Magnetic property measurement system and method and method for manufacturing magnetic storage device using the same

Abstract

The present invention discloses a magnetic property measurement system, a method for measuring magnetic properties, and a method for manufacturing a magnetic storage device using the same, wherein the magnetic property measurement system includes a platform configured to hold a sample and a magnetic structure arranged above the platform. The platform includes a main body, a magnetic part adjacent to the main body, and a plurality of holes defined in the main body. The magnetic part and the magnetic structure of the platform are configured to apply a magnetic field perpendicular to a surface of the sample to the sample. The platform is configured to move horizontally in a first direction and a second direction parallel to the one surface of the sample and perpendicular to each other.

Description

Technical Field

[0001] Embodiments of the present inventive concept relate to a magnetic property measurement system, a method for measuring magnetic properties, and a method for manufacturing a magnetic memory device using the same. More specifically, embodiments of the present inventive concept relate to a system and method for measuring the magnetic properties of a magnetic tunnel junction by using a magneto-optical Kerr effect (MOKE), and a method for manufacturing a magnetic memory device using the same. Background Art

[0002] Since electronic devices with high speed and / or low power consumption are required, semiconductor memory devices with high speed and / or low voltage used therein are also required. Magnetic memory devices have been developed as semiconductor memory devices that can meet these requirements. The magnetic memory device may include a magnetic tunnel junction (MTJ) pattern. The magnetic tunnel junction pattern may include two magnetic layers and an insulating layer disposed between the two magnetic layers. The resistance value of the magnetic tunnel junction pattern may change according to the magnetization directions of the two magnetic layers. For example, when the magnetization directions of the two magnetic layers are antiparallel to each other or not parallel to each other, the magnetic tunnel junction pattern may have a relatively high resistance value. When the magnetization directions of the two magnetic layers are parallel to each other, the magnetic tunnel junction pattern may have a relatively low resistance value. The magnetic memory device may use the difference between the resistance values ​​of the magnetic tunnel junction pattern to read / write data.

[0003] When the magnetization directions of the two magnetic layers are substantially perpendicular to the interface between the insulating layer and the magnetic layer, the magnetic tunnel junction pattern can be defined as a perpendicular magnetic tunnel junction pattern. A measurement system using the polar magneto-optical Kerr effect (polar MOKE) can be used to measure the perpendicular magnetic properties of the perpendicular magnetic tunnel junction pattern. Summary of the invention

[0004] Embodiments of the inventive concept may provide a magnetic property measurement system and method capable of measuring effective magnetic properties of a magnetic tunnel junction pattern on various regions of a sample.

[0005] Embodiments of the inventive concept may also provide a magnetic property measurement system and method capable of stably measuring magnetic properties of a magnetic tunnel junction pattern.

[0006] Embodiments of the inventive concept may also provide a method for manufacturing a magnetic memory device, which can improve mass production and quality stability.

[0007] In one aspect, a magnetic property measurement system may include: a platform configured to hold a sample; and a magnetic structure disposed above the platform. The platform may include a main body portion, a magnetic portion adjacent to the main body portion, and a plurality of holes defined in the main body portion. The magnetic portion and the magnetic structure of the platform may be configured to apply a magnetic field perpendicular to one surface of the sample to the sample. The platform may be configured to move horizontally in a first direction and a second direction parallel to the one surface of the sample and perpendicular to each other.

[0008] In one aspect, a method for measuring magnetic properties may include: loading a sample on a platform; fixing the sample on the platform by using a vacuum; moving a measurement target area of ​​the sample to a light irradiation area by horizontally moving the platform in a first direction and a second direction parallel to a top surface of the sample and perpendicular to each other; irradiating incident light to the measurement target area of ​​the sample; and detecting the polarization of light reflected from the measurement target area of ​​the sample.

[0009] In one aspect, a method for manufacturing a magnetic memory device may include: forming a magnetic tunnel junction layer on a substrate; patterning the magnetic tunnel junction layer to form a magnetic tunnel junction pattern; measuring magnetic properties of the magnetic tunnel junction pattern; and determining whether the measured magnetic properties are within an allowable range. Measuring the magnetic properties of the magnetic tunnel junction pattern may include: loading the substrate on a platform in a magnetic property measurement system; fixing the substrate on the platform by using a vacuum; moving a measurement target area of ​​the substrate to a light irradiation area by horizontally moving the platform in a first direction and a second direction parallel to a top surface of the substrate and perpendicular to each other; irradiating incident light to the measurement target area of ​​the substrate; and detecting polarization of light reflected from the measurement target area of ​​the substrate. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The inventive concept will become more apparent in view of the accompanying drawings and the accompanying detailed description.

[0011] Figure 1 is a conceptual diagram illustrating a magnetic property measurement system according to some embodiments of the present inventive concept.

[0012] Figure 2 It is shown Figure 1 A floor plan of the stage.

[0013] Figure 3 It is along Figure 2 A cross-sectional view taken along line II'.

[0014] Figure 4 It is shown Figure 1 Exploded perspective view of the platform.

[0015] FIG. 5A to FIG. 5D It is shown Figure 1 Plan views of various modified examples of the platform.

[0016] Figure 6 is a conceptual diagram illustrating a magnetic property measurement system according to some embodiments of the present inventive concept.

[0017] Figure 7 It is shown Figure 6 Floor plan of the platform.

[0018] Figure 8 It is along Figure 7 A cross-sectional view taken along line II'.

[0019] Fig. 9 It is shown Figure 6 Exploded perspective view of the platform.

[0020] Fig.10 is a flow chart illustrating a method for measuring magnetic properties according to some embodiments of the present inventive concept.

[0021] Fig.11 is a plan view illustrating a sample used in a method of measuring a magnetic property according to some embodiments of the inventive concept.

[0022] Fig.12 yes Fig.11 Cross-sectional view of a region of the sample.

[0023] Fig.13 yes Fig.12 An enlarged view of portion 'A'.

[0024] Fig.14 and Fig.15 2 are a plan view and a cross-sectional view, respectively, to illustrate a method for measuring magnetic properties according to some embodiments of the present inventive concept.

[0025] Fig.16 is a flowchart illustrating a method of manufacturing a magnetic memory device using a magnetic property measurement system according to some embodiments of the inventive concept.

[0026] Figures 17 to 19 2 is a cross-sectional view illustrating a method of manufacturing a magnetic memory device using a magnetic property measurement system according to some embodiments of the inventive concept.

[0027] Fig. 20 is a circuit diagram illustrating a unit memory cell of a magnetic memory device manufactured according to some embodiments of the inventive concept. DETAILED DESCRIPTION

[0028] Hereinafter, embodiments of the inventive concept will be described in detail with reference to the accompanying drawings.As used herein, the expression "and / or" includes any and all combinations of one or more of the associated listed items.

[0029] Figure 1 is a conceptual diagram illustrating a magnetic property measurement system according to some embodiments of the present inventive concept. Figure 2 It is shown Figure 1 The floor plan of the platform, Figure 3 It is along Figure 2 A cross-sectional view taken along line II'. Figure 4 It is shown Figure 1 Exploded perspective view of the platform.

[0030] Reference Figure 1 , the magnetic property measurement system 1000 may include: a chamber 500 configured to receive a sample S therein; a platform 10 provided in the chamber 500 and configured to load or hold the sample S; a support member 20 for supporting the platform 10; a magnetic structure MS disposed above the platform 10 in the chamber 500; a light source 50 configured to emit incident light Li; and a detector 70 configured to receive reflected light Lr reflected from the sample S. The magnetic property measurement system 1000 may also include a polarizer 55 for polarizing the incident light Li emitted from the light source 50, a first optical member 60 and a second optical member 65 for controlling an optical path of the incident light Li, and an analyzer 75 for polarizing the reflected light Lr. The incident light Li may be polarized by the polarizer 55, and the polarized incident light Li may be reflected by the first optical member 60 and the second optical member 65, and then may be irradiated to the top surface or upper surface SU of the sample S. The reflected light Lr may be polarized by the analyzer 75, and the polarized reflected light Lr may be received at or by the detector 70. The polarization axis of the polarizer 55 may be perpendicular to the polarization axis of the analyzer 75 .

[0031] The platform 10 may include a main body portion BP and a magnetic portion MP adjacent to the main body portion BP. The magnetic portion MP may include, for example, a magnetic material. The magnetic structure MS may include a pole piece 40 and a coil 42 surrounding the outer peripheral surface of the pole piece 40. The pole piece 40 may include, for example, a magnetic material. The magnetic portion MP and the magnetic structure MS of the platform 10 may be configured to apply a magnetic field H substantially perpendicular to the top surface SU of the sample S to the sample S.

[0032] The platform 10 may further include a plurality of holes PH defined or disposed in the body part BP and / or the magnetic part MP. Each of the plurality of holes PH may be connected to a vacuum line VL disposed in the body part BP. The magnetic property measurement system 1000 may further include a vacuum pump 30 connected to the vacuum line VL.

[0033] Reference Figures 2 to 4According to some embodiments, the magnetic portion MP may be disposed on (e.g., directly on) the body portion BP. For example, the magnetic portion MP may be a coating coated on the top surface or upper surface BP_U of the body portion BP. The plurality of holes PH may extend into the magnetic portion MP and may penetrate the magnetic portion MP. In some embodiments, when viewed in a plan view, the plurality of holes PH may be disposed adjacent to the center of the sample S and may be disposed around the center of the sample S. For example, when viewed in a plan view, the plurality of holes PH may be arranged in an imaginary circle around the center of the sample S. However, according to certain embodiments of the present inventive concept, the number, size, shape and / or arrangement of the plurality of holes PH may be variously modified, as described below with reference to FIG. 5A to FIG. 5D In some embodiments, the sample S can be placed on the top surface or upper surface MP_U of the magnetic portion MP of the platform 10 .

[0034] The platform 10 may be configured to fix the sample S on the platform 10 by using vacuum. The platform 10 may fix the sample S on the platform 10 by extracting or sucking air through the plurality of holes PH. For example, each of the plurality of holes PH may be connected to a vacuum line VL, and the vacuum line VL may be connected to Figure 1 The vacuum pump 30 is provided. When the vacuum pump 30 is operated, the air in the space between the sample S and the platform 10 can be extracted or sucked through the plurality of holes PH and the vacuum line VL. Therefore, the sample S can be pulled to the surface of the platform 10 (e.g., the top surface MP_U of the magnetic part MP) and can be fixed on the surface of the platform 10 (e.g., the top surface MP_U of the magnetic part MP).

[0035] The platform 10 may be configured to move horizontally in a first direction D1 and a second direction D2 parallel to the top surface SU of the sample S. The first direction D1 and the second direction D2 may intersect each other. For example, the first direction D1 and the second direction D2 may be perpendicular to each other and may correspond to the x-direction and the y-direction, respectively. For example, the platform 10 may be an XY platform having a repeatability accuracy of 100 nm or less.

[0036] Refer again Figure 1 , the light source 50 may be a laser light source. The light source 50 may be used as a single light source of the magnetic property measurement system 1000. The incident light Li polarized by the polarizer 55 may be reflected by the first optical member 60 and the second optical member 65, and then may be irradiated to the sample S. The incident light Li may be irradiated perpendicularly to the top surface SU of the sample S. However, embodiments of the inventive concept are not limited thereto. In some embodiments, the incident light Li may be irradiated obliquely to the top surface SU of the sample S.

[0037] The detector 70 may detect polarization of the reflected light Lr reflected from the sample S. The reflected light Lr may pass through the second optical member 65 to be guided to the analyzer 75 and may be polarized by the analyzer 75. The polarized reflected light Lr may be received at or by the detector 70.

[0038] The magnetic property measurement system 1000 may further include a controller 80 connected to or operably connected to the light source 50 and the detector 70. The controller 80 may process data obtained from the detector 70. The controller 80 may process, store and / or display the data obtained from the detector 70 in various forms (e.g., numerical values, graphs and / or images). Even if not shown in the drawings, the controller 80 may be connected to or operably connected to the platform 10 and may control the operation of the platform 10.

[0039] The magnetic property measurement system 1000 can be configured to measure the perpendicular magnetic properties of the sample S by using the polar magneto-optical Kerr effect (polar MOKE). The magneto-optical Kerr effect (MOKE) refers to the phenomenon that the polarization of light changes when light is reflected from a magnetic object. Polar MOKE refers to the situation where the magnetization direction of an object is perpendicular to the surface of the object and parallel to the surface (i.e., the incident surface) on which the light is incident and reflected. The magnetic property measurement system 1000 can be a polar MOKE measurement system and can measure the degree of perpendicular magnetization of the surface of the sample S by analyzing the polarization of the light reflected from the top surface SU of the sample S (i.e., the reflected light Lr). For example, the detector 70 can detect the polarization of the reflected light Lr, and the controller 80 can generate a hysteresis curve about the surface of the sample S based on the data obtained from the detector 70.

[0040] FIG. 5A to FIG. 5D It is shown Figure 1 Plan views of various modified examples of the platform.

[0041] Reference Figure 5A According to a modified example, when viewed in a plan view, the plurality of holes PH may be arranged in the form of an imaginary cross passing through the center of the sample S. For example, when viewed in a plan view, one hole PH among the plurality of holes PH may be disposed at the center of the sample S. At least one pair of holes PH among the plurality of holes PH may be spaced apart from each other in the first direction D1, with the one hole PH (e.g., the center hole) interposed therebetween, and at least another pair of holes PH among the plurality of holes PH may be spaced apart from each other in the second direction D2, with the one hole PH (e.g., the center hole) interposed therebetween.

[0042] Reference Figure 5B According to a modified example, when viewed in a plan view, the plurality of holes PH may be disposed adjacent to an edge of the sample S and may be arranged along an outer peripheral surface or outer peripheral portion of the sample S. Figure 5CAccording to a modified example, when viewed in a plan view, the plurality of holes PH may be uniformly distributed in a region that overlaps all or the entirety of the top surface SU of the sample S. Figure 5D According to a modified example, when viewed in a plan view, the plurality of holes PH may be disposed adjacent to the center of the sample S and may be arranged around the center of the sample S. For example, when viewed in a plan view, the plurality of holes PH may be arranged in an imaginary ellipse around the center of the sample S. However, according to certain embodiments of the inventive concept, the number, size, shape, and / or arrangement of the plurality of holes PH are not limited to the illustrated embodiments but may be variously modified.

[0043] Figure 6 is a conceptual diagram illustrating a magnetic property measurement system according to some embodiments of the present inventive concept. Figure 7 It is shown Figure 6 The floor plan of the platform, Figure 8 It is along Figure 7 A cross-sectional view taken along line II'. Fig. 9 It is shown Figure 6 Hereinafter, for the sake of ease and convenience of explanation, the present embodiment and Figures 1 to 4 and FIG. 5A to FIG. 5D differences between the implementations of

[0044] Reference Figure 6 , the platform 10 may include a main body part BP and a magnetic part MP adjacent to the main body part BP. The magnetic part MP may include, for example, a magnetic material. The magnetic part MP and the magnetic structure MS of the platform 10 may be configured to apply a magnetic field H substantially perpendicular to the top surface SU of the sample S to the sample S. According to the present embodiment, the magnetic part MP may be disposed in the main body part BP. The main body part BP may include an upper main body part UBP and a lower main body part LBP, and the magnetic part MP may be disposed between the upper main body part UBP and the lower main body part LBP. The upper main body part UBP may be directly on the magnetic part MP and / or the magnetic part MP may be directly on the lower main body part LBP. The platform 10 may also include a plurality of holes PH defined in or disposed in the main body part BP and / or the magnetic part MP. Each of the plurality of holes PH may be connected to a vacuum line VL disposed in the main body part BP.

[0045] Reference Figures 7 to 9 , the plurality of holes PH may be provided in the lower body portion LBP, and each of the plurality of holes PH may be connected to a vacuum line VL provided in the lower body portion LBP. The plurality of holes PH may extend into the magnetic portion MP and the upper body portion UBP, and may penetrate the magnetic portion MP and the upper body portion UBP. The number, size, shape and / or arrangement of the plurality of holes PH may be as described above with reference to FIG. 5A to FIG. 5D The platform 10 may be configured such that the sample S is placed on the top surface or upper surface BP_U of the body portion BP (ie, the top surface or upper surface of the upper body portion UBP).

[0046] The platform 10 may be configured to fix the sample S on the platform 10 by using vacuum. The platform 10 may fix the sample S on the platform 10 by extracting or sucking air through the plurality of holes PH. For example, each of the plurality of holes PH may be connected to a vacuum line VL, and the vacuum line VL may be connected to Figure 6 The vacuum pump 30 is provided. When the vacuum pump 30 is operated, the air in the space between the sample S and the platform 10 can be extracted or sucked through the plurality of holes PH and the vacuum line VL. Therefore, the sample S can be pulled to the surface of the platform 10 (e.g., the top surface BP_U of the body part BP) and can be fixed on the surface of the platform 10 (e.g., the top surface BP_U of the body part BP).

[0047] The platform 10 may be configured to move horizontally in a first direction D1 and a second direction D2 parallel to the top surface SU of the sample S. The first direction D1 and the second direction D2 may intersect each other. For example, the first direction D1 and the second direction D2 may be perpendicular to each other and may correspond to the x-direction and the y-direction, respectively. For example, the platform 10 may be an XY platform having a repeatability accuracy of 100 nm or less.

[0048] In addition to the above differences, other components and / or features of the magnetic property measurement system 1000 according to this embodiment can be the same as those of the reference Figures 1 to 4 and FIG. 5A to FIG. 5D The corresponding components and / or features of the described magnetic property measurement system 1000 are substantially the same.

[0049] Hereinafter, a method of measuring magnetic properties using the magnetic property measurement system 1000 according to an embodiment of the inventive concept will be described.

[0050] Fig.10 is a flow chart illustrating a method for measuring magnetic properties according to some embodiments of the present inventive concept. Fig.11 is a plan view illustrating a sample used in a method for measuring magnetic properties according to some embodiments of the inventive concept. Fig.12 yes Fig.11 A cross-sectional view of a region of a sample, Fig.13 yes Fig.12 An enlarged view of portion 'A'. Fig.14 and Fig.15 1 and 2 are plan views and cross-sectional views, respectively, for illustrating a method for measuring magnetic properties according to some embodiments of the present invention. Figure 1 The magnetic property measurement system 1000 describes a method for measuring magnetic properties according to some embodiments of the present inventive concept.

[0051] Reference Figure 1 , Fig.10 and Fig.11 , a sample S including a magnetic tunnel junction pattern may be loaded on Figure 1 (or Figure 6 ) is placed on a platform 10 of a magnetic property measurement system 1000 (S100). The sample S may include a substrate 100 including a plurality of chip regions 200. The substrate 100 may be a semiconductor substrate including silicon, silicon on insulator (SOI), silicon germanium (SiGe), germanium (Ge), or gallium arsenic (GaAs). Each chip region 200 may include a storage region on which a storage element is provided.

[0052] Reference Fig.12 and Fig.13 , a wiring structure 125 may be provided on each chip region 200 of the substrate 100. The wiring structure 125 may include a conductive line 120 spaced apart from the substrate 100 and a contact 122 connected to the conductive line 120. The conductive line 120 may be electrically connected to the substrate 100 through the contact 122. The conductive line 120 and the contact 122 may include a metal material. For example, the conductive line 120 and the contact 122 may include copper (Cu). A first interlayer insulating layer 110 may be provided on each chip region 200 of the substrate 100 to cover or surround the wiring structure 125. The first interlayer insulating layer 110 may include at least one of an oxide layer, a nitride layer, or a nitride oxide layer.

[0053] The second interlayer insulating layer 130 may be provided on the first interlayer insulating layer 110, and the bottom electrode contacts 132 may be provided in the second interlayer insulating layer 130. Each bottom electrode contact 132 may pass through the second interlayer insulating layer 130 to be connected to a corresponding one of the conductive lines 120. The second interlayer insulating layer 130 may include at least one of an oxide layer, a nitride layer, or an oxynitride layer, and the bottom electrode contact 132 may include at least one of a doped semiconductor material (e.g., doped silicon), a metal (e.g., tungsten, titanium, or tantalum), a conductive metal nitride (e.g., titanium nitride, tantalum nitride, or tungsten nitride), or a metal-semiconductor compound (e.g., metal silicide).

[0054] A magnetic tunnel junction pattern MTJ may be provided on the second interlayer insulating layer 130. The magnetic tunnel junction patterns MTJ may be spaced apart from each other laterally on each chip region 200 of the substrate 100. In other words, the magnetic tunnel junction patterns MTJ may be spaced apart from each other in a direction parallel to the top surface or upper surface 100U of the substrate 100. The magnetic tunnel junction patterns MTJ may be connected to the bottom electrode contacts 132, respectively. A bottom electrode BE may be provided between each magnetic tunnel junction pattern MTJ and each bottom electrode contact 132. A top electrode TE may be provided on each magnetic tunnel junction pattern MTJ and may be spaced apart from the bottom electrode BE, with each magnetic tunnel junction pattern MTJ interposed therebetween. The bottom electrode BE and the top electrode TE may include a conductive material. For example, the bottom electrode BE and the top electrode TE may include a conductive metal nitride (e.g., titanium nitride or tantalum nitride).

[0055] Each magnetic tunnel junction pattern MTJ may include a first magnetic pattern 140, a second magnetic pattern 160, and a tunnel barrier pattern 150 disposed between the first magnetic pattern 140 and the second magnetic pattern 160. One of the first magnetic pattern 140 and the second magnetic pattern 160 may be a reference layer whose magnetization direction is fixed in one direction, and the other of the first magnetic pattern 140 and the second magnetic pattern 160 may be a free layer whose magnetization direction is switchable between stable magnetic states. The magnetization direction MD1 of the first magnetic pattern 140 and the magnetization direction MD2 of the second magnetic pattern 160 may be substantially perpendicular to the interface between the first magnetic pattern 140 and the tunnel barrier pattern 150. The magnetization direction MD1 of the first magnetic pattern 140 and the magnetization direction MD2 of the second magnetic pattern 160 may be substantially perpendicular to the top surface 100U of the substrate 100. Fig.13 1 shows an embodiment in which the first magnetic pattern 140 is a reference layer having a magnetization direction MD1 fixed in one direction and the second magnetic pattern 160 is a free layer having a changeable magnetization direction MD2. However, embodiments of the inventive concept are not limited thereto. In some embodiments, Fig.13 Differently, the first magnetic pattern 140 may be a free layer having a changeable magnetization direction, and the second magnetic pattern 160 may be a reference layer having a magnetization direction fixed in one direction.

[0056] Each of the first magnetic pattern 140 and the second magnetic pattern 160 may include at least one of an intrinsic perpendicular magnetic material or a non-intrinsic perpendicular magnetic material. The intrinsic perpendicular magnetic material may include a material having a perpendicular magnetization property even without an external factor. The intrinsic perpendicular magnetic material may include at least one perpendicular magnetic material (e.g., CoFeTb, CoFeGd, or CoFeDy), for example, having L1 0A vertical magnetic material with a hexagonal close-packed (HCP) lattice structure, a CoPt alloy, or a vertical magnetic structure. 0 The vertical magnetic material of the structure may include L1 0 FePt with L1 0 FePd with L1 0 CoPd of structure, or with L1 0 At least one of the CoPt of the structure. The perpendicular magnetic structure may include alternating and repeatedly stacked magnetic layers and non-magnetic layers. 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" represents the number of double layers. The non-intrinsic perpendicular magnetic material may include a material having an intrinsic horizontal magnetization characteristic but having a perpendicular magnetization characteristic due to external factors. For example, the non-intrinsic perpendicular magnetic material may have a perpendicular magnetization characteristic by the magnetic anisotropy caused by the junction of the tunnel barrier pattern 150 and the first magnetic pattern 140 (or the second magnetic pattern 160). The non-intrinsic perpendicular magnetic material may include, for example, CoFeB. The tunnel barrier pattern 150 may include at least one of magnesium oxide (MgO), titanium oxide (TiO), aluminum oxide (AlO), magnesium zinc oxide (MgZnO), magnesium boron oxide (MgBO), titanium nitride (TiN), or vanadium nitride (VN).

[0057] The sample S may include a substrate 100 and a magnetic tunnel junction pattern MTJ provided on the substrate 100. The magnetic tunnel junction pattern MTJ may be a perpendicular magnetic tunnel junction pattern in which the first magnetic pattern 140 and the second magnetic pattern 160 have magnetization directions MD1 and MD2 perpendicular to a plane (e.g., an interface between the first magnetic pattern 140 and the tunnel barrier pattern 150). Figure 1 (or Figure 6 ) may be a polar MOKE measurement system and may be used to measure the perpendicular magnetic properties of a perpendicular magnetic tunnel junction pattern MTJ.

[0058] Reference Figure 1 , Fig.10 and Fig.14 , a sample S including a magnetic tunnel junction pattern MTJ may be loaded on the platform 10 (S100). The sample S may be fixed on the platform 10 by vacuum (S110). The platform 10 may fix the sample S on the surface of the platform 10 by extracting or sucking air through the plurality of holes PH.

[0059] By horizontally moving the platform 10 in a first direction D1 (e.g., x direction) and / or a second direction D2 (e.g., y direction) parallel to the top surface SU of the sample S, the measurement target area RT of the sample S can be moved to the light irradiation area RF (S120). The light irradiation area RF may be a predetermined area in the chamber 500, to which the incident light Li is irradiated. The measurement target area RT may be a specific area of ​​the top surface SU of the sample S. For example, the center of the top surface SU of the sample S may correspond to the origin of the xy coordinate system, and the measurement target area RT of the top surface SU of the sample S may be represented by coordinate values ​​(x1, y1). Fig.14 , an xy coordinate system is shown on the top surface SU of the sample S. However, this is provided only to help understand the embodiments and is not intended to limit the inventive concept. In the initial state, the light irradiation area RF may overlap with the center of the top surface SU of the sample S. In this case, the platform 10 may move a distance of (-x1, -y1), and thus the measurement target area RT may be moved to overlap or align with the light irradiation area RF.

[0060] Reference Figure 1 , Fig.10 and Fig.15 , a magnetic field H perpendicular to one surface of the sample S may be applied to the sample S (S130). The magnetic field H may be perpendicular to the top surface SU of the sample S, and the top surface SU of the sample S may correspond to the top surface 100U of the substrate 100. In other words, the magnetic field H may be applied perpendicular to the top surface 100U of the substrate 100, and thus the first magnetic pattern 140 and the second magnetic pattern 160 may have a magnetization direction substantially perpendicular to the top surface 100U of the substrate 100. In other words, the magnetic tunnel junction pattern MTJ may have a perpendicular magnetic property.

[0061] Since the measurement target region RT overlaps with the light irradiation region RF, the incident light Li may be irradiated to the measurement target region RT of the sample S (S140). The incident light Li may be irradiated substantially perpendicular to the top surface 100U of the substrate 100. However, embodiments of the inventive concept are not limited thereto. In some embodiments, Fig.15 Differently, the incident light Li may be obliquely irradiated to the top surface 100U of the substrate 100. The incident light Li may be polarized by the polarizer 55 and then may be irradiated to the measurement target region RT.

[0062] Polarization of the reflected light Lr reflected from the measurement target region RT of the sample S may be detected (S150). The reflected light Lr may be polarized by the analyzer 75 and may be received by the detector 70 through the analyzer 75. The detector 70 may detect polarization of the reflected light Lr.

[0063] The reflected light Lr may include signal polarized light reflected from the magnetic tunnel junction pattern MTJ, and noise polarized light reflected from a lower pattern (e.g., a conductive line 120) below the magnetic tunnel junction pattern MTJ. For example, the conductive line 120 may extend in a direction parallel to the top surface 100U of the substrate 100, and the polarization direction ND of the noise polarized light may be substantially parallel to the direction in which the conductive line 120 extends. The polarization direction ND of the noise polarized light may be substantially perpendicular to the polarization axis PA of the analyzer 75. Therefore, the noise polarized light in the reflected light Lr may be blocked by the analyzer 75, while the signal polarized light in the reflected light Lr may pass through the analyzer 75 and then may be received by the detector 70.

[0064] If the platform 10 rotates, the sample S may rotate about a rotation axis that is parallel to a normal line perpendicular to a top surface SU of the sample S (e.g., a top surface 100U of the substrate 100). In this case, the polarization direction NDr of the noise polarized light may be tilted relative to the polarization axis PA of the analyzer 75. Therefore, at least a portion of the noise polarized light may pass through the analyzer 75 and may then be received by the detector 70. Therefore, the noise of the magnetic property measurement system 1000 may increase. In other words, it may be difficult to measure the effective magnetic properties of the magnetic tunnel junction pattern MTJ.

[0065] However, according to an embodiment of the present invention, the platform 10 may be an XY platform configured to move horizontally in a first direction D1 (e.g., x direction) and a second direction D2 (e.g., y direction) parallel to the top surface SU of the sample S. In this case, it may not be necessary to rotate the platform 10 to move the measurement target area RT of the sample S to the light irradiation area RF. Therefore, the polarization direction ND of the noise polarized light reflected from the measurement target area RT of the sample S may be substantially perpendicular to the polarization axis PA of the analyzer 75. As a result, the noise polarized light in the reflected light Lr may be blocked by the analyzer 75, and thus the noise of the magnetic property measurement system 1000 may be reduced to easily measure the effective magnetic properties of the magnetic tunnel junction pattern MTJ. In other words, since the platform 10 is an XY platform, the effective magnetic properties of the magnetic tunnel junction pattern MTJ may be measured on various regions of the sample S.

[0066] In addition, the stage 10 may be configured to fix the sample S on the stage 10 by using a vacuum. Therefore, the magnetic properties of the magnetic tunnel junction pattern MTJ in the sample S may be stably measured despite the movement of the stage 10.

[0067] Information about the perpendicular magnetic properties of the magnetic tunnel junction pattern MTJ may be obtained by analyzing the polarization of the reflected light Lr (S160). For example, obtaining information about the perpendicular magnetic properties of the magnetic tunnel junction pattern MTJ may include generating a hysteresis curve of the magnetic tunnel junction pattern MTJ. Information about the perpendicular magnetic properties of the magnetic tunnel junction pattern MTJ may be obtained through the hysteresis curve. For example, information about the perpendicular magnetic properties of the magnetic tunnel junction pattern MTJ may include the exchange magnetic field (Hex), coercive force (Hc) and / or dispersion of coercive force (Hc) of the magnetic tunnel junction pattern MTJ in the unit chip.

[0068] Fig.16 is a flowchart illustrating a method of manufacturing a magnetic memory device using a magnetic property measurement system according to some embodiments of the inventive concept. Figures 17 to 19 2 is a cross-sectional view illustrating a method of manufacturing a magnetic memory device using a magnetic property measurement system according to some embodiments of the inventive concept.

[0069] Reference Fig.16 and Fig.17 , a selection element may be formed on the substrate 100. The substrate 100 may be a semiconductor substrate including silicon, silicon on insulator (SOI), silicon germanium (SiGe), germanium (Ge) or gallium arsenide (GaAs). The selection element may be a field effect transistor or a diode. Afterwards, a wiring structure 125 may be formed on the substrate 100 (S200). The wiring structure 125 may be electrically connected to the substrate 100. The wiring structure 125 may include a conductive line 120 spaced apart from the substrate 100 and a contact 122 connected to the conductive line 120. The conductive line 120 may be electrically connected to the substrate 100 through the contact 122. At least one of the conductive lines 120 may be electrically connected to one terminal of the corresponding selection element through the corresponding contact 122. The conductive line 120 and the contact 122 may include a metal material. For example, the conductive line 120 and the contact 122 may include copper (Cu). The first interlayer insulating layer 110 may be formed on the substrate 100 to cover or surround the selection element and the wiring structure 125. The first interlayer insulating layer 110 may be formed of a single layer or a multilayer including at least one of an oxide layer, a nitride layer, or an oxynitride layer.

[0070] Bottom electrode contacts 132 may be formed on the wiring structure 125 (S210). Each bottom electrode contact 132 may be electrically connected to one terminal of a corresponding selection element through a corresponding conductive line 120. The bottom electrode contact 132 may include at least one of a doped semiconductor material (e.g., doped silicon), a metal (e.g., tungsten, titanium, and / or tantalum), a conductive metal nitride (e.g., titanium nitride, tantalum nitride, and / or tungsten nitride), or a metal-semiconductor compound (e.g., metal silicide). A second interlayer insulating layer 130 may be formed on the first interlayer insulating layer 110, and the second interlayer insulating layer 130 may cover or surround the bottom electrode contact 132. The second interlayer insulating layer 130 may be formed of a single layer or multiple layers including at least one of an oxide layer, a nitride layer, or an oxynitride layer.

[0071] A bottom electrode layer BEL and a magnetic tunnel junction layer MTJL covering the bottom electrode contact 132 may be formed on the second interlayer insulating layer 130 (S220). The bottom electrode layer BEL may be disposed between the second interlayer insulating layer 130 and the magnetic tunnel junction layer MTJL. For example, the bottom electrode layer BEL may include a conductive metal nitride (e.g., titanium nitride or tantalum nitride). The magnetic tunnel junction layer MTJL may include a first magnetic layer 142, a tunnel barrier layer 152, and a second magnetic layer 162 sequentially stacked on the bottom electrode layer BEL. Each of the first magnetic layer 142 and the second magnetic layer 162 may include at least one of an intrinsic vertical magnetic material or an extrinsic vertical magnetic material as described above. The tunnel barrier layer 152 may include at least one of magnesium oxide (MgO), titanium oxide (TiO), aluminum oxide (AlO), magnesium zinc oxide (MgZnO), magnesium boron oxide (MgBO), titanium nitride (TiN), or vanadium nitride (VN).

[0072] The perpendicular magnetic properties of the magnetic tunnel junction layer MTJL can be measured (S230). Figure 1 (or Figure 6 )'s magnetic property measurement system 1000 measures the perpendicular magnetic properties of the magnetic tunnel junction layer MTJL.

[0073] Specifically, a sample S may be prepared, the sample S including a substrate 100 having a magnetic tunnel junction layer MTJL. Figure 1 and Fig.10 As described, the sample S can be loaded into Figure 1 or Figure 6The platform 10 of the magnetic property measurement system 1000 is placed on the platform 10 (S100), and the sample S can be fixed on the platform 10 by vacuum (S110). By horizontally moving the platform 10 in a first direction D1 (e.g., x direction) and / or a second direction D2 (e.g., y direction) parallel to the top surface SU of the sample S, the measurement target area RT of the sample S can be moved to the light irradiation area RF (S120). A magnetic field H perpendicular to the top surface SU of the sample S can be applied to the sample S (S130). Incident light Li can be irradiated to the measurement target area RT of the sample S (S140), and the polarization of the reflected light Lr reflected from the measurement target area RT of the sample S can be detected (S150). Information about the perpendicular magnetic properties of the magnetic tunnel junction layer MTJL can be obtained by analyzing the polarization of the reflected light Lr (S160). Obtaining information about the perpendicular magnetic properties of the magnetic tunnel junction layer MTJL may include generating a hysteresis curve of the magnetic tunnel junction layer MTJL. Information about the perpendicular magnetic properties of the magnetic tunnel junction layer MTJL can be obtained by the hysteresis curve. For example, the information about the perpendicular magnetic properties of the magnetic tunnel junction layer MTJL may include an exchange magnetic field (Hex), a coercive force (Hc), and / or a dispersion of the coercive force (Hc) of the magnetic tunnel junction layer MTJL in the unit chip.

[0074] Reference Fig.16 and Fig.18 , it can be determined whether the measured perpendicular magnetic properties of the magnetic tunnel junction layer MTJL are within the allowable range (S240). When the measured perpendicular magnetic properties are outside the allowable range, a warning can be generated (S250). When the measured perpendicular magnetic properties are within the allowable range, a conductive mask pattern 165 can be formed on the magnetic tunnel junction layer MTJL. The conductive mask pattern 165 can define an area in which a magnetic tunnel junction pattern is to be formed. For example, the conductive mask pattern 165 may include a conductive metal nitride (e.g., titanium nitride or tantalum nitride).

[0075] Reference Fig.15 and Fig.16 , the magnetic tunnel junction layer MTJL and the bottom electrode layer BEL may be sequentially patterned using the conductive mask pattern 165 as an etching mask to form a magnetic tunnel junction pattern MTJ and a bottom electrode BE (S260). The conductive mask pattern 165 may be used as a top electrode TE, respectively. Each magnetic tunnel junction pattern MTJ may include a first magnetic pattern 140, a tunnel barrier pattern 150, and a second magnetic pattern 160 sequentially stacked on each bottom electrode BE. The magnetic tunnel junction patterns MTJ may be spaced apart from each other in a direction parallel to the top surface 100U of the substrate 100, and the bottom electrodes BE may be provided under the magnetic tunnel junction patterns MTJ, respectively.

[0076] The perpendicular magnetic properties of the magnetic tunnel junction pattern MTJ can be measured (S270). Figure 1(or Figure 6 ) is used to measure the perpendicular magnetic properties of the magnetic tunnel junction pattern MTJ.

[0077] Specifically, a sample S may be prepared, the sample S including a substrate 100 having a magnetic tunnel junction pattern MTJ. Figure 1 and Fig.10 As described above, the sample S can be loaded on Figure 1 or Figure 6 The platform 10 of the magnetic property measurement system 1000 is placed on the platform 10 (S100), and the sample S can be fixed on the platform 10 by vacuum (S110). By horizontally moving the platform 10 in a first direction D1 (e.g., x direction) and / or a second direction D2 (e.g., y direction) parallel to the top surface SU of the sample S, the measurement target area RT of the sample S can be moved to the light irradiation area RF (S120). A magnetic field H perpendicular to the top surface SU of the sample S can be applied to the sample S (S130). Incident light Li can be irradiated to the measurement target area RT of the sample S (S140), and the polarization of the reflected light Lr reflected from the measurement target area RT of the sample S can be detected (S150). Information about the perpendicular magnetic properties of the magnetic tunnel junction pattern MTJ can be obtained by analyzing the polarization of the reflected light Lr (S160). Obtaining information about the perpendicular magnetic properties of the magnetic tunnel junction pattern MTJ may include generating a hysteresis curve of the magnetic tunnel junction pattern MTJ. Information about the perpendicular magnetic properties of the magnetic tunnel junction pattern MTJ can be obtained by the hysteresis curve. For example, the information about the perpendicular magnetic properties of the magnetic tunnel junction pattern MTJ may include an exchange magnetic field (Hex), a coercive force (Hc), and / or a dispersion of the coercive force (Hc) of the magnetic tunnel junction pattern MTJ in a unit chip.

[0078] Reference Fig.16 and Fig.19, it can be determined whether the measured perpendicular magnetic properties of the magnetic tunnel junction pattern MTJ are within the allowable range (S280). When the measured perpendicular magnetic properties are outside the allowable range, a warning can be generated (S290). When the measured perpendicular magnetic properties are within the allowable range, a subsequent process can be performed (S300). Specifically, a protective layer 170 can be formed on the second interlayer insulating layer 130 and can cover or surround the sidewalls of the magnetic tunnel junction pattern MTJ and the sidewalls of the bottom electrode BE. The protective layer 170 can also cover or surround the sidewalls of the top electrode TE. The protective layer 170 may include, for example, silicon nitride. The third interlayer insulating layer 180 may be formed on the second interlayer insulating layer 130 and may cover or surround the magnetic tunnel junction pattern MTJ, the bottom electrode BE, and the top electrode TE. The protective layer 170 may be disposed between the third interlayer insulating layer 180 and each magnetic tunnel junction pattern MTJ, between the third interlayer insulating layer 180 and each bottom electrode BE, and between the third interlayer insulating layer 180 and each top electrode TE. In addition, the protective layer 170 may extend between the third interlayer insulating layer 180 and the top surface of the second interlayer insulating layer 130 disposed between the magnetic tunnel junction patterns MTJ. The third interlayer insulating layer 180 may be formed to fill the space between the magnetic tunnel junction patterns MTJ. The third interlayer insulating layer 180 may include at least one of an oxide layer, a nitride layer, or an oxynitride layer. The bit line 190 may be formed on the third interlayer insulating layer 180. Each magnetic tunnel junction pattern MTJ may be connected to a corresponding one of the bit lines 190. The bit line 190 may include at least one of a metal (e.g., titanium, tantalum, copper, aluminum, or tungsten) or a conductive metal nitride (e.g., titanium nitride or tantalum nitride).

[0079] Fig. 20 is a circuit diagram illustrating a unit memory cell of a magnetic memory device manufactured according to some embodiments of the inventive concept.

[0080] Reference Fig. 20, the unit memory cell MC may include a memory element ME and a selection element SE connected in series with each other. The memory element ME may be connected between the bit line BL and the selection element SE. The selection element SE may be connected between the memory element ME and the source line SL and may be controlled by the word line WL. The memory element ME may include a magnetic tunnel junction pattern MTJ, which includes a first magnetic pattern 140 and a second magnetic pattern 160 and a tunnel barrier pattern 150 disposed between the first magnetic pattern 140 and the second magnetic pattern 160. One of the first magnetic pattern 140 and the second magnetic pattern 160 may be a reference layer (having a magnetization direction that is fixed regardless of an external magnetic field in a use environment), and the other of the first magnetic pattern 140 and the second magnetic pattern 160 may be a free layer (whose magnetization direction is changeable by an external magnetic field or a spin torque of electrons in a programming current). The resistance of the magnetic tunnel junction pattern MTJ when the magnetization directions of the reference layer and the free layer are antiparallel to each other or not parallel to each other may be much greater than the resistance of the magnetic tunnel junction pattern MTJ when the magnetization directions of the reference layer and the free layer are parallel to each other. In other words, the resistance of the magnetic tunnel junction pattern MTJ can be adjusted by changing the magnetization direction of the free layer. Therefore, by using the resistance difference according to the magnetization directions of the reference layer and the free layer, logic data can be stored in the memory element ME of the unit memory cell MC.

[0081] According to an embodiment of the inventive concept, the stage 10 may be configured as an XY stage, and thus the effective magnetic properties of the magnetic tunnel junction pattern MTJ may be measured on various regions of the sample S. The stage 10 may be configured to fix the sample S on the stage 10 by using a vacuum. Therefore, although the stage 10 moves, the magnetic properties of the magnetic tunnel junction pattern MTJ in the sample S may be stably measured.

[0082] Furthermore, in the process of manufacturing a magnetic memory device, the magnetic properties of the magnetic tunnel junction pattern MTJ can be advantageously monitored using the magnetic property measurement system 1000. Therefore, a method of manufacturing a magnetic memory device can be provided, which can improve mass production and quality stability.

[0083] Although the inventive concept has been described with reference to example embodiments, it will be apparent to those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the inventive concept. Therefore, it should be understood that the above embodiments are not restrictive but illustrative. Therefore, the scope of the inventive concept will be determined by the broadest permissible interpretation of the claims and their equivalents, and should not be limited or defined by the foregoing description.

[0084] This patent application claims the priority benefit of Korean Patent Application No. 10-2018-0125889 filed on October 22, 2018 in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference in its entirety.

Claims

1. A magnetic property measurement system, comprising: a platform configured to hold a sample; and a magnetic structure disposed above the platform, The platform includes: The main part; a magnetic portion adjacent to the body portion; a plurality of apertures defined in the body portion; a light source configured to illuminate a surface of the sample with incident light; and a detector configured to detect polarization of light reflected from the sample, wherein the sample is between the magnetic portion of the platform and the magnetic structure, wherein the magnetic portion and the magnetic structure of the platform are configured to apply a magnetic field to the sample that is perpendicular to the one surface of the sample, and The stage is configured to move horizontally in a first direction and a second direction parallel to the one surface of the sample and perpendicular to each other to move a measurement target area of ​​the sample to a light irradiation area.

2. The magnetic property measurement system according to claim 1, wherein each of the plurality of holes is connected to a vacuum line disposed in the main body portion, and The platform is configured to secure the sample on the platform by drawing air through the plurality of holes.

3. The magnetic property measurement system according to claim 2, further comprising: Connect a vacuum pump to the vacuum line.

4. The magnetic property measurement system according to claim 2, wherein the magnetic portion is disposed on the main body portion, and The plurality of holes penetrate the magnetic portion. 5 . The magnetic property measurement system according to claim 4 , wherein the magnetic portion is a coating coated on the top surface of the main body portion. 6 . The magnetic property measurement system according to claim 4 , wherein the platform is configured such that the sample is placed on a top surface of the magnetic portion.

7. The magnetic property measurement system according to claim 2, wherein the magnetic portion is disposed in the main body portion, and The plurality of holes penetrate the magnetic portion. 8 . The magnetic properties measuring system according to claim 7 , wherein the platform is configured such that the sample is placed on a top surface of the main body portion.

9. The magnetic property measurement system according to claim 1, wherein the magnetic structure comprises: a pole shoe; and a coil surrounding an outer peripheral surface of the pole shoe.

10. The magnetic property measurement system according to claim 1, further comprising: Polarizers and analyzers, wherein the incident light is irradiated to the sample through the polarizer, and The reflected light passes through the analyzer and is received at the detector.

11. The magnetic property measurement system according to claim 1, further comprising: Controller, The controller generates a hysteresis curve based on data obtained from the detector.

12. A method for measuring magnetic properties, the method comprising: Loading the sample on the platform; securing the sample to the platform by applying a vacuum; moving a measurement target area of ​​the sample to a light irradiation area by horizontally moving the stage in a first direction and a second direction that are parallel to a top surface of the sample and perpendicular to each other; applying a magnetic field to the sample perpendicular to the top surface of the sample; irradiating incident light to the measurement target area of ​​the sample; as well as detecting polarization of light reflected from the measurement target area of ​​the sample, The platform includes: The main part; a magnetic portion adjacent to the body portion; and a plurality of apertures defined in the body portion, wherein the sample is between the magnetic portion of the platform and a magnetic structure disposed above the platform, The magnetic field is generated by the magnetic portion of the platform and the magnetic structure.

13. The method of claim 12, wherein the sample comprises: substrate; and magnetic tunnel junction patterns laterally spaced apart from each other on the substrate.

14. The method according to claim 13, further comprising: applying a magnetic field to the sample perpendicular to the top surface of the sample; as well as Information on the perpendicular magnetic properties of the magnetic tunnel junction pattern is obtained by analyzing polarization of light reflected from the measurement target area of ​​the sample.

15. The method of claim 14, wherein obtaining information about the perpendicular magnetic properties of the magnetic tunnel junction pattern comprises: A hysteresis curve of the magnetic tunnel junction pattern is generated by using the polarized magneto-optical Kerr effect.

16. The method of claim 12, wherein the platform comprises: The main part; a magnetic portion adjacent to the body portion; and a plurality of apertures defined in the body portion, The platform is configured to secure the sample on the platform by drawing air through the plurality of holes.

17. The method according to claim 16, further comprising: applying a magnetic field to the sample perpendicular to the top surface of the sample, The magnetic field is generated by the magnetic portion of the platform and a magnetic structure disposed above the platform.

18. The method of claim 16, wherein the plurality of holes penetrate the magnetic portion, and: (i) the magnetic portion is disposed on the body portion, and loading the sample onto the platform comprises placing the sample on a top surface of the magnetic portion, or (ii) the magnetic portion is disposed in the body portion, and loading the sample on the platform includes placing the sample on a top surface of the body portion.

19. A method for manufacturing a magnetic memory device, the method comprising: forming a magnetic tunnel junction layer on a substrate; patterning the magnetic tunnel junction layer to form a magnetic tunnel junction pattern; measuring the magnetic properties of the magnetic tunnel junction pattern; as well as Determine whether the measured magnetic properties are within the allowable range, Wherein measuring the magnetic property of the magnetic tunnel junction pattern comprises: Loading the substrate onto a platform in a magnetic property measurement system; securing the substrate to the platform by applying a vacuum; moving a measurement target area of ​​the substrate to a light irradiation area by horizontally moving the stage in a first direction and a second direction that are parallel to a top surface of the substrate and perpendicular to each other; applying a magnetic field perpendicular to the top surface of the substrate to the substrate; irradiating incident light to the measurement target area of ​​the substrate; and detecting polarization of light reflected from the measurement target area of ​​the substrate, The platform includes: The main part; a magnetic portion adjacent to the body portion; and a plurality of apertures defined in the body portion, wherein the substrate is between the magnetic portion of the platform and a magnetic structure disposed above the platform, The magnetic field is generated by the magnetic portion of the platform and the magnetic structure.

20. The method of claim 19, wherein the magnetic property measurement system is a polarized magneto-optical Kerr effect measurement system.

21. The method of claim 20, wherein measuring the magnetic property of the magnetic tunnel junction pattern further comprises: applying a magnetic field perpendicular to the top surface of the substrate to the substrate; as well as By analyzing polarization of light reflected from the measurement target region of the substrate, information on perpendicular magnetic properties of the magnetic tunnel junction pattern is obtained.

22. The method of claim 21 , wherein obtaining information about the perpendicular magnetic properties of the magnetic tunnel junction pattern comprises: A hysteresis curve of the magnetic tunnel junction pattern is generated.

23. The method of claim 19, further comprising: When the measured magnetic property is within an allowable range, a protection layer and an interlayer insulating layer covering the magnetic tunnel junction pattern are formed on the substrate.

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