetic transition layer 361 and the free magnetic transition layer 348 may have a magnetization direction in a first direction. A magnetic tunnel junction formed by magnetic substances having magnetization directions parallel to each other may have a relatively low resistance value.In this way, the resistance values of the magnetic tunnel junction can be varied according to the direction of electrons flowing through the magnetic tunnel junction. Data may be stored in the magnetic storage device using the difference in resistance values.An upper exchange coupling control layer 362 may be disposed on the magnetic reference transition layer 361. The upper exchange coupling control layer 362 may include a material having a large exchange coupling constant, e.g., a ferromagnetic metal or a material capable of controlling the orientation of a magnetic substance, e.g., a nonmagnetic metal. The exchange coupling upper control layer 362 may include at least one selected from the group consisting of iron (Fe), cobalt (Co), and / or nickel (Ni). For example, the exchange coupling upper control layer 364 may include at least one selected from the group consisting of titanium (Ti), chromium (Cr), ruthenium (Ru), rhodium (Rh), copper (Cu), magnesium (Mg), zinc (Zn), aluminum (Al), tantalum (Ta), palladium (Pd), and / or platinum (Pt). In some embodiments, the exchange coupling upper control layer 362 may further include an oxide layer on the surface of the exchange coupling upper control layer 362. The oxide layer may be a layer formed by oxidation of some of the exchange coupling upper control layer 362. The function and composition of the upper exchange coupling control layer 362 may be substantially identical to that of the lower exchange coupling control layer 344.A vertical magnetic reference layer 363 may be disposed on the upper exchange coupling control layer 362. The vertical magnetic reference layer 363 may include a ferromagnetic material. The atoms forming the vertical magnetic reference layer 363 may form a crystal structure having a readily magnetized axis substantially vertical to the plane of the substrate 310. For example, the vertical magnetic reference layer 363 may include cobalt (Co) and / or platinum (Pt), ordered alloy, or disordered alloy, and the C-axis of the hcp lattice may be vertical to the plane of the substrate 310. Accordingly, the vertical anisotropy of the vertical magnetic reference layer 363 can be significantly increased. The vertical magnetic reference layer 363 may further include at least one selected from the group consisting of boron (B), chromium (Cr), silicon (Si), and / or copper (Cu).An upper reference magnetic layer 364, 365 may be disposed on the upper exchange coupling control layer 363. The upper magnetic reference layer 364, 365 may include alternately stacked non-magnetic reference layers 364 and ferromagnetic reference layers 365. The reference non-magnetic layer 364 may include at least one selected from the group consisting of iron (Fe), cobalt (Co), and / or nickel (Ni), while the reference ferromagnetic layers 365 may include at least one selected from the group consisting of chromium (Cr), platinum (Pt), palladium (Pd), iridium (Ir), ruthenium (Ru), rhodium (Rh), osmium (Os), rhenium (Re), gold (Au), and / or copper (Cu). The upper reference magnetic layer 364, 365 may include [Co / Pb]n, [Co / Pt]n, or [Ni / Pt]n (n is a natural number of 2 or more). The stack numbers of the magnetic reference layers 364 and ferromagnetic reference layers 365 may be in a range of about 2 to about 11 times. The reference ferromagnetic layers 365 may be formed with a very small thickness. For example, the reference ferromagnetic layers 365 may be formed with an atomic layer thickness. The magnetization direction of the ferromagnetic reference layer 365 may be vertical to the plane of the substrate 310.The upper reference magnetic layers 364, 365 may be arranged in various shapes. For example, the upper reference magnetic layers 364, 365 may include a first reference ferromagnetic layer, a non-magnetic reference layer, and a second reference ferromagnetic layer, i.e., an artificial antiferromagnetic (SAF) layer, sequentially stacked on the vertical reference magnetic layer 363.A capping layer 370 may be disposed on the upper magnetic reference layers 364, 365. The capping layer 370 may further include at least one selected from the group consisting of tantalum (Ta), aluminum (Al), copper (Cu), gold (Au), silver (Ag), titanium (Ti), tantalum nitride (TaN), and / or titanium nitride (TiN).Referring to FIGS. 7 and 8, an exemplary method of forming a magnetic memory device will be described.Referring to FIG. 8, a lower electrode 320 is formed on a substrate 310. The lower electrode 320 may include a metal or a metal compound.A seed layer 330 is formed on the bottom electrode 320. The seed layer 330 may include metals having an hcp lattice or a face centered cubic (kfz) lattice. For example, the seed layer 330 may include at least one selected from the group consisting of ruthenium (Ru), titanium (Ti), platinum (Pt), palladium (Pd), gold (Au), silver (Ag), copper (Cu), and / or aluminum (Al). The seed layer 330 may be formed with a relatively small thickness. For example, the seed layer 330 may be formed to have a thickness in a range from 0.2 nm (nanometers) to about 2.0 nm (nanometers).A vertical free magnetic layer 342 is formed on the seed layer 330. The crystal structure of the vertical free magnetic layer 342 may be aligned with the crystal structure of the seed layer 330. For example, the vertical free magnetic layer 342 may be formed with an hcp lattice that is the same as the crystal structure of the seed cell 330. The vertical free magnetic layer 342 may include cobalt (Co) and / or platinum (Pt). The vertical free magnetic layer 342 may include an ordered alloy or an ordered alloy of cobalt (Co) and platinum (Pt).The vertical free magnetic layer 342 grown using the seed layer 330 as a seed may be formed by a relatively low temperature method. For example, the vertical free magnetic layer 342 formed using the seed layer 330 as a seed may be deposited at room temperature.In the case of a magnetic memory device having the magnetization direction of magnetic substances vertical to a substrate, a magnetic substance having a crystal structure having a large vertical anisotropy, for example, a ferromagnetic substance constituted by an ordered L10 alloy is used. In order to form a ferromagnetic substance having the ordered L10 alloy, a plurality of seed layers including a chromium (Cr) seed layer having a kfz lattice and a platinum (Pt) seed layer having a krz lattice may be required. The plurality of layers is formed thicker than a single seed layer. This can increase the size of a device containing the seed layer. During a patterning process of the seed layer, other magnetic layers and isolation layers may be contaminated by etching by-products of the seed layer. In particular, when the tunnel barrier described below is soiled by etching by-products of the seed layer, a short-circuit phenomenon may occur on the tunnel barrier to degrade the function of the memory. Moreover, the ordered L10 alloy may be formed using a high temperature deposition process at 400° C. or higher and / or using a high temperature annealing process at 600° C. or higher.Conversely, if a vertical free magnetic layer 342 having an hcp lattice is formed according to embodiments of the inventive concept, the seed layer 330 may be formed as a single layer. Accordingly, the thickness of the seed layer 330 may be less than that of a plurality of layers. The crystal structure of the vertical free magnetic layer 342 may have a high dependence on the seed layer 330. Accordingly, the vertical free magnetic layer 342 may be aligned with the crystal structure of the seed layer 330, for example, even at a low process temperature. That is, a high temperature deposition process or high temperature annealing process need not be essential.A lower exchange coupling control layer 344 may be formed on the vertical free magnetic layer 342. The lower exchange coupling control layer 344 may include a ferromagnetic metal having a large exchange coupling constant, for example, at least one selected from metals including iron (Fe), cobalt (Co), and / or nickel (Ni). Conversely, the lower exchange coupling control layer 344 may be a nonmagnetic material that increases the surface magnetic anisotropy of an adjacent magnetic substance or controls the crystal orientation of a magnetic substance to be formed on the lower exchange coupling control layer 344. For example, the lower exchange coupling control layer 344 may include at least one selected from the group consisting of titanium (Ti), chromium (Cr), ruthenium (Ru), rhodium (Rh), copper (Cu), magnesium (Mg), zinc (Zn), aluminum (Al), tantalum (Ta), palladium (Pd), and / or platinum (Pt). In some embodiments, the surface of the lower exchange coupling control layer 344 may be oxidized. A method for the oxidation may include introducing a minute amount of oxygen into a chamber in which a product in which the vertical free magnetic layer 342 has been formed is charged before forming the lower exchange coupling control layer 344, or an oxidation layer may be formed by introducing a minute amount of oxygen into the chamber after forming the lower exchange coupling control layer 344 with an atomic layer thickness and then forming the remaining lower exchange coupling control layer 344.A free magnetic transition layer 348 may be formed on the lower exchange coupling control layer 344. The vertical anisotropy of the free magnetic transition layer 348 may be increased by the vertical free magnetic layer 344 and / or the lower exchange coupling control layer 344. In particular, the crystallization of the free magnetic transition layer 348 into the crystal structure of the vertical free magnetic layer 342 may be prevented and / or reduced by the crystal structure of the lower exchange coupling control layer 344. For example, when the lower exchange coupling control layer 344 is omitted, the free magnetic transition layer 348 formed in an amorphous state may be crystallized into the crystal structure of the vertical free magnetic layer 342 by a heat treatment method. In this case, the crystal structure of the free magnetic transition layer 348 may be oriented by the crystal structure of the vertical free magnetic layer 342, i.e., a (011) crystal plane other than a (001) crystal plane of a krz structure, and then the magnetic resistance ratio of a magnetic tunnel junction including the free magnetic transition layers 348 may be decreased. However, since the vertical free magnetic layer 342 is separated from the free magnetic transition layer 348 by the lower exchange coupling control layer 344, the crystal structure of the free magnetic transition layer 348 cannot be aligned with the crystal structure of the vertical free magnetic layer 342. Accordingly, the magnetic resistance ratio of a magnetic tunnel junction can be increased.Referring again to FIG. 7, a tunnel barrier 350 may be formed from the free magnetic transition layer 348. The tunnel barrier may include at least one selected from the group consisting of magnesium (Mg), titanium (Ti), aluminum (Al), an oxide of magnesium zinc (MgZn) and / or magnesium boron (MgB) and / or a nitride of titanium (Ti) and / or vanadium (V). For example, the tunnel barrier 350 may be a magnesium oxide (MgO) layer. Conversely, tunnel barrier 350 may include a plurality of layers. For example, the tunnel barrier may include magnesium (Mg) / magnesium oxide (MgO), magnesium oxide (MgO) / magnesium (Mg) and / or magnesium (Mg) / magnesium oxide (MgO) / magnesium (Mg). The tunnel barrier 350 may be formed by depositing the metal oxide or metal nitride on the free magnetic transition layer 348 or by forming a metal layer on the free magnetic transition layer 348 and then oxidizing the metal layer. In an embodiment, the tunnel barrier 350 may have a predetermined crystal structure. For example, the tunnel barrier 350 may have a NaCl type crystal structure (face centered cubic lattice structure).A magnetic reference transition layer 361 may be formed on the tunnel barrier 350. The reference magnetic transition layer 361 may have a relatively small saturation magnetization. The reference magnetic transition layer 361 may include a soft magnetic material. The reference magnetic transition layer 361 may further include a non-magnetic material. The reference magnetic transition layer 361 may have the same magnetic properties as those of the free magnetic transition layer 348. Conversely, the reference magnetic transition layer 361 may have different magnetic properties than that of the free magnetic transition layer 348. For example, the product of the thickness of the reference magnetic transition layer 361 and the saturation magnetization of the reference magnetic transition layer 361 may be greater than that of the thickness of the free magnetic transition layer 348 and the saturation magnetization of the free magnetic transition layer 348.The crystal structure of the reference magnetic junction layer 361 may be aligned with the tunnel barrier 350. For example, when the tunnel barrier 350 is formed of a magnesium oxide (MgO) having a (001) crystal plane of a NaCl (face-centered cubic lattice) structure parallel to the plane of the substrate 310, the reference magnetic transition layer 361 may be aligned with the crystal structure of the tunnel barrier 350. Accordingly, the vertical magnetic anisotropy of the reference magnetic transition layer 361 can be increased. The crystallization of the reference magnetic transition layer 361 may be performed by a heat treatment method.An upper exchange coupling control layer 362 may be formed on the magnetic reference transition layer 361. The exchange coupling upper control layer 362 may include a magnetic material having a large exchange coupling constant. Accordingly, exchange coupling between the reference vertical magnetic layer 363 and the reference magnetic transition layer 361 may be increased to increase the vertical magnetic anisotropy of the reference magnetic transition layer 361. The upper exchange coupling control layer 362 may serve as a seed layer and may be aligned such that the easily magnetizable axis of the vertical magnetic reference layer 363 is vertical to the plane of the substrate 310. In some embodiments, the surface of the upper exchange coupling control layer 362 may be oxidized. A method of oxidation may include introducing a minute amount of oxygen into a chamber into which a product in which the reference magnetic transition layer 361 has been formed is introduced before formation from the exchange coupling upper control layer 362, or an oxidation layer may be formed by introducing a minute amount of oxygen into the chamber after formation of the exchange coupling upper control layer 362 having an atomic layer thickness and then forming the remaining exchange coupling upper control layer 362.A vertical reference magnetic layer 363 may be formed on the reference magnetic transition layer 361. The vertical magnetic reference layer 363 may be an amorphous ferromagnetic layer. For example, the vertical magnetic reference layer 363 may be formed of an amorphous cobalt (Co) and / or platinum (Pt) alloy. The vertical magnetic reference layer 363 may include at least one selected from the group consisting of boron (B), chromium (Cr), silicon (Si), and / or copper (Cu).An upper reference magnetic layer 364, 365 may be formed on the vertical reference magnetic layer 363. Non-magnetic reference layers 364 and ferromagnetic reference layers 365 may be alternately stacked multiple times to form the upper magnetic reference layer 364, 365. The reference ferromagnetic layers 365 may be formed with a very small thickness. The reference ferromagnetic layers 365 may be formed with an atomic layer thickness.The upper magnetic reference layer 364, 365 may be formed in various shapes. For example, the upper reference magnetic layer 364, 365 may include a first reference ferromagnetic layer, a non-magnetic reference layer, and a second reference ferromagnetic layer, i.e., an artificial antiferromagnetic (SAF) layer, which are sequentially stacked on the vertical reference magnetic layer 363.When the vertical reference magnetic layer 363 and / or the upper exchange coupling control layer 362 is disposed between the reference non-magnetic layer 364 and the reference transition magnetic layer 361, the magnetic resistance ratio of a magnetic tunnel junction including the reference transition magnetic layer 361 can be increased. In particular, when the reference non-magnetic layer 364 is formed directly on the reference magnetic transition layer 361, a metal forming the reference non-magnetic layer 364 may react with a metal forming the reference magnetic layer 361 during a heat treatment process to form a layer having no magnetic properties. The magnetic resistance ratio of the magnetic tunnel junction can be significantly reduced by the layer having no magnetic properties.In some examples, the reference magnetic transition layer 361 may be formed thin with a thickness equal to or less than a predetermined critical thickness. In this case, the reference magnetic transition layer 361 may be consumed by reaction with the reference non-magnetic layer 364 to reduce the magnetic resistance ratio. Conversely, since the vertical reference magnetic layer 363 and / or the exchange coupling upper control layer 364 is / are formed between the vertical reference transition magnetic layer 361 and the reference non-magnetic layer 364 according to the embodiments of the inventive concept, a layer having no magnetic properties may not be formed. Accordingly, the reference magnetic transition layer 361 is not unnecessarily consumed. Thereby, the magnetic resistance ratio of a magnetic tunnel junction including the reference magnetic transition layer 361 can be increased.A capping layer 370 may be formed on the upper magnetic reference layer 364, 365. The capping layer 370 may include at least one selected from the group consisting of tantalum (Ta), aluminum (Al), copper (Cu), gold (Au), silver (Ag), titanium (Ti), tantalum nitride (TaN), and / or titanium nitride (TiN).The layers stacked on the substrate 310 may be patterned. The patterning may be performed after all the layers are stacked from the lower electrode 310 to the cap layer 370, or the patterning of some layers may be performed before the stacking of the other layers. The patterning may be performed using an ion beam method and / or a photolithography method. The patterning may include performing an anisotropy etching process.(Fourth Embodiment)Referring to FIG. 10, a magnetic memory device according to the fourth embodiments of the inventive concept will be described. A lower electrode 420 is disposed on a substrate 410. The substrate 410 may include a conductive region and / or an insulating region. The bottom electrode 420 may be electrically connected to the conductive region in the substrate 410.A seed layer 430 is disposed on the lower electrode 420. The seed layer 430 may include hcp lattice-forming metal atoms. The hcp C-axes may be substantially vertical to the plane of the substrate 410.A magnetic reference substance 440 may be disposed on the seed layer 430. The reference magnetic substance 440 may include a vertically magnetic reference layer 442, a lower exchange coupling control layer 444, and / or a reference magnetic transition layer 448 sequentially stacked on the seed layer 430.The vertically magnetic reference layer 442 may include a ferromagnetic material. The vertically magnetic reference layer 442 may have a readily magnetized axis in a direction vertical to the substrate 410. For example, the vertical magnetic reference layer 442 may include a hexagonal close-packed (hcp) grid. As shown in FIG. 9, the hexagonal close-packed (hcp) lattice of the reference vertical magnetic layer 442 may include an A-axis, a B-axis, and a C-axis. The C-axis of the hcp lattice forming the vertical reference magnetic layer 442 may be substantially parallel to the C-axis forming the seed layer 430. The C-axis of the hcp lattice forming the vertical reference magnetic layer 442 may be substantially vertical to the plane of the substrate 410. The easily magnetized axis of the vertical magnetic reference layer 442 may be the C axis. Accordingly, the magnetization direction of the vertical magnetic reference layer 442 may be vertical to the substrate 410.In one example, the vertical magnetic reference layer 442 may include a disordered cobalt-platinum (CoPt) alloy having a platinum content in the range of about 10% to about 45% atomic percent. The platinum atom content in the vertical magnetic reference layer 442 may be in a range from about 20% to about 30% atomic percent. The vertically magnetic reference layer 442 may include a non-magnetic material. For example, the vertical magnetic reference layer 442 may further include at least one selected from the group consisting of boron (B), chromium (Cr), and / or copper (Cu).In another example, the vertically magnetic reference layer 442 may include Co 3 Pt that is an ordered alloy. The vertically magnetic reference layer 442 may further include a non-magnetic material. For example, the vertical magnetic reference layer 442 may further include at least one selected from the group consisting of boron (B), chromium (Cr), silicon (Si), and / or copper (Cu).In another example, the vertically magnetic reference layer 442 may include a plurality of layers. In this case, the vertically magnetic reference layer 442 may include a first reference ferromagnetic layer having an hcp lattice and a second reference ferromagnetic layer on the first reference ferromagnetic layer, which are sequentially stacked on the seed layer 430. The first ferromagnetic reference layer may be one selected from various embodiments of the vertical magnetic reference layer 442 described above, while the second ferromagnetic reference layer may be an alloy containing at least one selected from the group consisting of iron (Fe), cobalt (Co) and / or nickel (Ni) and at least one selected from rare earth metals. For example, the rare earth metal may be at least one selected from the group consisting of terbium (Tb), dysprosium (Dy), and / or gadolinium (Gd). Conversely, the second ferromagnetic reference layer may be at least one selected from among ferromagnetic materials having an L10crystal structure including Fe 50 Pt 50, Fe 50 Pd 50, Co 50 Pt 50, Co 50 Pd 50 and / or Fe 50 Ni 50. The reference vertical magnetic layer 442 may have high vertical anisotropy by the hcp structure of the reference vertical magnetic layer 442. Accordingly, the resistance distribution and switching current characteristics of a magnetic memory device including the vertically magnetic reference layer 442 can be improved.A lower exchange coupling control layer 444 may be disposed on the vertical magnetic reference layer 442. The under the exchange coupling control layer 444 may include a magnetic material having a large exchange coupling constant or a non-magnetic material that can increase the surface magnetic anisotropy. For example, the lower exchange coupling control layer 444 may include at least one selected from iron (Fe), cobalt (Co), and / or nickel (Ni) having a high exchange coupling constant. The lower exchange coupling control layer 444 may further include platinum (Pt). The thickness of the lower exchange coupling control layer (444) may be in a range from about 0.2 nm (nanometers) to about 2.0 nm (nanometers). The lower exchange coupling control layer 444 may enhance exchange coupling between the vertical reference magnetic layer 442 and a reference transition magnetic layer 448 to be described. In addition, since the reference vertical magnetic layer 442 has a high vertical anisotropy described above, the reference magnetic transition layer 448 exchange-coupled by the reference vertical magnetic layer 442 and the exchange coupling control lower layer 444 may have a high vertical anisotropy.The lower exchange coupling control layer 444 may include, as another example, at least one selected from non-magnetic metals including titanium (Ti), chromium (Cr), ruthenium (Ru), rhodium (Rh), copper (Cu), magnesium (Mg), zinc (Zn), aluminum (Al), tantalum (Ta), palladium (Pd), and / or platinum (Pt). The non-magnetic metals can control the orientation of the crystal structures of adjacent magnetic layers. In some embodiments, the lower exchange coupling control layer 444 may include an oxidation layer on the surface of the lower exchange coupling control layer 444. The oxidation layer may be a layer in which the surface of the lower exchange coupling control layer 444 is oxidized. The surface magnetic anisotropy of the adjacent magnetic layers can be enhanced by the lower exchange coupling control layer 444.A tunnel barrier 450 may be disposed on the reference magnetic transition layer 448. The tunnel barrier 450 may include at least one selected from the group consisting of magnesium (Mg), titanium (Ti), aluminum (Al), an oxide of magnesium zinc (MgZn), and / or magnesium boron (MgB), and / or a nitride of titanium (Ti) and / or vanadium (V). The tunnel barrier 450 may include a plurality of layers. For example, tunnel barrier 450 may include magnesium (Mg) / magnesium oxide (MgO), magnesium oxide (MgO) / magnesium (Mg), and / or magnesium (Mg) / magnesium oxide (MgO), magnesium oxide (MgO) / magnesium (Mg).A free magnetic substance 460 may be disposed on the tunnel barrier 450. The free magnetic substance 460 may include a free magnetic transition layer 461 contacting the tunnel barrier 450, an exchange coupling control layer 463 on the free magnetic transition layer 461, and an upper free magnetic layer 466 on the upper exchange coupling control layer 463.The free magnetic transition layer 461 may include a soft magnetic material. The free magnetic transition layer 461 may have a low saturation magnetization. The free magnetic transition layer 461 may also have a low attenuation constant and a high spin polarization ratio. The free magnetic transition layer 461 may include at least one selected from the group consisting of cobalt (Co), iron (Fe), and / or nickel (Ni). The free magnetic transition layer 461 may further include at least one selected from non-magnetic materials including boron (B), zinc (Zn), aluminum (Al), titanium (Ti), ruthenium (Ru), tantalum (Ta), silicon (Si), silver (Ag), gold (Au), copper (Cu), carbon (C) and / or nitrogen (N).For example, the free magnetic transition layer 461 may include CoFe and / or NiFe, and may further include boron (B). Moreover, the free magnetic transition layer 461 may further include at least one selected from non-magnetic elements including titanium (Ti), aluminum (Al), silicon (Si), magnesium (Mg), and / or tantalum (Ta). The content of the selected non-magnetic element in the free magnetic transition layer 461 may be in a range of about 1% to about 15% atomic percent.An upper exchange coupling control layer 463 may be disposed on the free magnetic transition layer 461. The exchange coupling control upper layer 463 may include a material having a large exchange coupling constant, e.g., a ferromagnetic material, or a material that contains the orientation and vertical anisotropy of an adjacent magnetic substance, e.g., a nonmagnetic metal. For example, the exchange coupling upper control layer 463 may include at least one selected from the group consisting of iron (Fe), cobalt (Co), and / or nickel (Ni). For example, the exchange coupling upper control layer 463 may include at least one selected from the group consisting of titanium (Ti), chromium (Cr), ruthenium (Ru), copper (Cu), magnesium (Mg), zinc (Zn), aluminum (Al), tantalum (Ta), palladium (Pd), and / or platinum (Pt). In some embodiments, the exchange coupling upper control layer 463 may further include an oxidation layer contacting the exchange coupling upper control layer 463. The oxidation layer may be an oxide of some of the exchange coupling control top layer 463.The upper free magnetic layer 466 may include a single magnetic layer or a plurality of magnetic layers. For example, the upper free magnetic layer 466 may include a free ferromagnetic layer, a free nonmagnetic layer, and a second free ferromagnetic layer, i.e., an artificial antiferromagnetic (SAF) layer, which are sequentially stacked on the upper exchange coupling control layer 463. The upper free magnetic layer 466 may include magnetic layers having a variable magnetization direction in various shapes.A capping layer 470 is disposed on the upper free magnetic layer 466. The capping layer may include at least one selected from the group consisting of tantalum (Ta), aluminum (Al), copper (Cu), gold (Au), silver (Ag), titanium (Ti), tantalum nitride (TaN), and / or titanium nitride (TiN).Referring to FIG. 10, an exemplary method of forming a magnetic memory device according to the fourth embodiments of the inventive concept will be described. Further discussions of elements described above may be omitted for the sake of brevity.Referring to FIG. 10, a bottom electrode 420 and a seed layer 430 are formed on a substrate 410. The seed layer 430 may include metals having an hcp lattice or a kfz lattice. For example, the seed layer 430 may include at least one selected from the group consisting of ruthenium (Ru), titanium (Ti), palladium (Pd), gold (Au), silver (Ag), copper (Cu), and / or aluminum (Al). The seed layer 430 may be formed with a relatively small thickness. For example, the seed layer 430 may be formed to have a thickness in a range from about 1.0 nm (nanometers) to about 10.0 nm (nanometers).A vertically magnetic reference layer 442 is formed on the seed layer 430. The vertically magnetic reference layer 442 may include a material having a high dependence on the seed layer 430. For example, the crystal structure of the vertical magnetic reference layer 442 may be aligned with the crystal structure of the seed layer 430. For example, the vertically magnetic reference layer 442 may grow along the C-axis of the seed layer 430. Accordingly, the vertically magnetic reference layer 442, which grows as a seed using the seed layer 430, may be formed by a relatively low temperature method.For example, the vertical magnetic reference layer 442 may include cobalt (Co) and / or platinum (Pt). The vertically magnetic reference layer 442 may include an ordered alloy or an disordered alloy according to the cobalt (Co) and platinum (Pt) content. For example, the vertically magnetic reference layer 442 formed using the seed layer 330 as a seed may be deposited at room temperature.A lower exchange coupling control layer 444 may be formed on the vertical magnetic layer 442. The lower exchange coupling control layer 444 may include a ferromagnetic metal having a large exchange coupling constant, for example, at least one selected from metals including iron (Fe), cobalt (Co), and / or nickel (Ni). Conversely, the exchange coupling lower control layer 444 can increase the surface magnetic anisotropy of an adjacent magnetic substance. For example, the lower exchange coupling control layer 444 may include a non-magnetic material, e.g., a non-magnetic material element or a transition metal. The lower exchange coupling control layer 444 may include at least one selected from the group consisting of titanium (Ti), chromium (Cr), ruthenium (Ru), rhodium (Rh), copper (Cu), magnesium (Mg), zinc (Zn), aluminum (Al), tantalum (Ta), palladium (Pd), and / or platinum (Pt).In some examples, the surface of the lower exchange coupling control layer 444 may be oxidized. A method of oxidizing may include introducing a minute amount of oxygen into a chamber in which a product in which the vertical magnetic layer 442 has been formed is loaded before formation of the lower exchange coupling control layer 444, or forming an oxidation layer by introducing a minute amount of oxygen into the chamber after formation of the lower exchange coupling control layer 444 with an atomic layer thickness and then forming the remaining lower exchange coupling control layer 444.A reference magnetic transition layer 448 may be formed on the lower exchange coupling control layer 444. The vertical anisotropy of the reference magnetic transition layer 448 may be increased by the reference vertical magnetic layer 442 and / or the exchange coupling lower control layer 444.A tunnel barrier 450 is formed on the reference magnetic junction layer 448. The tunnel barrier 450 may include at least one selected from the group consisting of magnesium (Mg), titanium (Ti), aluminum (Al), an oxide of magnesium zinc (MgZn), and / or magnesium boron (MgB), and / or a nitride of titanium (Ti) and / or vanadium (V). Conversely, the tunnel barrier (450) may include a plurality of layers. For example, tunnel barrier 450 may include magnesium (Mg) / magnesium oxide (MgO), magnesium oxide (MgO) / magnesium (Mg), and / or magnesium (Mg) / magnesium oxide (MgO) / magnesium (Mg). In an embodiment, the tunnel barrier 450 may have a NaCl (body centered cubic lattice structure) type structure. For example, tunnel barrier 450 may include magnesium oxide (MgO).A free magnetic transition layer 461 is formed on the tunnel barrier 450. The free magnetic transition layer 461 may have a relatively low saturation magnetization. The free magnetic transition layer 461 may further include a non-magnetic material. The free magnetic transition layer 461 may be formed in an amorphous state.A lower exchange coupling control layer 463 may be formed on the free magnetic transition layer 461. In an embodiment, the free magnetic transition layer 461 may include a magnetic material having a large exchange coupling constant. Accordingly, as the exchange coupling between the free magnetic transition layer 461 and an upper reference magnetic layer 466, which will be described below, increases, the vertical anisotropy of the free magnetic transition layer 461 can be increased. In particular, when the exchange coupling control layer is formed on the free magnetic transition layer 461, the crystal structure of the free magnetic transition layer 461 cannot be crystallized into the crystal structure of the upper free magnetic layer 466 which will be described later, but it may be aligned with the crystal structure of the tunnel barrier 450. When the free magnetic transition layer 461 aligns with the crystal structure of the tunnel barrier 450, the magneto-resistance ratio of a magnetic tunnel clock including the free magnetic transition layer 461 can be increased. In an embodiment, the interface between the exchange coupling upper control layer 463 and the free magnetic transition layer 461 may be oxidized. A method of oxidizing may be performed by introducing a minute amount of oxygen into a chamber into which the substrate 410 on which the upper free magnetic transition layer 461 has been formed has been introduced after formation of the upper free magnetic transition layer 461, or by forming an oxide by introducing a minute amount of oxygen into the chamber after formation of the exchange coupling control layer 463 having an atomic layer thickness and then formation of the remaining exchange coupling control layer 463.An upper free magnetic layer 466 may be formed on the upper exchange coupling control layer 463. The upper free magnetic layer 466 may include a single layer containing a ferromagnetic material or a plurality of layers containing the single layer. In one embodiment, the upper free magnetic layer 466 may include a ferromagnetic layer-antiferromagnetic layer-ferromagnetic layer structure.A capping layer 470 may be formed on the exchange coupling upper control layer 463. The capping layer 470 may include at least one selected from the group consisting of tantalum (Ta), aluminum (Al), copper (Cu), gold (Au), silver (Ag), titanium (Ti), tantalum nitride (TaN), and / or titanium nitride (TiN).In some examples, a magnetic memory device may include a tunnel barrier on a substrate, first and second magnetic junction layers, and a non-magnetic layer. The first magnetic junction layer may contact a surface of the tunnel barrier. A first vertical magnetic layer may be separated from the tunnel barrier by the first magnetic junction layer. The second magnetic junction layer may contact the other surface of the tunnel junction and a second vertical magnetic layer may be separated from the tunnel barrier by the second magnetic junction layer. The non-magnetic layer may be between the first transition magnetic layer and the first vertical magnetic layer.In other examples, the magnetization directions of the first vertical magnetic layer and the second vertical magnetic layer may be vertical to the plane of the substrate when the magnetic memory device operates.In other examples, another non-magnetic layer may be disposed between the second transition magnetic layer and the second vertical magnetic layer.In other examples, the first transition magnetic layer and / or the second transition magnetic layer may have a first crystal structure, while the first vertical magnetic layer and / or the second vertical magnetic layer may have a second crystal structure different from the first crystal structure.In other examples, the crystal plane of the tunnel barrier at the interface between the tunnel barrier and the first junction may be identical to the crystal plane of the first junction magnetic layer at the interface. The first crystal structure may be a NaCl type crystal structure or a body centered cubic crystal structure, and the crystal planes may be a (001) crystal plane.In further examples, the second crystal structure may be an L10 crystal structure, a face centered cubic crystal structure, or a hexagonal close-packed (hcp) lattice.In further examples, the first vertical magnetic layer and / or the second vertical magnetic layer may be a RE-TM (rare earth transition metal) alloy.In further examples, the first vertical magnetic layer and / or the second magnetic layer may include multiple alternating stacked non-magnetic metal layers and ferromagnetic metal layers, wherein the ferromagnetic metal layers may have a thickness of one to more atoms.In further examples, the first magnetic transition layer and / or the second magnetic transition layer may include a magnetic alloy material including at least one selected from the group consisting of cobalt (Co), iron (Fe), and nickel (Ni), and the magnetic alloy substance may further include a non-magnetic element.In some examples, the non-magnetic layer may have a thickness in a range from about 0.2 nm (nanometers) to about 2.0 nm (nanometers).In other embodiments, the non-magnetic layer may include at least one selected from non-magnetic metals. The non-magnetic metal may be at least one selected from non-magnetic transition metals.In other examples, the first vertical magnetic layer and the first transition magnetic layer may be exchange-coupled to each other through the non-magnetic layer.In other examples, the non-magnetic layer may further include a metal compound layer contacting the top surface and / or the bottom surface of the non-magnetic layer, and the metal compound layer may include at least one selected from the group consisting of metal oxide, metal nitride, and metal oxynitride.In other examples of the inventive concept, magnetic storage devices may include a tunnel barrier on a substrate, a free magnetic layer contacting one surface of the tunnel barrier and having a plane parallel to the plane of the substrate, and a reference magnetic layer contacting the other surface of the tunnel barrier and having a plane parallel to the plane of the substrate. The free magnetic layer and the reference magnetic layer may contain iron (Fe), and the iron content of the free magnetic layer may be equal to or more than that of the reference magnetic layer.In some examples, the iron (Fe) content of the free magnetic layer may be in a range from about 40% to about 60% atomic percent.In further examples, the free magnetic layer and / or the reference magnetic layer may further include at least one selected from Co and Ni.In other examples, the free magnetic layer and / or the reference magnetic layer may further include a non-magnetic element.In other examples, the free magnetic layer and the reference magnetic layer may have magnetization directions vertical (perpendicular) to the plane / surface of the substrate when the magnetic storage device is operating.In other examples, the free magnetic layer and the reference magnetic layer may have magnetization directions parallel to the plane / surface of the substrate when the magnetic storage device is operating.In other examples of the inventive concept, magnetic memory devices may include a substrate. A first magnetic substance, a tunnel barrier, and a second magnetic substance may be sequentially stacked on the substrate. The first magnetic substance may include a first vertical magnetic layer adjacent to the substrate and may have a hexagonal close-packed (hcp) lattice structure.In some examples, the C-axis of the hexagonal close-packed lattice may be substantially vertical to the plane of the substrate.In other examples, the C-axis may be an axis at which the first vertical magnetic layer may be easily magnetized.In other examples, the magnetic memory device may further include a seed layer including the hcp lattice between the substrate and the first vertical magnetic layer.In other examples, the second magnetic substrate may further include a second vertical magnetic layer having a hexagonal close-packed lattice structure.In other examples, the first magnetic substance may include a first magnetic junction layer adjacent to the tunnel barrier on the first vertical magnetic layer and the second magnetic substance may include a second magnetic junction layer adjacent to the tunnel barrier below the second vertical magnetic layer.In further examples, the second magnetic transition layer and the first magnetic transition layer may include a soft magnetic material.In other examples, the magnetic storage device may include an exchange-coupled control layer between the first vertical magnetic layer and the first magnetic transition layer and / or between the second vertical magnetic layer and the second magnetic transition layer.In further examples, the exchange-coupled control layer may include at least one selected from metal elements including transition metal elements.In further examples, the replacement coupled control layer may further include an oxide layer formed by oxidation of the surface of the replacement coupled control layer.In alternative examples, the second magnetic substance may further include multiple alternating stacked non-magnetic layers and ferromagnetic layers on the second vertical magnetic layer. The ferromagnetic layers may have the thickness of an atomic layer.In alternative examples, the first vertical magnetic layer may include a disordered cobalt-platinum alloy having a platinum content in a range of about 10% to 45% atomic percent.In alternative embodiments, the first vertical magnetic layer may include Co 3 Pt.In alternative examples, the first vertical magnetic layer may further include at least one selected from the group consisting of boron (B), chromium (Cr), and copper (Cu).In alternative examples, the tunnel barrier may include at least one selected from the group consisting of magnesium (Mg), titanium (Ti), aluminum (Al), an oxide of magnesium zinc (MgZn) and / or magnesium boron (MgB) and / or a nitride of titanium (Ti) and / or vanadium (V).In alternative examples, the magnetic storage device may further include a capping layer on the second magnetic substance. The capping layer may include at least one selected from the group consisting of tantalum (Ta), aluminum (Al), copper (Cu), gold (Au), silver (Ag), titanium (Ti), tantalum nitride (TaN), and / or titanium nitride (TiN).In alternative examples, the current may flow in a direction substantially vertical to the plane of the substrate when the magnetic storage device is in operation.In alternative examples, the magnetization directions of the second magnetic layer and the first magnetic layer may be substantially vertical to the plane of the substrate.In some examples, a magnetic storage device may include a first vertical magnetic layer, a non-magnetic layer on the first vertical magnetic layer, and a first magnetic transition layer on the non-magnetic layer, the non-magnetic layer being between the first vertical magnetic layer and the first magnetic transition layer. A tunnel barrier may be on the first magnetic junction layer, the first magnetic junction layer being between the non-magnetic layer and the tunnel barrier. A second magnetic junction layer may be on the tunnel barrier, the tunnel barrier being between the first and second magnetic junction layers. A second vertical magnetic layer may be on the second magnetic junction layer, the second magnetic junction layer being between the tunnel barrier and the second vertical magnetic layer.In some further examples, a magnetic storage device may include a free magnetic layer including iron (Fe), a tunnel barrier on the free magnetic layer, and a reference magnetic layer including iron (Fe) on the tunnel barrier. The tunnel barrier may be between the free magnetic layer and the reference magnetic layer. An iron concentration of the free magnetic layer may be at least as large as an iron concentration of the reference magnetic layer.In other examples, a magnetic storage device may include a substrate, a first magnetic substance on the substrate, a tunnel barrier on the first magnetic substance, and a second magnetic substance on the tunnel barrier. The first magnetic substance may include a vertical magnetic layer adjacent to the substrate and having a hexagonal close-packed (hcp) lattice structure. The magnetic substance may be between the substrate and the tunnel barrier, wherein the tunnel barrier may be between the first and second magnetic substances.In some examples of the inventive concept, when a non-magnetic layer is interposed between a vertical magnetic layer and a magnetic junction layer, a magnetic resistance ratio and a vertical magnetization characteristic of a magnetic tunnel junction including the magnetic junction layer can be improved. In addition, during the operation of the magnetic storage device, switching characteristics can be improved by a free magnetic layer and a reference magnetic layer each having a different content of iron. Accordingly, the reliability of the magnetic storage device can be improved.In further examples of the inventive concept, a hexagonal close-packed (hcp) grid with an axis which is vertical to the plane of the substrate 100 and easily magnetizable may have. Accordingly, the directions of the spins of electrons can be arranged to a perpendicular direction with respect to the substrate. Thereby, a magnetic resistance ratio of a magnetic tunnel junction can be improved. In addition, the switching current of the magnetic storage device including a magnetic tunnel junction can be reduced.

Claims

A magnetic storage device comprising: a first vertical magnetic layer (123) having a first vertical magnetization direction; a non-magnetic layer (130) on the first vertical magnetic layer (123); a first magnetic transition layer (141) on the non-magnetic layer (130), the non-magnetic layer (130) being between the first vertical magnetic layer (123) and the first magnetic transition layer (141); a tunnel barrier (145) on the first magnetic transition layer (141), the first magnetic transition layer (141) being between the non-magnetic layer (130) and the tunnel barrier (145); a second magnetic transition layer (149) on the tunnel barrier (145), the tunnel barrier (145) being between the first (141) and the second magnetic transition layer (149); and a second vertical magnetic layer (163) having a second vertical magnetization direction on the second transition magnetic layer (149), wherein the second transition magnetic layer (149) is interposed between the tunnel barrier (145) and the second vertical magnetic layer (163), wherein the first and second vertical magnetization directions are perpendicular to a plane of the tunnel barrier (145), and wherein an iron content in the second transition magnetic layer (149) is greater than that in the first transition magnetic layer (141).The magnetic storage device of claim 1, wherein the non-magnetic layer (130) is a first non-magnetic layer, and wherein the device further comprises: a second non-magnetic layer (150) between the second transition magnetic layer (149) and the second vertical magnetic layer (163).The magnetic storage device according to claim 1, wherein the first transition magnetic layer (141) and / or the second transition magnetic layer (149) has a first crystal structure, and wherein the first vertical magnetic layer (123) and / or the second vertical magnetic layer (163) has a second crystal structure different from the first crystal structure.The magnetic storage device according to claim 3, wherein a crystal plane of the tunnel barrier (145) at an interface between the tunnel barrier (145) and the first magnetic junction layer (141) and a crystal plane of the first magnetic junction layer (141) at the interface between the tunnel barrier (145) and the first magnetic junction layer (141) are the same.The magnetic memory device according to claim 4, wherein the first crystal structure is a body centered cubic crystal structure, and the crystal plane is a (001) crystal plane.The magnetic memory device according to claim 3, wherein the second crystal structure is an L10 crystal structure or a hexagonal close-packed lattice.The magnetic storage device according to claim 1, wherein the first vertical magnetic layer (123) and / or the second vertical magnetic layer (163) include non-magnetic metal layers (121, 161) and ferromagnetic metal layers (122, 162) stacked in multiple alternation, and the ferromagnetic metal layers (122, 162) have a thickness of one to more atoms.The magnetic storage device according to claim 1, wherein the first magnetic transition layer (141) and / or the second magnetic transition layer (149) includes at least one selected from the group consisting of cobalt and nickel, and a non-magnetic element.The magnetic storage device according to claim 1, wherein the first vertical magnetic layer (123) and / or the second vertical magnetic layer (163) comprises a rare earth-transition metal alloy.The magnetic memory device of claim 1, wherein the non-magnetic layer (130) has a thickness in a range from about 0.2 nanometers to about 2.0 nanometers.The magnetic storage device of claim 1, wherein the non-magnetic layer (130) comprises a non-magnetic metal.The magnetic storage device of claim 1, wherein the non-magnetic layer (130) comprises a non-magnetic transition metal.The magnetic storage device according to claim 1, wherein the first vertical magnetic layer (123) and the first transition magnetic layer (141) are exchange-coupled by the non-magnetic layer (130).The magnetic memory device according to claim 1, wherein the non-magnetic layer (130) includes a metal compound layer having at least one selected from the group consisting of a metal oxide, a metal nitride, and a metal oxynitride.

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