Magnetic memory device

A magnetic memory device includes a reference magnetic structure, a free magnetic structure, and a tunnel barrier pattern between the reference magnetic structure and the free magnetic structure. The reference magnetic structure includes a first pinned pattern, a second pinned pattern between the first pinned pattern and the tunnel barrier pattern, and an exchange coupling pattern between the first and the second pinned pattern. The second pinned pattern includes a first magnetic pattern adjacent the exchange coupling pattern, a second magnetic pattern adjacent the tunnel barrier pattern, a third magnetic pattern between the first and the second magnetic pattern, a first non-magnetic pattern between the first and the third magnetic pattern, and a second non-magnetic pattern between the second and the third magnetic pattern. The first non-magnetic pattern has a different crystal structure from the second non-magnetic pattern, and at least a portion of the third magnetic pattern is amorphous.

REFERENCE TO PRIORITY APPLICATION

This U.S. non-provisional patent application claims priority under 35 U.S.C. § 119 to Korean Patent Application No. 10-2016-0143509, filed on Oct. 31, 2016, the disclosure of which is incorporated herein in its entirety by reference.

BACKGROUND

Embodiments of the inventive concepts relate to semiconductor memory devices, and more particularly, to a magnetic memory devices.

Due to increasing demand for electronic devices with a high speed and/or low power consumption, semiconductor devices may require faster operating speeds and/or lower operating voltages. Magnetic memory devices have been suggested to satisfy such requirements. For example, magnetic memory devices can provide technical advantages, such as reduced latency and/or non-volatility. As a result, magnetic memory devices may be used in next-generation memory devices.

Generally, a magnetic memory device may include a magnetic tunnel junction pattern (MTJ). A magnetic tunnel junction pattern may include two magnetic layers and an insulating layer interposed the two magnetic layers. A resistance value of the magnetic tunnel junction pattern may vary depending on magnetization directions of the two magnetic layers. For example, the resistance value of the magnetic tunnel junction pattern may be higher when magnetization directions of the two magnetic layers are anti-parallel to each other than when they are parallel to each other. Data can be stored into and/or read out from the magnetic tunnel junction pattern by using a difference between these resistance values.

SUMMARY

According to some embodiments of the inventive concepts, a magnetic memory device may include a reference magnetic structure and a free magnetic structure on a substrate, and a tunnel barrier pattern between the reference magnetic structure and the free magnetic structure. The reference magnetic structure includes a first pinned pattern, a second pinned pattern between the first pinned pattern and the tunnel barrier pattern, and an exchange coupling pattern between the first pinned pattern and the second pinned pattern. The second pinned pattern includes a first magnetic pattern adjacent the exchange coupling pattern, a second magnetic pattern adjacent the tunnel barrier pattern, a third magnetic pattern between the first magnetic pattern and the second magnetic pattern, a first non-magnetic pattern between the first magnetic pattern and the third magnetic pattern, and a second non-magnetic pattern between the second magnetic pattern and the third magnetic pattern. The first non-magnetic pattern has a different crystal structure from the second non-magnetic pattern, and at least a portion of the third magnetic pattern is amorphous.

According to some embodiments of the inventive concepts, a magnetic memory device may include a reference magnetic structure and a free magnetic structure on a substrate, and a tunnel barrier pattern between the reference magnetic structure and the free magnetic structure. The reference magnetic structure includes a first pinned pattern, a second pinned pattern between the first pinned pattern and the tunnel barrier pattern, and an exchange coupling pattern between the first pinned pattern and the second pinned pattern. The second pinned pattern includes a first magnetic pattern adjacent the exchange coupling pattern, a second magnetic pattern adjacent the tunnel barrier pattern, a third magnetic pattern between the first magnetic pattern and the second magnetic pattern, a first non-magnetic pattern between the first magnetic pattern and the third magnetic pattern, and a second non-magnetic pattern between the second magnetic pattern and the third magnetic pattern. The first non-magnetic pattern includes a different material from the second non-magnetic pattern, and at least a portion of the third magnetic pattern is amorphous.

According to some embodiments of the inventive concepts, a magnetic memory device may include a magnetic tunnel junction (MTJ) pattern that may include a reference magnetic structure, a free magnetic structure, and a tunnel barrier pattern therebetween. The reference magnetic structure may include first and second pinned patterns and an exchange coupling pattern therebetween. The second pinned pattern may include a first magnetic pattern, a first non-magnetic pattern, a second non-magnetic pattern, and a second magnetic pattern that are sequentially stacked between the exchange coupling pattern and the tunnel barrier pattern. The first non-magnetic pattern and the first magnetic pattern may include a same crystal structure. The second non-magnetic pattern may include a different crystal structure than the first non-magnetic pattern. The second pinned pattern may further include a third magnetic pattern, which may be at least partially amorphous, between the first and second non-magnetic patterns.

DETAILED DESCRIPTION

Embodiments of the inventive concepts will now be described more fully with reference to the accompanying drawings, in which embodiments are shown. Embodiments of the inventive concepts may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concepts of embodiments to those of ordinary skill in the art.

FIG. 1is a circuit diagram illustrating a memory cell array of a magnetic memory device according to embodiments of the inventive concepts.FIG. 2is a circuit diagram illustrating a unit memory cell of a magnetic memory device according to embodiments of the inventive concepts.

Referring toFIG. 1, the memory cell array10may include a plurality of word lines WL0-WL3, a plurality of bit lines BL0-BL3and unit memory cells MC. The unit memory cells MC may be two or three dimensionally arranged. The word lines WL0-WL3and the bit lines BL0-BL3may be provided to cross each other, and each of the unit memory cells MC may be provided at a corresponding one of intersections between the word lines WL0-WL3and bit lines BL0-BL3. Each of the word lines WL0-WL3may be connected to a plurality of the unit memory cells MC. The unit memory cells MC connected to each of the word lines WL0-WL3may be connected to the bit lines BL0-BL3, respectively. The unit memory cells MC connected to each of the bit lines BL0-BL3may be connected to the word lines WL0-WL3, respectively. Accordingly, the unit memory cells MC connected to the word line WL may be connected to a read and write circuit through the bit lines BL0-BL3, respectively.

Referring toFIG. 2, the unit memory cell MC may include a memory element ME and a select element SE. The memory element ME may be provided between the bit line BL and the select element SE. The select element SE may be provided between the memory element ME and the word line WL. The memory element ME may be a variable resistance device whose resistance can be switched to one of at least two states by an electric pulse applied thereto.

The memory element ME may be formed to have a layered structure, whose electric resistance can be changed by a spin transfer process using an electric current passing therethrough. For example, the memory element ME may have a layered structure configured to exhibit a magnetoresistance property, and may include at least one ferromagnetic material and/or at least one antiferromagnetic material.

The select element SE may be configured to selectively control a flow of electric charges passing through the memory element MC. For example, the select element SE may be one of a diode, a p-n-p bipolar transistor, an n-p-n bipolar transistor, an n-channel metal-oxide-semiconductor field effect transistor (NMOSFET) and a p-channel metal-oxide-semiconductor field effect transistor (PMOSFET). When the select element SE is a three-terminal switching device, such as a bipolar transistor or a MOSFET, an additional interconnection line may be connected to the select element SE.

The memory element ME may include a first magnetic structure MS1, a second magnetic structure MS2and a tunnel barrier TBR interposed therebetween. The first magnetic structure MS1, the second magnetic structure MS2and the tunnel barrier TBR may constitute or define a magnetic tunnel junction MTJ. The first and second magnetic structures MS1and MS2may respectively include at least one magnetic layer formed of a magnetic material. The memory element ME may further include a bottom electrode BE and a top electrode TE. The bottom electrode BE may be interposed between the first magnetic structure MS1and the select element SE, and the top electrode TE may be interposed between the second magnetic structure MS2and the bit line BL.

FIG. 3is a cross-sectional view illustrating a magnetic memory device according to some embodiments of the inventive concepts.FIG. 4is an enlarged view illustrating a reference magnetic structure ofFIG. 3.FIG. 5Ais a diagram illustrating an arrangement of atoms in a first magnetic pattern and a first non-magnetic pattern ofFIG. 3when viewed in a plan view.FIG. 5Bis a diagram illustrating an arrangement of atoms in a second magnetic pattern and a second non-magnetic pattern ofFIG. 3when viewed in a plan view.

Referring toFIG. 3, a lower interlayer insulating layer102may be provided on a substrate100. The substrate100may be a semiconductor substrate including silicon (Si), silicon-on-insulator (SOI), silicon germanium (SiGe), germanium (Ge), or gallium arsenide (GaAs). Selection elements such, for example, field effect transistors or diodes may be provided on the substrate100, and the lower interlayer insulating layer102may be provided to extend on or cover the selection elements. The lower interlayer insulating layer102may include oxide, nitride and/or oxynitride.

A lower contact plug104may be provided in the lower interlayer insulating layer102. The lower contact plug104may penetrate the lower interlayer insulating layer102and may be electrically coupled to a terminal of a corresponding one of the selection elements. The lower contact plug104may include at least one of doped semiconductor materials (e.g., doped silicon), metals (e.g., tungsten, titanium and/or tantalum), conductive metal nitrides (e.g., titanium nitride, tantalum nitride and/or tungsten nitride) or metal-semiconductor compounds (e.g., metal silicide).

A bottom electrode BE may be provided on the lower interlayer insulating layer102. The bottom electrode BE may be electrically coupled to the lower contact plug104. The bottom electrode BE may include a conductive material. As an example, the bottom electrode BE may include conductive metal nitrides, such as titanium nitride and/or tantalum nitride.

A reference magnetic structure RMS and a free magnetic structure FMS may be stacked on the lower interlayer insulating layer102. A tunnel barrier pattern TBR may be provided between the reference magnetic structure RMS and the free magnetic structure FMS. In some embodiments, the reference magnetic structure RMS may be provided between the bottom electrode BE and the tunnel barrier pattern TBR.

The reference magnetic structure RMS may include at least one fixed layer having a fixed magnetization direction, and the free magnetic structure FMS may include at least one free layer having a switchable magnetization direction. The reference magnetic structure RMS, the free magnetic structure FMS and the tunnel barrier pattern TBR may constitute or define a magnetic tunnel junction pattern MTJ. The magnetization directions of the fixed layer and the free layer may be substantially perpendicular to an interface between the tunnel barrier pattern TBR and the free magnetic structure FMS. That is, the magnetic tunnel junction pattern MTJ may be a perpendicular magnetization-type magnetic tunnel junction pattern.

A top electrode TE may be provided on the magnetic tunnel junction pattern MTJ. The magnetic tunnel junction pattern MTJ may be interposed between the bottom electrode BE and the top electrode TE. In some embodiments, the free magnetic structure FMS may be provided between the tunnel barrier pattern TBR and the top electrode TE. The bottom electrode BE, the magnetic tunnel junction pattern MTJ and the top electrode TE may be provided to have vertically-aligned sidewalls. The top electrode TE may include a conductive material. As an example, the top electrode TE may include at least one of tantalum (Ta), aluminum (Al), copper (Cu), gold (Au), silver (Ag), or titanium (Ti).

The reference magnetic structure RMS may include a synthetic antiferromagnetic (SAF) structure. As an example, the reference magnetic structure RMS may include a first pinned pattern110, a second pinned pattern130and an exchange coupling pattern120interposed between the first pinned pattern110and the second pinned pattern130. The second pinned pattern130may be provided between the first pinned pattern110and the tunnel barrier pattern TBR. The exchange coupling pattern120may couple the first pinned pattern110to the second pinned pattern130in such a way that a magnetization direction110mof the first pinned pattern110is anti-parallel to a magnetization direction130mof the second pinned pattern130. Thus, magnetic fields generated by the first and second pinned patterns110and130may offset each other to reduce or minimize a net magnetic field of the reference magnetic structure RMS. As a result, an influence of the magnetic field of the reference magnetic structure RMS on the free magnetic structure FMS can be reduced or minimized. For example, the exchange coupling pattern120may include ruthenium (Ru).

The first pinned pattern110may include perpendicular magnetic materials (e.g., CoFeTb, CoFeGd, CoFeDy), perpendicular magnetic materials with L10structure, CoPt-based materials with hexagonal-close-packed lattices and/or perpendicular magnetic structures. The L10perpendicular magnetic material may include at least one of L10FePt, L10FePd, L10CoPd, or L10CoPt. The perpendicular magnetic structure may include magnetic layers and non-magnetic layers that are alternatively and repeatedly stacked. For example, the perpendicular magnetic structure may include at least one of (Co/Pt)n, (CoFe/Pt)n, (CoFe/Pd)n, (Co/Pd)n, (Co/Ni)n, (CoNi/Pt)n, (CoCr/Pt)n or (CoCr/Pd)n, where n is the number of stacked pairs of the layers.

Referring toFIGS. 3 and 4, the second pinned pattern130may include a first magnetic pattern140, a second magnetic pattern142, a third magnetic pattern144, a first non-magnetic pattern150and a second non-magnetic pattern152. The first magnetic pattern140may be adjacent the exchange coupling pattern120. The second magnetic pattern142may be adjacent the tunnel barrier pattern TBR. The third magnetic pattern144may be provided between the first magnetic pattern140and the second magnetic pattern142. The first non-magnetic pattern150may be provided between the first magnetic pattern140and the third magnetic pattern144. The second non-magnetic pattern152may be provided between the second magnetic pattern142and the third magnetic pattern144.

The first magnetic pattern140may be in contact with the exchange coupling pattern120. The first magnetic pattern140may be anti-ferromagnetically coupled to the first pinned pattern110through the exchange coupling pattern120. The exchange coupling pattern120may couple the first pinned pattern110to the first magnetic pattern140in such a way that the magnetization direction110mof the first pinned pattern110is anti-parallel to a magnetization direction140mof the first magnetic pattern140. That is, the magnetization direction140mof the first magnetic pattern140may be anti-parallel to the magnetization direction110mof the first pinned pattern110.

The first magnetic pattern140may have a hexagonal close-packed (HCP) crystal structure or a face centered cubic (FCC) crystal structure. When the first magnetic pattern140has the hexagonal close-packed (HCP) crystal structure, the first magnetic pattern140may be provided to have a (0001) plane parallel to the interface between the tunnel barrier pattern TBR and the free magnetic structure FMS. When the first magnetic pattern140has the face centered cubic (FCC) crystal structure, the first magnetic pattern140may be provided to have a (111) plane parallel to the interface between the tunnel barrier pattern TBR and the free magnetic structure FMS. In some embodiments, the interface between the tunnel barrier pattern TBR and the free magnetic structure FMS may be substantially parallel to a top surface of the substrate100. Thus, a (0001) plane of the first magnetic pattern140having a hexagonal close-packed (HCP) crystal structure, or a (111) plane of the first magnetic pattern140having a face centered cubic (FCC) crystal structure may be substantially parallel to the top surface of the substrate100.

Referring toFIG. 5A, when viewed in a plan view (e.g., when viewed in a plan view parallel to the top surface of the substrate100), atoms in the first magnetic pattern140may be arranged to have a 6-fold symmetry. A line L1shown inFIG. 5Ais a virtual line representing a crystal plane lattice, a line S1is a virtual line representing an atomic arrangement of the 6-fold symmetry. The first magnetic pattern140may include a magnetic material that enhances antiferromagnetic coupling with the first pinned pattern110. For example, the first magnetic pattern140may include at least one of cobalt (Co) or nickel (Ni).

The first non-magnetic pattern150may have a hexagonal close-packed (HCP) crystal structure or a face centered cubic (FCC) crystal structure. When the first non-magnetic pattern150has the hexagonal close-packed (HCP) crystal structure, the first non-magnetic pattern150may be provided to have a (0001) plane parallel to the interface between the tunnel barrier pattern TBR and the free magnetic structure FMS. When the first non-magnetic pattern150has the face centered cubic (FCC) crystal structure, the first non-magnetic pattern150may be provided to have a (111) plane parallel to the interface between the tunnel barrier pattern TBR and the free magnetic structure FMS. In some embodiments, the interface between the tunnel barrier pattern TBR and the free magnetic structure FMS may be substantially parallel to the top surface of the substrate100. Thus, a (0001) plane of the first non-magnetic pattern150having a hexagonal close-packed (HCP) crystal structure, or a (111) plane of the first non-magnetic pattern150having a face centered cubic (FCC) crystal structure may be substantially parallel to the top surface of the substrate100. As described with reference toFIG. 5A, when viewed in a plan view (e.g., when viewed in a plan view parallel to the top surface of the substrate100), atoms in the first non-magnetic pattern150may be arranged to have 6-fold symmetry. That is, when viewed in a plan view, the arrangement of atoms in the first non-magnetic pattern150may have the same symmetry as the arrangement of atoms in the first magnetic pattern140. The first non-magnetic pattern150may include at least one of Ir, Rh, Pd, Ag, Ru, Y, Sc, Zr, Hf, Ti or Re.

The second magnetic pattern142may be in contact with the tunnel barrier pattern TBR. Such a contact between the second magnetic pattern142and the tunnel barrier pattern TBR may induce magnetic anisotropy, allowing the second magnetic pattern142to have a perpendicular magnetization property. The second magnetic pattern142may be ferromagnetically coupled to the first magnetic pattern140. That is, a magnetization direction142mof the second magnetic pattern142may be parallel to the magnetization direction140mof the first magnetic pattern140. The magnetization directions130mof the second pinned pattern130may be determined by the magnetization directions140mand142mof the first and second magnetic patterns140and142. A crystal structure of the second magnetic pattern142may be different from crystal structures of the first magnetic pattern140and the first non-magnetic pattern150. The second magnetic pattern142may have a body centered cubic (BCC) crystal structure. A (001) plane of the second magnetic pattern142having the body centered cubic (BCC) crystal structure may be provided to be parallel to the interface between the tunnel barrier pattern TBR and the free magnetic structure FMS. In some embodiments, the interface between the tunnel barrier pattern TBR and the free magnetic structure FMS may be substantially parallel to the top surface of the substrate100. Thus, a (001) plane of the second magnetic pattern142having a body centered cubic (BCC) crystal structure may be substantially parallel to the top surface of the substrate100.

Referring toFIG. 5B, when viewed in a plan view (e.g., when viewed in a plan view parallel to the top surface of the substrate100), atoms in the second magnetic pattern142may be arranged to have a 4-fold symmetry. A line L2shown inFIG. 5Bis a virtual line representing a crystal plane lattice, a line S2is a virtual line representing an atomic arrangement of the 4-fold symmetry. For example, the second magnetic pattern142may include iron (Fe). The second magnetic pattern142may include a magnetic material that induces magnetic anisotropy at an interface between the second magnetic pattern142and the tunnel barrier pattern TBR. For example, the second magnetic pattern142may include cobalt-iron-boron (CoFeB).

The second non-magnetic pattern152may have the same crystal structure as the second magnetic pattern142. The second non-magnetic pattern152may have a body centered cubic (BCC) crystal structure. A (001) plane of the second non-magnetic pattern152having the body centered cubic (BCC) crystal structure may be provided to be parallel to the interface between the tunnel barrier pattern TBR and the free magnetic structure FMS. In some embodiments, the interface between the tunnel barrier pattern TBR and the free magnetic structure FMS may be substantially parallel to the top surface of the substrate100. Thus, a (001) plane of the second non-magnetic pattern152having a body centered cubic (BCC) crystal structure may be substantially parallel to the top surface of the substrate100. As described with reference toFIG. 5B, when viewed in a plan view (e.g., when viewed in a plan view parallel to the top surface of the substrate100), atoms in the second non-magnetic pattern152may be arranged to have the 4-fold symmetry. That is, an arrangement of atoms in the second non-magnetic pattern152may have the same symmetry as an arrangement of atoms in the second magnetic pattern142. The second non-magnetic pattern152may include at least one of W, Mo, Nb, Ta or V.

One surface of the third magnetic pattern144may be in contact with the first non-magnetic pattern150, and the other surface of the third magnetic pattern144may be in contact with the second non-magnetic pattern152. The one surface and the other surface of the third magnetic pattern144may be opposite to each other. The third magnetic pattern144may include, for example, boron (B). Since the third magnetic pattern144is interposed between the first non-magnetic pattern150and the second non-magnetic pattern152, boron (B) in the third magnetic pattern144may be prevented (or suppressed) from being diffused into magnetic patterns (e.g., the first and second magnetic patterns140and142) adjacent thereto during a thermal treatment process. In some embodiments, at least a portion of the third magnetic pattern144may be amorphous. The third magnetic pattern144may include, for example, iron-boron (FeB).

In some embodiments, a crystal structure of lower patterns (e.g., the first non-magnetic pattern150and the first magnetic pattern140) under the third magnetic pattern144may be different from a crystal structure of upper patterns (i.e., the second non-magnetic pattern152and the second magnetic pattern142) over the third magnetic pattern144. The third magnetic pattern144may be provided between the first non-magnetic pattern150and the second non-magnetic pattern152having different crystal structures from each other.

The first non-magnetic pattern150may have a hexagonal close-packed (HCP) crystal structure or a face centered cubic (FCC) crystal structure, and when viewed in a plan view, an arrangement of atoms in the first non-magnetic pattern150may be provided to have the same symmetry as an arrangement of atoms in the first magnetic pattern140. In this case, at an interface between the first non-magnetic pattern150and the first magnetic pattern140, a magnetic moment of atoms in the first non-magnetic pattern150may be higher than when the first non-magnetic pattern150has a body centered cubic (BCC) crystal structure. Thus, a ferromagnetic coupling between the first magnetic pattern140and the second magnetic pattern142may be enhanced. Therefore, stability of magnetization of the reference magnetic structure RMS may be increased.

The second non-magnetic pattern152may have the same crystal structure as the second magnetic pattern142. When viewed in a plan view, an arrangement of atoms in the second non-magnetic pattern152may be provided to have the same symmetry as an arrangement of atoms in the second magnetic pattern142. In this case, the magnetic anisotropy of the second magnetic pattern142induced by a contact between the second magnetic pattern142and the tunnel barrier pattern TBR may be improved. Thus, tunneling magnetoresistance ratio (TMR) of the magnetic tunnel junction pattern MTJ may be improved.

In the case where at least a portion of the third magnetic pattern144is amorphous, it is possible to suppress that a crystal structure of the lower patterns (e.g., the first non-magnetic pattern150and the first magnetic pattern140) under the third magnetic pattern144affects a crystal growth of the upper patterns (i.e., the second non-magnetic pattern152and the second magnetic pattern142) over the third magnetic pattern144. Accordingly, the magnetic anisotropy of the second magnetic pattern142may be improved, and as a result, the tunneling magnetoresistance ratio (TMR) of the magnetic tunnel junction pattern MTJ may be improved. In the case where a thickness of the third magnetic pattern144is increased, it is possible to further reduce or minimize that the crystal structure of the lower patterns affects the crystal growth of the upper patterns. However, a ferromagnetic coupling between the first magnetic pattern140and the second magnetic pattern142may be weakened. According to embodiments of the inventive concepts, even though the thickness of the third magnetic pattern144is increased, the first non-magnetic pattern150may suppress weakening of the ferromagnetic coupling between the first magnetic pattern140and the second magnetic pattern142. Accordingly, it is possible to provide a magnetic memory device capable of increasing the stability of magnetization of the reference magnetic structure RMS, and improving the tunneling magnetoresistance ratio of the magnetic tunnel junction pattern MTJ.

Referring back toFIG. 3, the reference magnetic structure RMS may further include a seed pattern106between the bottom electrode BE and the first pinned pattern110. The seed pattern106may include a material contributing to a crystal growth of the first pinned pattern110. In some embodiments, the seed pattern106may include a conductive material having the same crystal structure as the first pinned pattern110. For example, the seed pattern106may include ruthenium (Ru).

The tunnel barrier pattern TBR may include at least one of magnesium oxide, titanium oxide, aluminum oxide, magnesium-zinc oxide, magnesium-boron oxide, titanium nitride or vanadium nitride. As an example, the tunnel barrier pattern TBR may include a magnesium oxide layer having a sodium chloride (NaCl) crystal structure.

The free magnetic structure FMS may include a free magnetic pattern170and a capping oxide pattern180. The free magnetic pattern170may be provided between the tunnel barrier pattern TBR and the capping oxide pattern180, and the capping oxide pattern180may be provided between the free magnetic pattern170and the top electrode TE.

The free magnetic pattern170may be in contact with the tunnel barrier pattern TBR. The free magnetic pattern170may exhibit a perpendicular magnetization property, which results from magnetic anisotropy induced by a contact between the free magnetic pattern170and the tunnel barrier pattern TBR. A magnetization direction170mof the free magnetic pattern170may be changed to be parallel or anti-parallel to the magnetization direction130mof the second pinned pattern130. A resistance value of the magnetic tunnel junction pattern MTJ may be dependent on the relative magnetization directions of the second pinned pattern130and the free magnetic pattern170. For example, the magnetic tunnel junction pattern MTJ may have a first resistance value when the magnetization direction130mof the second pinned pattern130is parallel to the magnetization direction170mof the free magnetic pattern170. The magnetic tunnel junction pattern MTJ may have a second resistance value higher than the first resistance value when the magnetization direction130mof the second pinned pattern130is anti-parallel to the magnetization direction170mof the free magnetic pattern170.

The free magnetic pattern170may include a magnetic material that induces the magnetic anisotropy at an interface between the free magnetic pattern170and the tunnel barrier pattern TBR. For example, the free magnetic pattern170may include cobalt-iron-boron (CoFeB).

The capping oxide pattern180may be in contact with the free magnetic pattern170. The magnetic anisotropy may be induced at an interface between the capping oxide pattern180and the free magnetic pattern170. As an example, oxygen atoms in the capping oxide pattern180may react with iron atoms in the free magnetic pattern170and the magnetic anisotropy may be induced by a bond between the oxygen atoms and iron atoms. Accordingly, the magnetic anisotropy of the free magnetic pattern170may be improved. The capping oxide pattern180may include, for example, magnesium oxide (MgO), tantalum oxide (TaO) and/or aluminum oxide (AlO).

A upper interlayer insulating layer190may be provided on the lower interlayer insulating layer102to extend on or cover the bottom electrode BE, the magnetic tunnel junction pattern MTJ and the top electrode TE. An upper contact plug192may be connected to the top electrode TE through the upper interlayer insulating layer190.

The upper interlayer insulating layer190may include oxide, nitride and/or oxynitride, and the upper contact plug192may include at least one of metals (e.g., titanium, tantalum, copper, aluminum or tungsten) or conductive metal nitrides (e.g., titanium nitride or tantalum nitride). An interconnection line194may be provided on the upper interlayer insulating layer190. The interconnection line194may be connected to the upper contact plug192. The interconnection line194may include at least one of metals (e.g., titanium, tantalum, copper, aluminum or tungsten) or conductive metal nitrides (e.g., titanium nitride or tantalum nitride). In some embodiments, the interconnection line194may serve as a bit line.

FIGS. 6 and 7are cross-sectional views illustrating a method for fabricating a magnetic memory device according to some embodiments of the inventive concepts.

Referring toFIG. 6, a lower interlayer insulating layer102may be formed on a substrate100. The substrate100may include a semiconductor substrate. For example, the substrate100may include a silicon substrate, a germanium substrate, a silicon-germanium substrate and so on. In some embodiments, selection elements may be formed on the substrate100, and the lower interlayer insulating layer102may be formed to extend on or cover the selection elements. The selection elements may be field effect transistors. Alternatively, the selection elements may be diodes. The lower interlayer insulating layer102may be formed to have a single- or multi-layered structure including oxide, nitride and/or oxynitride. The lower contact plug104may be formed in the lower interlayer insulating layer102. The lower contact plug104may be formed to penetrate the lower interlayer insulating layer102, and may be electrically connected to a terminal of a corresponding one of the selection elements. The lower contact plug104may include at least one of doped semiconductor materials (e.g., doped silicon), metals (e.g., tungsten, titanium and/or tantalum), conductive metal nitrides (e.g., titanium nitride, tantalum nitride and/or tungsten nitride) or metal-semiconductor compounds (e.g., metal silicide).

A bottom electrode layer BEL may be formed on the lower interlayer insulating layer102. The bottom electrode layer BEL may include conductive metal nitrides, such as titanium nitride and/or tantalum nitride. A seed layer106L may be formed on the bottom electrode layer BEL. The seed layer106L may include materials (e.g., ruthenium (Ru)) contributing to crystal growth of magnetic layers formed thereon. The bottom electrode layer BEL and the seed layer106L may be formed by a sputtering process, a chemical vapor deposition process, an atomic layer deposition process and so on.

A first pinned layer110L, an exchange coupling layer120L and a second pinned layer130L may be stacked on the seed layer106L. Specifically, the first pinned layer110L may be formed on the seed layer106L. The first pinned layer110L may be formed using the seed layer106L as a seed. The first pinned layer110L may have the same crystal structure as the seed layer106L. For example, the seed layer106L may include ruthenium (Ru) having a hexagonal close-packed crystal structure, and the first pinned layer110L may include a cobalt-platinum (CoPt) alloy having a hexagonal close-packed crystal structure or [Co/Pt]n (where n is the number of stacked pairs of layers). The exchange coupling layer120L may be formed on the first pinned layer110L. The exchange coupling layer120L may be formed using the first pinned layer110L as a seed. For example, the exchange coupling layer120L may include ruthenium (Ru) having a hexagonal close-packed crystal structure.

The second pinned layer130L may be formed on the exchange coupling layer120L. The second pinned layer130L may include a first magnetic layer140L, a first non-magnetic layer150L, a third magnetic layer144, a second non-magnetic layer152L and a second magnetic layer142L which are sequentially stacked on the exchange coupling layer120L. Specifically, the first magnetic layer140L may be formed on the exchange coupling layer120L. The first magnetic layer140L may be formed using the exchange coupling layer120L as a seed. The first magnetic layer140L may be formed to have a hexagonal close-packed (HCP) crystal structure or a face centered cubic (FCC) crystal structure, and a (0001) plane of the HCP crystal structure or a (111) plane of the FCC crystal structure may be parallel to a top surface of the substrate100. For example, the first magnetic layer140L may include at least one of cobalt (Co) or nickel (Ni). The first non-magnetic layer150L may be formed on the first magnetic layer140L. The first non-magnetic layer150L may be formed using the first magnetic layer140L as a seed. The first non-magnetic layer150L may be formed to have a hexagonal close-packed (HCP) crystal structure or a face centered cubic (FCC) crystal structure, and a (0001) plane of the HCP crystal structure or a (111) plane of the FCC crystal structure may be parallel to the top surface of the substrate100. For example, the first non-magnetic layer150L may include at least one of Ir, Rh, Pd, Ag, Ru, Y, Sc, Zr, Hf, Ti or Re. The third magnetic layer144L may be formed on the first non-magnetic layer150L. The third magnetic layer144L may be formed in an amorphous state during a deposition process. The third magnetic layer144L may include, for example, boron-doped iron (e.g., iron-boron (FeB)). The second non-magnetic layer152L may be formed on the third magnetic layer144L. The second non-magnetic layer152L may be formed to have a body centered cubic (BCC) crystal structure, and a (001) plane of the BCC crystal structure may be parallel to the top surface of the substrate100. For example, the second non-magnetic layer152L may include at least one of W, Mo, Nb, Ta or V. The second magnetic layer142L may be formed on the second non-magnetic layer152L. The second magnetic layer142L may be formed in an amorphous state during a deposition process. The second magnetic layer142L may include a different material from that of the third magnetic layer144L. For example, the second magnetic layer142L may include cobalt-iron-boron (CoFeB). The second magnetic layer142L may be formed using a sputtering process, a chemical vapor deposition process or an atomic layer deposition process.

A tunnel barrier layer TBRL may be formed on the second pinned layer130. The tunnel barrier layer TBRL may include at least one of magnesium (Mg) oxide, titanium (Ti) oxide, aluminum (Al) oxide, magnesium-zinc (Mg—Zn) oxide, or magnesium-boron (Mg—B) oxide. The tunnel barrier layer TBRL may be formed using, for example, a sputtering process.

A free magnetic layer170L and a capping oxide layer180L may be sequentially formed on the tunnel barrier layer TBRL. The free magnetic layer170L may be formed in an amorphous state during a deposition process. The free magnetic layer170L may include, for example, cobalt-iron-boron (CoFeB). The free magnetic layer170L may be formed using a sputtering process, a chemical vapor deposition process or an atomic layer deposition process. The capping oxide layer180L may include, for example, magnesium oxide (MgO), tantalum oxide (TaO) and/or aluminum oxide (AlO). The capping oxide layer180L may be formed using a sputtering process.

After the capping oxide layer180L is formed, a thermal treatment process (H) may be performed. The thermal treatment process H may also be performed after forming the free magnetic layer170L and before forming the capping oxide layer180L. The second magnetic layer142L and the free magnetic layer170L may be crystallized by the thermal treatment process H. The crystallized second magnetic layer142L may have the same crystal structure as the second non-magnetic layer152L. The crystallized second magnetic layer142L may be crystallized using the tunnel barrier layer TBRL as a seed during the thermal heat treatment process H. For example, the tunnel barrier layer TBRL may have a sodium chloride-type crystal structure, and the crystallized second magnetic layer142L may have a body centered cubic (BCC) crystal structure. The crystallized free magnetic layer170L may have the same crystal structure as the crystallized second magnetic layer142L. The crystallized free magnetic layer170L may be crystallized using the tunnel barrier layer TBRL as a seed during the thermal treatment process H. For example, the tunnel barrier layer TBRL may have a sodium chloride-type crystal structure, and the crystallized free magnetic layer170L may have a body centered cubic (BCC) crystal structure.

At least a portion of the third magnetic layer144L may be in an amorphous state even after the thermal treatment process H. As the third magnetic layer144L may be interposed between the first and second non-magnetic layers150L and152L, boron (B) in the third magnetic layer144L may be prevented (or suppressed) from being diffused out of the third magnetic layer144L during the thermal treatment process H. Accordingly, at least a portion of the third magnetic layer144L may remain in an amorphous state even after the thermal treatment process H.

Referring toFIG. 7, a conductive mask pattern200may be formed on the capping oxide layer180L. The conductive mask pattern200may include at least one of tungsten, titanium, tantalum, aluminum or metal nitrides (e.g., titanium nitride or tantalum nitride). The conductive mask pattern200may be used to define a position and a shape for forming a magnetic tunnel junction pattern to be described later. The capping oxide layer180L, the free magnetic layer170L, the tunnel barrier layer TBRL, the second pinned layer130L, the exchange coupling layer120L, the first pinned layer110L, the seed layer106L and the bottom electrode layer BEL may be sequentially etched using the conductive mask pattern200as an etch mask. The etching process may be performed using, for example, an ion beam etching process. As a result of the etching process, a bottom electrode BE, a seed pattern106, a first pinned pattern110, an exchange coupling pattern120, a second pinned pattern130, a tunnel barrier pattern TBR, a free magnetic pattern170and a capping oxide pattern180may be sequentially formed on the lower interlayer insulating layer102. The second pinned pattern130may include a first magnetic pattern140adjacent the exchange coupling pattern120, a second magnetic pattern142adjacent the tunnel barrier pattern TBR, a third magnetic pattern144between the first magnetic pattern140and a second magnetic pattern142, a first non-magnetic pattern150between the first magnetic pattern140and the third magnetic pattern144, and a second non-magnetic pattern152between the second magnetic pattern142and the third magnetic pattern144. The seed pattern106, the first pinned pattern110, the exchange coupling pattern120and the second pinned pattern130may constitute or define a reference magnetic structure RMS. The free magnetic pattern170and the capping oxide pattern180may constitute or define a free magnetic structure FMS. The reference magnetic structure RMS, the free magnetic structure FMS, and the tunnel barrier pattern TBR therebetween may constitute or define a magnetic tunnel junction pattern MTJ. The bottom electrode BE may be electrically connected to the lower contact plug104formed in the lower interlayer insulating layer102. The conductive mask pattern200may serve as a top electrode TE. The magnetic tunnel junction pattern MTJ may be formed between the bottom electrode BE and the top electrode TE.

Referring back toFIG. 3, the upper interlayer insulating layer190may be formed on the lower interlayer insulating layer102so as to extend on or cover the bottom electrode BE, the magnetic tunnel junction pattern MTJ and the top electrode TE. The upper contact plug192may be formed to penetrate the upper interlayer insulating layer190, and may be connected to the top electrode TE. An interconnection line194may be formed on the upper interlayer insulating layer190. The interconnection line194may be connected to the upper contact plug192. In some embodiments, the interconnection line194may serve as a bit line.

FIG. 8is a cross-sectional view illustrating a magnetic memory device according to some embodiments of the inventive concepts. In the following description, an element previously described with reference toFIGS. 3, 4, 5A and 5Bmay be identified by a similar or identical reference number without repeating an overlapping description thereof, for the sake of brevity.

Referring toFIG. 8, a lower interlayer insulating layer102may be provided on a substrate100. Selection elements may be provided on the substrate100, and the lower interlayer insulating layer102may be provided to extend on or cover the selection elements. A lower contact plug104may be provided in the lower interlayer insulating layer102. The lower contact plug104may be provided to penetrate the lower interlayer insulating layer102, and may be electrically connected to a terminal of a corresponding one of selection elements.

A bottom electrode BE may be provided on the lower interlayer insulating layer102. The bottom electrode BE may be electrically connected to the lower contact plug104. A reference magnetic structure RMS and a free magnetic structure FMS may be stacked on the lower interlayer insulating layer102. A tunnel barrier pattern TBR may be provided between the reference magnetic structure RMS and the free magnetic structure FMS. In some embodiments, the free magnetic structure FMS may be provided between the bottom electrode BE and the tunnel barrier pattern TBR.

The reference magnetic structure RMS may include at least one fixed layer having a fixed magnetization direction, and the free magnetic structure FMS may include at least one free layer having a switchable magnetization direction. The reference magnetic structure RMS, the free magnetic structure FMS and the tunnel barrier pattern TBR may constitute or define a magnetic tunnel junction pattern MTJ. The magnetization directions of the fixed layer and the free layer may be substantially perpendicular to an interface between the tunnel barrier pattern TBR and the free magnetic structure FMS. That is, the magnetic tunnel junction pattern MTJ may be a perpendicular magnetization-type magnetic tunnel junction pattern.

A top electrode TE may be provided on the magnetic tunnel junction pattern MTJ. The magnetic tunnel junction pattern MTJ may be disposed between the bottom electrode BE and the top electrode TE. In some embodiments, the reference magnetic structure RMS may be provided between the tunnel barrier pattern TBR and the top electrode TE. The bottom electrode BE, the magnetic tunnel junction pattern MTJ and the top electrode TE may be provided to have a vertical-aligned sidewalls.

The free magnetic structure FMS may include a free magnetic pattern170between the bottom electrode BE and the tunnel barrier pattern TBR. In some embodiments, the bottom electrode BE may include a material contributing to crystal growth of the free magnetic pattern170. The free magnetic pattern170may be in contact with the tunnel barrier pattern TBR. The free magnetic pattern170may exhibit a perpendicular magnetization property, which results from magnetic anisotropy induced by a contact between the free magnetic pattern170and the tunnel barrier pattern TBR. The free magnetic pattern170may include a magnetic material that induces magnetic anisotropy at an interface between the free magnetic pattern170and the tunnel barrier pattern TBR. For example, the free magnetic pattern170may include cobalt-iron-boron (CoFeB).

The reference magnetic structure RMS may include a synthetic antiferromagnetic (SAF) structure. For example, the reference magnetic structure RMS may include a first pinned pattern110between the tunnel barrier pattern TBR and the top electrode TE, a second pinned pattern130between the first pinned pattern110and the tunnel barrier pattern TBR, and an exchange coupling pattern120between the first pinned pattern110and the second pinned pattern130. The exchange coupling pattern120may couple the first pinned pattern110to the second pinned pattern130in such a way that a magnetization direction110mof the first pinned pattern110is anti-parallel to a magnetization direction130mof the second pinned pattern130. The exchange coupling pattern120may include, for example, ruthenium (Ru). The first pinned pattern110may include substantially the same material as the first pinned pattern110according to some embodiments described with reference toFIG. 3.

The second pinned pattern130may include a first magnetic pattern140adjacent the exchange coupling pattern120, a second magnetic pattern142adjacent the tunnel barrier pattern TBR, a third magnetic pattern144between the first magnetic pattern140and the second magnetic pattern142, a first non-magnetic pattern150between the first magnetic pattern140and the third magnetic pattern144, and a second non-magnetic pattern152between the second magnetic pattern142and the third magnetic pattern144. The first to third magnetic patterns140,142and144and the first and second non-magnetic patterns150and152may be substantially the same as the first to third magnetic patterns140,142and144and the first and second non-magnetic patterns150and152according to some embodiments described with reference toFIGS. 3, 4, 5A and 5B.

A magnetization direction170mof the free magnetic pattern170may be changed to be parallel or anti-parallel to the magnetization direction130mof the second pinned pattern130. A resistance value of the magnetic tunnel junction pattern MTJ may be dependent on the relative magnetization directions of the second pinned pattern130and the free magnetic pattern170. For example, the magnetic tunnel junction pattern MTJ may have a first resistance value when the magnetization direction130mof the second pinned pattern130is parallel to the magnetization direction170mof the free magnetic pattern170. The magnetic tunnel junction pattern MTJ may have a second resistance value higher than the first resistance value when the magnetization direction130mof the second pinned pattern130is anti-parallel to the magnetization direction170mof the free magnetic pattern170.

The upper interlayer insulating layer190may be provided on the lower interlayer insulating layer102to extend on or cover the bottom electrode BE, the magnetic tunnel junction pattern MTJ and the top electrode TE. The upper contact plug192may be provided to penetrate the upper interlayer insulating layer190, and may be connected to the top electrode TE. An interconnection line194may be provided on the upper interlayer insulating layer190, and may be connected to the upper contact plug192. In some embodiments, the interconnection line194may serve as a bit line.

FIGS. 9 to 11are cross-sectional views illustrating a method for fabricating a magnetic memory device according to some embodiments of the inventive concepts. In the following description, an element previously described with reference toFIGS. 6 and 7may be identified by a similar or identical reference number without repeating an overlapping description thereof, for the sake of brevity.

Referring toFIG. 9, a lower interlayer insulating layer102may be formed on a substrate100. Selection elements may be formed on the substrate100, and the lower interlayer insulating layer102may be formed to extend on or cover the selection elements. A lower contact plug104may be formed in the lower interlayer insulating layer102. The lower contact plug104may be formed to penetrate the lower interlayer insulating layer102, and may be electrically connected to a terminal of corresponding one of the selection elements.

A bottom electrode layer BEL may be formed on the lower interlayer insulating layer102. The bottom electrode layer BEL may include conductive metal nitrides, such as titanium nitride and/or tantalum nitride. According to some embodiments, the bottom electrode layer BEL may further include a material contributing to crystal growth of magnetic layers formed thereon. A free magnetic layer170L may be formed on the bottom electrode layer BEL. The free magnetic layer170L may be in an amorphous state during a deposition process. The free magnetic layer170L may include, for example, cobalt-iron-boron (CoFeB). A tunnel barrier layer TBRL may be formed the free magnetic layer170L. The tunnel barrier layer TBRL may be the same as the tunnel barrier layer TBRL described with reference toFIG. 6.

A second magnetic layer142L may be formed on the tunnel barrier layer TBRL. The second magnetic layer142L may be in an amorphous state during a deposition process. The second magnetic layer142L may include the same material as the second magnetic layer142L. The second magnetic layer142L may include, for example, cobalt-iron-boron (CoFeB).

In some embodiments, a thermal treatment process H may be performed after forming the second magnetic layer142L. The second magnetic layer142L and the free magnetic layer170L may be crystallized by the thermal treatment process H. The crystallized free magnetic layer170L may have the same crystal structure as the crystallized second magnetic layer142L. The crystallized free magnetic layer170L and the crystallized second magnetic layer142L may be crystallized using the tunnel barrier layer TBRL as a seed during the thermal treatment process H. For example, the tunnel barrier layer TBRL may have a sodium chloride-type crystal structure, and the crystallized free magnetic layer170L and the crystallized second magnetic layer142L may have a body centered cubic (BCC) crystal structure. In other embodiments, the thermal treatment process H may be performed after forming magnetic and non-magnetic layers to be described later.

Referring toFIG. 10, a second non-magnetic layer152L may be formed on the second magnetic layer142L. The second non-magnetic layer152L may have the same crystal structure as the second magnetic layer142L. The second non-magnetic layer152L may be formed to have a body centered cubic (BCC) crystal structure, a (001) plane of the body centered cubic (BCC) crystal structure may be parallel to a top surface of the substrate100. The second non-magnetic layer152L may include, for example, at least one of W, Mo, Nb, Ta or V. The third magnetic layer144L may be formed on the second non-magnetic layer152L. The third magnetic layer144L may be formed in an amorphous state during a deposition process. For example, the third magnetic layer144L may include, for example, boron-doped iron (e.g., iron-boron (FeB)). A first non-magnetic layer150L may be formed on the third magnetic layer144L. The first non-magnetic layer150L may be formed to have a hexagonal close-packed (HCP) crystal structure or a face centered cubic (FCC) crystal structure, and a (0001) plane of the HCP crystal structure or a (111) plane of the FCC crystal structure may be parallel to the top surface of the substrate100. For example, the first non-magnetic layer150L may include at least one of Ir, Rh, Pd, Ag, Ru, Y, Sc, Zr, Hf, Ti or Re. A first magnetic layer140L may be formed on the first non-magnetic layer150L. The first magnetic layer140L may be formed using the first non-magnetic layer150L as a seed. The first magnetic layer140L may be formed to have a hexagonal close-packed (HCP) crystal structure or a face centered cubic (FCC) crystal structure, and a (0001) plane of the HCP crystal structure or a (111) plane of the FCC crystal structure may be parallel to the top surface of the substrate100. For example, the first magnetic layer140L may include at least one of cobalt (Co) or nickel (Ni). The first to third magnetic layers140L,142L and144L, and the first and second non-magnetic layers150L and152L may constitute or define a second pinned layer130L.

An exchange coupling layer120L may be formed on the second pinned layer130L. The exchange coupling layer120L may be formed using the first magnetic layer140L as a seed. For example, the exchange coupling layer120L may include ruthenium (Ru) having a hexagonal close-packed crystal structure. A first pinned layer110L may be formed on the exchange coupling layer120L. The first pinned layer110L may be formed using the exchange coupling layer120L as a seed. The first pinned layer110L may include a cobalt-platinum (CoPt) alloy having a hexagonal close-packed crystal structure or [Co/P]n (where n is the number of stacked pairs of layers).

In some embodiments, the thermal treatment process H, described with reference toFIG. 9, may be performed after forming the first pinned layer110L. In this case, as described with reference toFIG. 9, the second magnetic layer142L and the free magnetic layer170L may be crystallized by the thermal treatment process H. At least a portion of the third magnetic layer144L may be in an amorphous state even after the thermal treatment process. Since the third magnetic layer144L may be interposed between the first and second non-magnetic layers150L and152L, boron (B) in the third magnetic layer144L may be prevented (or suppressed) from being diffused out of the third magnetic layer144L during the thermal treatment process H. Accordingly, at least a portion of the third magnetic layer144L may remain in an amorphous state even after the thermal treatment process H.

Referring toFIG. 11, a conductive mask pattern200may be formed on the first pinned layer110L. The conductive mask pattern200may be used to define a position and a shape for forming a magnetic tunnel junction pattern to be described later. The first pinned layer110L, the exchange coupling layer120L, the second pinned layer130L, the tunnel barrier layer TBRL, the free magnetic layer170L, and the bottom electrode layer BEL may be sequentially etched using the conductive mask pattern200as an etch mask. As a result of the etching process, a bottom electrode BE, a free magnetic pattern170, a tunnel barrier pattern TBR, a second pinned pattern130, an exchange coupling pattern120, and a first pinned pattern110may be sequentially formed on the lower interlayer insulating layer102. The second pinned pattern130may include a first magnetic pattern140adjacent the exchange coupling pattern120, a second magnetic pattern142adjacent the tunnel barrier pattern TBR, a third magnetic pattern144between the first magnetic pattern140and a second magnetic pattern142, a first non-magnetic pattern150between the first magnetic pattern140and the third magnetic pattern144, and a second non-magnetic pattern152between the second magnetic pattern142and the third magnetic pattern144. The first pinned pattern110, the exchange coupling pattern120and the second pinned pattern130may constitute or define a reference magnetic structure RMS. The free magnetic pattern170may constitute or define a free magnetic structure FMS. The reference magnetic structure RMS, the free magnetic structure FMS, and the tunnel barrier pattern TBR therebetween may constitute or define a magnetic tunnel junction pattern MTJ. The bottom electrode BE may be electrically connected to the lower contact plug104formed in the lower interlayer insulating layer102. The conductive mask pattern200may serve as a top electrode TE. The magnetic tunnel junction pattern MTJ may be formed between the bottom electrode BE and the top electrode TE.

A subsequent process may be performed in substantially the same manner as that of the method described with reference toFIG. 3.

According to embodiments of the inventive concepts, a reference magnetic structure of a magnetic tunnel junction pattern may include a first magnetic pattern, a second magnetic pattern, a third magnetic pattern between the first magnetic pattern and the second magnetic pattern, a first non-magnetic pattern between the first magnetic pattern and the third magnetic pattern, and a second non-magnetic pattern between the second magnetic pattern and the third magnetic pattern. At least a portion of the third magnetic pattern may be in an amorphous state, and the first non-magnetic pattern and the second non-magnetic pattern may have a different crystal structure from each other.

The first non-magnetic pattern may have a hexagonal close-packed (HCP) crystal structure or a face centered cubic (FCC) crystal structure. When viewed in a plan view, an arrangement of atoms in the first non-magnetic pattern may be provided to have the same symmetry as an arrangement of atoms in the first magnetic pattern. In this case, a magnetic moment of atoms in the first non-magnetic pattern may be relatively high at an interface between the first non-magnetic pattern and the first magnetic pattern.

The second non-magnetic pattern may be provided to have the same crystal structure (for example, body centered cubic (BCC) crystal structure) as the second magnetic pattern. When viewed in a plan view, an arrangement of atoms in the second non-magnetic pattern may be provided to have the same symmetry as an arrangement of atoms in the second magnetic pattern. In this case, the magnetic anisotropy of the second magnetic pattern induced by a contact between the second magnetic pattern and the tunnel barrier pattern may be improved. When at least a portion of the third magnetic pattern is amorphous, it is possible to suppress that a crystal structure of lower patterns (e.g., the first non-magnetic pattern and the first magnetic pattern) under the third magnetic pattern affects crystal growth of upper patterns (e.g., the second non-magnetic pattern and the second magnetic pattern) over the third magnetic pattern.

Accordingly, it is possible to provide a magnetic memory device capable of increasing the stability of magnetization of the reference magnetic structure RMS, and improving the tunneling magnetoresistance ratio of the magnetic tunnel junction MTJ.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments. It will be understood that when an element is referred to as being “on” or “connected to” or “adjacent” another element (e.g., a layer or substrate), it can be directly on or connected to or adjacent the other element, or intervening elements may also be present. In contrast, when an element is referred to as being “directly on” or “directly connected to” or “immediately adjacent” another element, there are no intervening elements present.

It will be understood that spatially relative terms, such as “beneath,” “below,” “lower,” “above,” “upper” and the like, are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

The use of the terms “a” and “an” and “the” and similar references herein are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms “comprising,” “having,” “including,” and “containing” are to be construed as open-ended terms (i.e., meaning “including, but not limited to,”) unless otherwise noted. The term “and/or” includes any and all combinations of one or more of the associated listed items.