Magnetic film, magnetoresistive element and magnetic memory

Abstract

To provide a magnetic film, a magnetoresistive element, and a magnetic memory that maintain the vertical magnetic anisotropy of a magnetic layer in a fixed layer and enables strong pinning even by annealing after a protective film is formed, while taking advantage of a top pin structure and a bottom pin structure.SOLUTION: A fixed layer of a magnetic film has a basic configuration in which a first magnetic layer 21, a first non-magnetic layer 31, a first Pt layer 41, and a second magnetic layer 22 are arranged adjacent to each other in this order. The magnetization directions of the first magnetic layer 21 and the second magnetic layer 22 are both perpendicular to the film surface, and an antiferromagnetic bond is formed between the first magnetic layer 21 and the second magnetic layer 22.SELECTED DRAWING: Figure 22

Description

[Technical Field]

[0001] The present invention relates to a magnetic film, a magnetoresistive element including the magnetic film, and a magnetic memory including the magnetoresistive element. [Background technology]

[0002] MRAM (Magnetic Random Access Memory) is a non-volatile memory that uses MTJ (Magnetic Tunnel Junction). MRAM consumes no power during standby, has high-speed operation and high write endurance, and its memory size can be miniaturized. Therefore, it is attracting attention as a next-generation embedded memory for logic integrated circuits.

[0003] The magnetoresistive element used in MRAM has a basic structure in which a barrier layer is sandwiched between a recording layer and a reference layer (fixed layer). Bit information recorded in the magnetic layer (recording layer) of MRAM passes through the barrier layer and is read using the TMR (Tunnel Magnetoresistance) effect.

[0004] There are two methods for writing to the magnetic layer (recording layer): using a magnetic field or using an electric current. MRAMs that use the latter writing method include two-terminal types that write bit information to the magnetic layer (recording layer) using spin-transfer-torque (STT) induced magnetization reversal, and three-terminal types that write bit information to the magnetic layer (recording layer) using spin-orbit-torque (SOT) induced magnetization reversal.

[0005] In the STT-MRAM and SOT-MRAM, a magnetoresistive element having an MTJ is arranged with its electrode connected to a selection transistor. In the STT-MRAM, the drain of one selection transistor is connected to the lower electrode of one magnetoresistive element, and the upper electrode of the magnetoresistive element is connected to a bit line, respectively. When a current is supplied from each selection transistor to the magnetoresistive element, the magnetization reversal operation of the magnetic layer (recording layer) of the MTJ element is performed. In the SOT-MRAM, one bit is composed of two selection transistors and one magnetoresistive element, and when a current is supplied from the selection transistor to the heavy metal layer that is the lower wiring of the magnetoresistive element, the magnetization reversal operation of the magnetic layer (recording layer) of the MTJ element is performed. Examples of the selection transistor include a MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor).

[0006] The magnetoresistive element is classified into a top-pin structure, which has a recording layer, a barrier layer, and a fixed layer on a bottom electrode in this order, and a bottom-pin structure, which has a fixed layer, a barrier layer, and a recording layer on a bottom electrode in this order. The bottom electrode is connected to the drain of the select transistor.

[0007] Figure 1(a) shows an example of a top-pinned STT-MRAM, and Figure 1(b) shows an example of a bottom-pinned STT-MRAM. The magnetization direction of the pinned layer is fixed, but the magnetization of the recording layer is reversible. Figure 2 shows an example of a top-pin structure SOT-MRAM.

[0008] Here, due to the characteristics of the select transistor, when writing to the magnetoresistive effect element, there is an asymmetry in that the value of the drive current of the select transistor that can flow from the select transistor connected to the lower electrode of the magnetoresistive effect element in the direction of the magnetoresistive effect element is smaller than the value of the drive current of the select transistor that can flow from the magnetoresistive effect element in the direction of the select transistor. On the other hand, with regard to the magnetization reversal of the recording layer during writing to the magnetoresistive element, the value of the reversal current required to reverse the magnetization direction from a parallel state to an antiparallel state is greater than the value of the reversal current required to reverse the magnetization direction from an antiparallel state to a parallel state.

[0009] Therefore, if it is desired to effectively use the drive current of the selection transistor as a write current for the magnetoresistive element, it is preferable to align the direction in which the drive current value is large with the magnetization direction in which a large reversal current value is required. Figure 3(a) shows an example of a top-pin structure STT-MRAM connected to a select transistor (NMOS). Figure 3(b) shows the relationship between the magnitude of the drive current depending on the direction of the current during writing and the magnitude of the reversal current required depending on the direction of magnetization reversal in a top-pin MRAM. As mentioned above, due to the characteristics of the select transistor, the drive current that can flow from the MTJ to the drain is greater than the drive current that can flow from the drain to the MTJ. On the other hand, the reversal current required to reverse the magnetization of the recording layer from a parallel state to an antiparallel state is greater than the reversal current required to reverse from an antiparallel state to a parallel state. Therefore, in a top-pin structure MRAM, the correspondence in Figure 3(b) shows that the direction from the MTJ to the drain (the direction in which a large drive current can flow) and the magnetization direction of the recording layer (before reversal), which requires a large reversal current, are the same direction, and the drive current can be effectively used for magnetization reversal.

[0010] Next, Figure 4(a) shows an example in which a bottom-pin structure STT-MRAM is connected to a select transistor. Figure 4(b) shows the relationship between the magnitude of the drive current depending on the direction of the current during writing and the magnitude of the reversal current required depending on the direction of magnetization reversal in a bottom-pin MRAM. As mentioned above, due to the characteristics of the select transistor, the drive current that can flow from the MTJ to the drain is greater than the drive current that can flow from the drain to the MTJ. On the other hand, the reversal current required to reverse the magnetization of the recording layer from a parallel state to an antiparallel state is greater than the reversal current required to reverse from an antiparallel state to a parallel state. Therefore, in a bottom-pin MRAM, the correspondence in Figure 4(b) shows that the direction from the MTJ to the drain (the direction in which a large drive current can flow) and the magnetization direction of the recording layer (before reversal), which requires a large reversal current, are different directions, and it can be seen that the drive current cannot be fully utilized effectively for magnetization reversal.

[0011] As described above, the top-pin structure aligns the direction from the magnetoresistive element to the select transistor (the direction in which a large drive current can flow) with the parallel magnetization direction of the recording layer of the magnetoresistive element (the direction in which a large reversal current is required), thereby making it possible to effectively utilize the drive current of the select transistor and ensuring an appropriate margin in the current value. As a result, there is an advantage that the size of the select transistor can be reduced (see Non-Patent Document 1, etc.) In this respect, the top-pin structure is more advantageous than the bottom-pin structure. When a PMOS select transistor is used, a bottom pin structure is advantageous, as described in Non-Patent Document 2.

[0012] The fixed layer of an MTJ must also be sufficiently pinned to ensure accurate writing and reading from the recording layer. Key points for such pinning include enhancing antiferromagnetic coupling between the magnetic layers and the crystalline orientation of the magnetic layers. In this regard, the bottom-pinned structure can be said to be easier to pin because a thick underlayer (Pt layer) can be placed on the bottom electrode, and the crystalline orientation of the magnetic layer placed above it can be improved. On the other hand, the top-pin structure has the problem that it is not possible to place a thick Pt layer (underlayer) on top of the lower electrode / recording layer / barrier layer, so the magnetic layer of the fixed layer does not have sufficient crystalline orientation, making it difficult to achieve sufficient pinning. FIG. 34 shows a conventional example of a magnetoresistive effect element with a top pin structure, and FIG. 35 shows a conventional example of a magnetoresistive effect element with a bottom pin structure.

[0013] In addition to the various problems mentioned above, the pinned layer of the magnetoresistive element must be able to maintain sufficient pinning even after annealing at 300 to 400°C, which is performed during the manufacturing process of the magnetic memory. At the same time, if the magnetization direction of the recording layer of the MTJ is perpendicular to the film surface, it must also maintain perpendicular magnetization.

[0014] Here, we will explain the annealing process in the manufacture of magnetic memories using magnetoresistive elements. One example of memory manufacturing is a method in which a complementary metal-oxide semiconductor (CMOS) is fabricated on a substrate wafer, intermediate wiring for connection to the magnetoresistive elements is formed on the CMOS, a magnetic film is wired on top of the intermediate wiring, and the resulting structure is heat-treated. Then, a pattern of the magnetoresistive elements is created, the magnetoresistive elements are formed by etching, a protective film is formed, upper wiring is formed on the magnetoresistive elements, the resulting structure is cut into chips, and the chips are connected to a predetermined circuit board with wire-bonding metal wires, followed by resin sealing. A magnetic memory equipped with a magnetoresistive element having high element performance, such as a thermal stability index, requires annealing at approximately 300°C to 400°C after the protective film is formed to relieve stress or distortion in the magnetoresistive elements, the protective film, etc. (see Patent Document 1). [Prior art documents] [Patent documents]

[0015] [Patent Document 1] WO2018 / 043377A1 [Non-patent literature]

[0016] [Non-Patent Document 1] Young Min Lee, et. al., “Highly Scalable STT-MRAM with MTJs of Top-pinned Structure in 1T / 1MTJ Cell”, 2010 Symposium on VLSI Technology Digest of Technical Papers, 49-50, (2010) [Non-patent document 2] Hiroki Koike, et. al., “Wide operational margin capability of 1 kbit spin-transfer-torque memory array chip with 1-PMOS and 1-bottom-pin-magnetic-tunnel-junction type cell”, Jpn. J. Appl. Phys. 53, 04ED13 (2014) Summary of the Invention [Problem to be solved by the invention]

[0017] As described above, even after the annealing treatment at 300 to 400°C after the formation of the protective film in the magnetic memory manufacturing process, the antiferromagnetically coupled magnetic layer of the pinned layer is required to maintain perpendicular magnetic anisotropy and provide strong pinning. However, magnetoresistive effect elements with a top-pin structure, particularly those with a conventional pinned layer layer configuration, have had the problem of not being able to provide strong pinning, despite being advantageous in terms of the relationship between the direction of the drive current and the reversal current of the select transistor. In order to commercialize magnetic memories, the performance of magnetoresistive effect elements and the issues in the magnetic memory manufacturing process must be resolved simultaneously, and there was a need to develop a new layer configuration for the pinned layer that can maintain perpendicular magnetic anisotropy even after annealing treatment at around 400°C.

[0018] In view of the above circumstances, the present invention provides a magnetic film, a magnetoresistive element, and a magnetic memory that can maintain the perpendicular magnetic anisotropy of the magnetic layer, enhance crystalline orientation, and achieve strong pinning even after annealing treatment after forming a protective film. [Means for solving the problem]

[0019] In order to solve the above problem, the magnetic film of the present invention comprises a first magnetic layer (21), a first non-magnetic layer (31) provided adjacent to the first magnetic layer (21), a first Pt layer (41) provided adjacent to the first non-magnetic layer (31) on the side opposite to the first magnetic layer (21), and a second magnetic layer (22) provided adjacent to the first Pt layer (41) on the side opposite to the first non-magnetic layer (31), wherein the magnetization directions of the first magnetic layer (21) and the second magnetic layer (22) are both perpendicular to the film surface, and there is antiferromagnetic coupling between the first magnetic layer (21) and the second magnetic layer (22).

[0020] The first magnetic layer (21) and the second magnetic layer (22) preferably have an fcc(111) structure.

[0021] The first magnetic layer (21) and the second magnetic layer (22) may be made of Co.

[0022] In the X-ray diffraction spectrum, the first magnetic layer (21) and the second magnetic layer (22) preferably have a main peak of X-ray diffraction intensity when the angle 2θ, which is twice the angle of incidence of X-rays, is between 42° and 43°.

[0023] The first non-magnetic layer (31) is preferably made of Ir or Ru.

[0024] More preferably, the thickness of the Ir in the first non-magnetic layer (31) is 0.5±0.15 nm or 1.35±0.1 nm, and the thickness of the Ru is 0.9±0.2 nm or 0.4±0.15 nm.

[0025] The thickness of the second magnetic layer (22) is preferably greater than the thickness of the first Pt layer (41).

[0026] A first adjustment layer (A1) may be disposed on the side of the first magnetic layer (21) opposite to the first non-magnetic layer (31), and the first adjustment layer (A1) may contain Pt.

[0027] a second non-magnetic layer (32) provided adjacent to the second magnetic layer (22) on a side opposite to the first Pt layer (41); a second Pt layer (42) provided adjacent to the second non-magnetic layer (32) on a side opposite to the second magnetic layer (22); and a third magnetic layer (23) provided adjacent to the second Pt layer (42) on a side opposite to the second non-magnetic layer (32); Preferably, the magnetization direction of the third magnetic layer (23) is perpendicular to the film surface, and the second magnetic layer (22) and the third magnetic layer (23) are antiferromagnetically coupled to each other.

[0028] The magnetic recording medium further includes a third non-magnetic layer (33) provided adjacent to the third magnetic layer (23) on the side opposite to the second Pt layer (42), a third Pt layer (43) provided adjacent to the third non-magnetic layer (33) on the side opposite to the third magnetic layer (23), and a fourth magnetic layer (24) provided adjacent to the third Pt layer (43) on the side opposite to the third non-magnetic layer (33), wherein the magnetization direction of the fourth magnetic layer (24) is perpendicular to the film surface, and it is preferable that there is antiferromagnetic coupling between the third magnetic layer (23) and the fourth magnetic layer (24).

[0029] a fourth non-magnetic layer (34) provided adjacent to the fourth magnetic layer (24) on the side opposite to the third Pt layer (43); a fourth Pt layer (44) provided adjacent to the fourth non-magnetic layer (34) on the side opposite to the fourth magnetic layer (24); and a fifth magnetic layer (25) provided adjacent to the fourth Pt layer (44) on the side opposite to the fourth non-magnetic layer (34); Preferably, the magnetization direction of the fifth magnetic layer (25) is perpendicular to the film surface, and the fourth magnetic layer (24) and the fifth magnetic layer (25) are antiferromagnetically coupled to each other.

[0030] The magnetoresistive effect element of the present invention comprises a first fixed layer (P1) including the above-mentioned magnetic film, and a first barrier layer (B1), wherein the first barrier layer (B1) is arranged on the first adjustment layer (A1) side of the first fixed layer (P1), and the first adjustment layer (A1) is a Co / Pt multilayer film.

[0031] The magnetoresistive effect element of the present invention comprises a second fixed layer (P2) including the above-mentioned magnetic film, and a second barrier layer (B2), wherein the second barrier layer (B2) is arranged on the opposite side of the second fixed layer (P2) from the first adjustment layer (A1), and the first adjustment layer (A1) is a layer containing Pt as a main element.

[0032] The optical recording medium may comprise the first fixed layer (P1), the first barrier layer (B1), a recording layer (F1), the second barrier layer (B2), and the second fixed layer (P2), wherein the first barrier layer (B1) is provided adjacent to the first fixed layer (P1) on the side of the first adjustment layer (A1), the recording layer (F1) is provided adjacent to the first barrier layer (B1) on the opposite side of the first fixed layer (P1), the second barrier layer (B2) is provided adjacent to the recording layer (F1) on the opposite side of the first barrier layer (B1), and the second fixed layer (P2) is provided adjacent to the second barrier layer (B2) on the opposite side of the recording layer (F1).

[0033] A magnetic memory according to the present invention includes the above magnetoresistive element. Furthermore, the magnetic film, magnetoresistive effect element, and magnetic memory of the present invention are characterized in that the stacking order of the first non-magnetic layer (31) and the first Pt layer (41), and / or the stacking order of the second non-magnetic layer (32) and the second Pt layer (42), and / or the stacking order of the third non-magnetic layer (33) and the third Pt layer (43), and / or the stacking order of the fourth non-magnetic layer (34) and the fourth Pt layer (44), contained in the magnetic film, magnetoresistive effect element, and magnetic memory, are reversed. [Effects of the Invention]

[0034] According to the present invention, it is possible to provide a magnetic film capable of maintaining the antiferromagnetic coupling of the magnetic layer in the pinned layer, even when an annealing treatment is performed at about 300°C to 400°C after forming a protective film in order to relieve stress or distortion in the magnetoresistive element, protective film, etc. after forming a protective film in the manufacture of a magnetic memory using a magnetoresistive element, a magnetoresistive element having the magnetic film, and a magnetic memory including the magnetoresistive element. That is, by further inserting a Pt layer between the non-magnetic layer and the magnetic layer in the pinned layer, the antiferromagnetic coupling between the magnetic layers is maintained even when an annealing treatment is performed after forming the protective film, and the crystalline orientation and perpendicular magnetic anisotropy of the magnetic layer are also maintained, enabling strong pinning and maintaining the performance of the magnetoresistive element as a magnetic memory. [Brief explanation of the drawings]

[0035] [Figure 1] Figure 1(a) shows a schematic diagram of the top-pin structure of STT-MRAM, and Figure 1(b) shows a schematic diagram of the bottom-pin structure of STT-MRAM. [Figure 2] An outline of SOT-MRAM is shown. [Figure 3] Figure 3(a) shows the relationship between the magnitude of the drive current depending on the direction of the current during writing and the magnitude of the required reversal current depending on the direction of magnetization reversal in an MRAM with a top-pin structure, and Figure 3(b) shows the relationship between the magnitude of the drive current depending on the direction of the current during writing and the magnitude of the required reversal current depending on the direction of magnetization reversal in an MRAM with a top-pin structure. [Figure 4] Figure 4(a) shows the relationship between the magnitude of the drive current depending on the direction of the current during writing and the magnitude of the required reversal current depending on the direction of magnetization reversal in a bottom-pinned MRAM, and Figure 4(b) shows the relationship between the magnitude of the drive current depending on the direction of the current during writing and the magnitude of the required reversal current depending on the direction of magnetization reversal in a bottom-pinned MRAM. [Figure 5] 1 shows a longitudinal sectional view of an example of a magnetoresistive effect element of the present invention. [Figure 6] 1 shows a longitudinal sectional view of an example of a magnetoresistive effect element of the present invention. [Figure 7] 1 shows a longitudinal sectional view of an example of a magnetoresistive effect element of the present invention. [Figure 8] 1 shows a longitudinal sectional view of an example of a magnetoresistive effect element of the present invention. [Figure 9] The structure of the film used to evaluate the heat resistance of the magnetic film with the top pin structure is shown. [Figure 10] The results of heat resistance evaluation of the magnetic film with the top pin structure are shown. [Figure 11] 1 shows a layer structure used in evaluating the heat resistance of a magnetoresistive effect element having a top-pin structure as a comparative example. [Figure 12] 10 shows the results of evaluating the heat resistance of a magnetoresistive effect element having a top-pin structure as a comparative example. [Figure 13] 1 shows an X-ray diffraction spectrum of an antiferromagnetically coupled magnetic layer (Co) in a pinned layer of a top-pinned structure. [Figure 14] An example of an X-ray diffraction spectrum of Co with low crystal orientation is shown below. [Figure 15] 1 shows a longitudinal sectional view of an example of a magnetoresistive effect element of the present invention. [Figure 16] 1 shows a longitudinal sectional view of an example of a magnetoresistive effect element of the present invention. [Figure 17] 1 shows a longitudinal sectional view of an example of a magnetoresistive effect element of the present invention. [Figure 18] 1 shows a longitudinal sectional view of an example of a magnetoresistive effect element of the present invention. [Figure 19] 1 shows the layer structure used in evaluating the heat resistance of a magnetoresistive effect element with a bottom pin structure. [Figure 20] 1 shows the results of heat resistance evaluation of a magnetoresistive element with a bottom pin structure. [Figure 21] 1 shows a longitudinal sectional view of an example of a magnetoresistive effect element of the present invention. [Figure 22] 1 shows a longitudinal cross-sectional view of an example of a magnetic film of the present invention. [Figure 23] 1 shows a longitudinal cross-sectional view of an example of a magnetic film of the present invention. [Figure 24] 1 shows a longitudinal cross-sectional view of an example of a magnetic film of the present invention. [Figure 25] 1 shows a longitudinal cross-sectional view of an example of a magnetic film of the present invention. [Figure 26] 1 shows a longitudinal cross-sectional view of an example of a magnetic film of the present invention. [Figure 27] 1 shows a longitudinal cross-sectional view of an example of a magnetic film of the present invention. [Figure 28] 1 shows a longitudinal sectional view of an example of a magnetoresistive effect element of the present invention. [Figure 29]1 shows a longitudinal sectional view of an example of a magnetoresistive effect element of the present invention. [Figure 30] 1 shows a longitudinal sectional view of an example of a magnetoresistive effect element of the present invention. [Figure 31] 1 shows a longitudinal sectional view of an example of a magnetoresistive effect element of the present invention. [Figure 32] 1 shows a longitudinal sectional view of an example of a magnetoresistive effect element of the present invention. [Figure 33] An example of the magnetic memory of the present invention will be described. [Figure 34] 1 shows a conventional example of a magnetoresistive effect element with a top-pin structure. [Figure 35] 1 shows a conventional example of a magnetoresistive effect element with a bottom pin structure. [Figure 36] An example of the film configuration used to evaluate the heat resistance of the magnetic film of the present invention is shown in Figure 36(a). In Figure 36(a), a non-magnetic layer is disposed on the adjustment layer side, and a Pt layer is disposed on the non-magnetic layer. In Figure 36(b), a Pt layer is disposed on the adjustment layer side, and a non-magnetic layer is disposed on the Pt layer. [Figure 37] The heat resistance evaluation results of an example of the magnetic film of the present invention are shown in Figure 37(a) and Figure 37(b) which show the magnetization curves of the evaluation element of Figure 36(a). [Figure 38] The results of evaluating the heat resistance of an example of the magnetic film of the present invention are shown below. [Figure 39] 39(a) and 39(b) are longitudinal cross-sectional views of an example of a magnetoresistive effect element of the present invention, and FIG. 39(c) shows an example of a magnetic film of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0036] The magnetic film, magnetoresistive element, and magnetic memory of the present invention will be described in detail below with reference to the drawings. It should be noted that the drawings are merely examples, and that the present invention is not limited to these examples, although reference numerals are used for explanation.

[0037] (Embodiment 1) 5 shows the basic configuration of the first embodiment of the present invention. The basic configuration of the magnetoresistive effect element is a bottom electrode (E1), a recording layer (F1), a first barrier layer (B1), a first adjustment layer (A1), a first magnetic layer (21), a first non-magnetic layer (31), a first Pt layer (41), a second magnetic layer (22), and a cap layer (C1) arranged adjacent to each other in this order. The first adjustment layer (A1), the first magnetic layer (21), the first non-magnetic layer (31), the first Pt layer (41), and the second magnetic layer (22) form a first fixed layer (P1). Since the first fixed layer (P1) is disposed on the lower electrode (E1), the recording layer (F1), and the first barrier layer (B1), the configuration of the first embodiment is part or all of a magnetoresistive effect element with a top-pin structure.

[0038] The magnetization directions of the first magnetic layer (21) and the second magnetic layer (22) are both perpendicular to the film surface, and the first magnetic layer (21) and the second magnetic layer (22) are antiferromagnetically coupled to each other.

[0039] The first magnetic layer (21) and the second magnetic layer (22) contain any one of Co, Fe, and Ni. The first magnetic layer (21) and the second magnetic layer (22) may further contain a non-magnetic element such as W, Ta, Hf, Zr, Nb, Mo, Ti, V, Cr, Si, Al, B, Pd, or Pt. Specific examples include Co, Fe, Ni, CoFe, FeNi, CoNi, CoB, etc., but Co is more preferred because it sandwiches the first non-magnetic layer (31) and the first Pt layer (41) described below, creating antiferromagnetic coupling between the two magnetic layers, and making it easier for the magnetization directions of both magnetic layers to be perpendicular to the film surface. The thickness of each of the first magnetic layer (21) and the second magnetic layer (22) is preferably in the range of 0.3 nm to 3.0 nm, and more preferably in the range of 0.5 nm to 1.1 nm, because if the thickness is too thin, stable ferromagnetism cannot be obtained, while if the thickness is greater than 3 nm, the antiferromagnetic coupling becomes significantly weaker. The first magnetic layer (21) and the second magnetic layer (22) may be made up of multiple layers, such as a multilayer film of Co / Pt / Co or Co / Pt / Co / Pt / Co. The thickness of the second magnetic layer (22) is preferably thicker than the thickness of the first Pt layer (41) described later.

[0040] The crystal structure of the first magnetic layer (21) and the second magnetic layer (22) preferably has an fcc (111) structure (face-centered cubic lattice structure), because the higher the crystal orientation, the easier it is to maintain perpendicular magnetic anisotropy. Furthermore, when the primary element of the first magnetic layer (21) and / or the second magnetic layer (22) is Co, it is desirable that the X-ray diffraction spectrum have a primary peak of X-ray diffraction intensity between 42° and 43°, where 2θ is twice the angle of incidence of the X-rays. When a spectrum peak appears between 2θ of 42° and 43°, the lattice constant of Co is approximately the same as that of bulk Co(111). The inventors have found that when Co has little distortion in this way, the perpendicular magnetic anisotropy is strong.

[0041] The first non-magnetic layer (31) antiferromagnetically couples the magnetic layers with the elemental film that constitutes the non-magnetic layer, and the interlayer exchange coupling energy between the magnetic layers, i.e., the antiferromagnetic coupling force, is adjusted by the constituent elements and their film thickness. Examples of materials whose interlayer exchange coupling energy changes depending on the film thickness include Ir, Ru, Rh, and Os. The first non-magnetic layer (31) may also contain other elements, such as Ta, B, Nb, V, etc., that are used in alloys to the extent that the crystal structure is not changed.

[0042] When the first non-magnetic layer (31) contains Ir as a main element, it is desirable to adjust the thickness to 0.5±0.15 nm or 1.35±0.1 nm, at which the antiferromagnetic coupling force reaches its peak. When the first non-magnetic layer (31) contains Ru as the main element, it is desirable to adjust the thickness to 0.9±0.2 nm or 0.4±0.15 nm, at which the antiferromagnetic coupling force reaches its peak.

[0043] The first Pt layer (41) contains Pt as a main element and is inserted adjacent to and between the first non-magnetic layer (31) and the second magnetic layer (22). The thickness of the first Pt layer (41) is preferably in the range of 0.1 nm to 0.9 nm, more preferably in the range of 0.25 nm to 0.7 nm, and is preferably thinner than the thickness of the second magnetic layer (22).

[0044] The first adjusting layer (A1) of the first pinned layer (P1) preferably contains Pt and is a multilayer film formed by stacking multiple Co / Pt layers. As shown in FIG. 5, the Pt layers of the Co / Pt multilayer film of the first adjusting layer (A1) are arranged so as to be inserted between the Co layers. The layer adjacent to the first magnetic layer (21) may also be a Pt layer. The layer may also contain other elements to the extent that they do not change the crystal structure and / or properties of the layer. In the Co / Pt multilayer film of the first adjusting layer (A1), the Co film thickness is preferably in the range of 0.2 nm to 0.7 nm, more preferably in the range of 0.2 nm to 0.4 nm. The Pt film thickness is preferably in the range of 0.4 nm to 1.1 nm, more preferably in the range of 0.6 nm to 0.9 nm. In addition, in the Co / Pt multilayer film of the first adjusting layer (A1), the Pt film thickness is preferably thicker than the Co film thickness. Furthermore, the thickness of the Co layer of the first adjusting layer (A1) adjacent to the first barrier layer (B1) is preferably in the range of 0.3 nm to 1.6 nm, and more preferably in the range of 0.5 nm to 1.4 nm, regardless of the above-mentioned range.

[0045] The cap layer (C1) is provided on the opposite side of the first fixed layer (P1) from the first barrier layer (B1), and is a layer including an upper electrode, which electrically connects the first fixed layer (P1) of the magnetoresistive effect element to the bit line of the select transistor. In addition to the upper electrode, the cap layer (C1) may also include a non-magnetic layer or the like required to improve the characteristics of the magnetoresistive element, which may be appropriately formed between the upper electrode and the first fixed layer (P1).

[0046] The first barrier layer (B1) is disposed on the first adjusting layer (A1) side of the first fixed layer (P1), and is a tunnel barrier layer made of an insulating layer, forming a magnetic tunnel junction between the first fixed layer (P1) and the recording layer (F1) described below. Insulators such as MgO, Al2O3, SiO2, TiO, Hf2O, and ScC are used, and MgO and ScC are preferably used, so that the combination of materials for the two end faces will produce a large magnetoresistance change rate. The thickness of the first barrier layer (B1) is preferably 0.5 nm or more, more preferably 0.8 nm or more, in order to increase the TMR ratio. C In order to reverse the magnetization, the thickness is preferably 2.0 nm or less, and more preferably 1.2 nm or less. Therefore, it is adjusted to the range of 0.5 to 2.0 nm, more preferably 0.8 to 1.2 nm.

[0047] The recording layer (F1) is disposed adjacent to the first barrier layer (B1) on the opposite side to the first pinned layer (P1), and its magnetization direction is perpendicular to the film surface. The recording layer (F1) contains at least one of Co, Fe, and Ni. The recording layer (F1) may further contain a non-magnetic element such as W, Ta, Hf, Zr, Nb, Mo, Ti, V, Cr, Si, Al, B, Pd, or Pt. Specific examples include Co, Fe, Ni, CoFe, FeNi, CoNi, CoB, FeB, NiB, CoFeB, etc., with CoFeB and FeB being more preferred. The recording layer (F1) may also be a Co / Pt multilayer film. It is desirable that the recording layer (F1) has perpendicular magnetic anisotropy due to the interface magnetic anisotropy with the first barrier layer (B1). The recording layer (F1) may have one or more non-magnetic insertion layers such as W, Ta, Mo, etc. inserted therein, or may have layers such as MgO inserted therein to increase the number of interfaces and further enhance the perpendicular magnetic anisotropy.

[0048] The bottom electrode (E1) is disposed on the opposite side of the recording layer (F1) from the first barrier layer (B1). The bottom electrode (E1) is electrically connected to a selection transistor (not shown), and the magnetoresistive element receives a current from the selection transistor for writing and reading.

[0049] In the first embodiment, as shown in FIGS. 6 and 8, a first reference layer (R1) may be provided between the first barrier layer (B1) and the first adjusting layer (A1).

[0050] The first reference layer (R1) is inserted to improve the characteristics of the magnetoresistive element, particularly the TMR ratio. The first reference layer (R1) includes a magnetic layer and a non-magnetic layer, the magnetic layer being adjacent to the first barrier layer (B1), and the non-magnetic layer being adjacent to the first adjustment layer (A1). The magnetic layer contains at least one of Co, Ni, and Fe. Furthermore, the magnetic layer of the first reference layer (R1) may further contain a non-magnetic element such as W, Ta, Hf, Zr, Nb, Mo, Ti, V, Cr, Si, Al, B, Pd, or Pt. Specific examples include Co, Fe, Ni, CoFe, FeNi, CoNi, CoB, FeB, NiB, and CoFeB, with CoFeB and FeB being more preferred. The thickness of the magnetic layer of the first reference layer (R1) is preferably in the range of 0.3 nm to 3.0 nm, and more preferably in the range of 1.0 nm to 1.4 nm. The non-magnetic layer of the first reference layer (R1) is inserted between the magnetic layer of the first reference layer (R1) and the first adjustment layer (A1) for the purpose of, for example, increasing the crystalline orientation of the magnetic layer of the first adjustment layer (A1). The non-magnetic layer of the first reference layer (R1) is exemplified by Ta, W, Mo, etc., and has a film thickness of about 0.3 nm. The magnetic layer of the first reference layer (R1) and the magnetic layer of the first adjustment layer (A1) adjacent to the first reference layer (R1) are magnetically coupled.

[0051] In addition, in the first embodiment, one or more sets of a non-magnetic layer / Pt layer / magnetic layer may be disposed adjacent to the second magnetic layer (22) on the side opposite to the first Pt layer (41), as shown in Figures 7 and 8. The second magnetic layer (22) and the third magnetic layer (23) of the first pinned layer (P1) are antiferromagnetically coupled to each other, and the third magnetic layer (23) and the fourth magnetic layer (24) are antiferromagnetically coupled to each other.

[0052] The features of the first embodiment will be described. First, as mentioned in the background art, in order to generate antiferromagnetic coupling between magnetic layers, a magnetic layer and a nonmagnetic layer are usually disposed adjacent to each other (see FIG. 34 for a conventional example). However, with the conventional layer structure, it is difficult to maintain perpendicular magnetic anisotropy and antiferromagnetic coupling, especially after annealing at 300°C to 400°C. In the present invention, by inserting a Pt layer between the magnetic layer and the non-magnetic layer between the magnetic layers that form antiferromagnetic coupling, the crystalline orientation of the magnetic layer is improved, and the perpendicular magnetic anisotropy and antiferromagnetic coupling are maintained even after annealing at 300°C to 400°C (the same applies to other embodiments).

[0053] Furthermore, in order to achieve sufficient pinning with conventional layer structures, the magnetic layers that form antiferromagnetic coupling required a multilayer film with an increased number of layers, such as Co / Pt / Co / Pt / Co, as shown in Figure 11. However, in the present invention, the first and second magnetic layers that form antiferromagnetic coupling can maintain perpendicular magnetic anisotropy and antiferromagnetic coupling even with a single magnetic layer, such as a Co layer, and the number of layers of magnetic layers can be significantly reduced (the same applies to other embodiments). As will be described later, even in the conventional example of FIG. 11, it is difficult to obtain perpendicular magnetic anisotropy or antiferromagnetic coupling by annealing at 400°C.

[0054] The evaluation results of the first embodiment are described below.

[0055] -Evaluation Test 1- The perpendicular magnetic anisotropy of the magnetoresistive element of the first embodiment was evaluated. The layer structure used for the evaluation is shown in Figure 9. The structure is bottom electrode / CoFeB / MgO / CoFeB(1) / W(0.3) / Co(0.25) / Pt(0.7) / Co(0.25) / Pt(0.7) / Co(0.25) / Pt(0.7) / Co(0.9) / Ir(0.53) / Pt(0.6) / Co(0.9) / Ir(0.53) / Pt(0.6) / Co(0.9) / Ir(0.53) / Ta(5), and the thickness (nm) is shown in parentheses. In the pinned layer of the evaluation element, Pt layers (41, 42, 43) were inserted between magnetic layers (22, 23, 24) disposed on non-magnetic layers (31, 32, 33), respectively. The evaluation element shown in FIG. 9 was fabricated and annealed at 300° C., 350° C., and 400° C. for 1 hour. The magnetization curves obtained for each evaluation film are shown in Figures 10(a) to 10(c). The magnetization curves, with the product of magnetization and film thickness Mt on the vertical axis and the product of vacuum permeability and magnetic field μH on the horizontal axis, were obtained by sweeping the magnetic field perpendicular to the film surface. When perpendicular magnetic anisotropy is present, a nearly perpendicular loop is obtained when μH is near zero. Furthermore, when there is antiferromagnetic coupling between the nonmagnetic layer and the magnetic layers sandwiching the Pt layer, the product of magnetization and film thickness Mt becomes even smaller near zero magnetic field, and a nearly perpendicular loop is obtained near zero. Although not shown here, when a magnetic field was applied in-plane, the MH loop did not show a nearly vertical loop in zero magnetic field, but instead showed a curve like that shown in FIG. 12(c).

[0056] In Figures 10(a) to 10(c), whether the annealing temperature is 300°C, 350°C, or 400°C, the product Mt of magnetization and film thickness becomes small near zero magnetic field, and a nearly perpendicular loop is shown near zero, confirming that the magnetic layer exhibits perpendicular magnetic anisotropy and antiferromagnetic coupling.

[0057] -Evaluation Test 2- The perpendicular magnetic anisotropy of a magnetoresistive element having a layer structure serving as a comparative example to the first embodiment was evaluated. FIG. 11 shows the layer structure used in the evaluation of the comparative example. The composition of the bottom electrode is CoFeB / MgO / CoFeB (1) / W (0.3) / Co (0.25) / Pt (0.7) / Co (0.25) / Pt (0.7) / Co (0.25) / Pt (0.7) / Co (0.5) / Pt (0.25) / Co (0.5) / Pt (0.25) / Co (0.5) / Ir (0.53) / Co (0.5) / Pt (0.25) / Co (0.5) / Pt (0.25) / Co (0.5) / Ir (0.53) / Co (0.5) / Pt (0.25) / Co (0.5) / Pt (0.25) / Co (0.5) / Ir (0.53) / Ta (5), and the thickness (nm) is shown in parentheses. The evaluation element of the comparative example has a magnetic layer (Co layer in the evaluation element) adjacent to a non-magnetic layer (Ir in the evaluation element) directly on top of it, and has a non-magnetic layer / magnetic layer configuration, rather than the non-magnetic layer / Pt layer / magnetic layer configuration of embodiment 1. The evaluation element shown in FIG. 11 was fabricated and annealed at 300° C., 350° C., and 400° C. for 1 hour. The magnetization curves obtained for each evaluation film are shown in FIG. 12(a) to FIG. 12(c).

[0058] Figures 12(a) and 12(b) show that when the annealing temperature was 300°C and 350°C, the magnetic layer exhibited perpendicular magnetic anisotropy, and antiferromagnetic coupling between the magnetic layers of the pinned layer was also confirmed. However, Figure 12(c) shows that a nearly perpendicular loop was not obtained at zero magnetic field, so perpendicular magnetic anisotropy could not be confirmed at 400°C. Although not shown here, when an external magnetic field was applied in-plane at 400°C, a nearly perpendicular loop was obtained at zero magnetic field, indicating that the film had become an in-plane magnetized film. Furthermore, antiferromagnetic coupling between the magnetic layers of the pinned layer could not be confirmed. That is, in the configuration of Figure 11, in which, unlike in embodiment 1, a Pt layer is not inserted between the antiferromagnetically coupled magnetic layers and a magnetic layer is adjacent to both sides of the non-magnetic layer, it was found that the perpendicular magnetic anisotropy is not maintained by annealing at 400°C, and there is no antiferromagnetic coupling between the magnetic layers of the pinned layer. Furthermore, as in this comparative example, it is usually necessary to fabricate a Co / Pt multilayer structure to fabricate a perpendicular magnetization film. When fabricating such a multilayer structure, the manufacturing equipment must prepare cathodes for the number of Co and Pt layers to ensure throughput. Therefore, the more layers there are, the higher the manufacturing costs become. On the other hand, the present invention is advantageous in terms of manufacturing costs because it can form strong antiferromagnetic coupling in perpendicular films even with a small number of layers.

[0059] -Evaluation Test 3- The crystal orientation of the magnetoresistive element of the first embodiment was evaluated. The evaluation element shown in FIG. 9 was fabricated and subjected to annealing at 400° C. for 1 hour. The X-ray diffraction spectrum obtained for the evaluation element is shown in Figure 13. The X-ray diffraction spectrum shows the X-ray diffraction intensity (arbitrary scale) for twice the angle of incidence (2θ) of the X-rays onto the sample (θ), and the angle 2θ at which a diffraction peak appears depends on the crystal structure.

[0060] Figure 13 shows that there is a main peak at 2θ of 42.3°, indicating a predominant fcc (111) structure. Focusing on the second magnetic layer, it can be seen that the crystalline orientation of the second magnetic layer (22) can be enhanced by the first Pt layer (41) inserted adjacent to and below the second magnetic layer (22). Furthermore, the diffraction peaks reveal that the lattice constant of Co is nearly identical to that of bulk Co (111). Thus, it can be seen that perpendicular magnetic anisotropy is enhanced when there is little strain in the Co. Although not shown, when the results were analyzed together with the results of evaluation elements having other configurations, it was found that the crystalline orientation of the second magnetic layer (22) can be further improved when the film thickness of the second magnetic layer (22) is thicker than the film thickness of the first Pt layer (41), and since the main X-ray diffraction peak is at an X-ray incident angle 2θ of 42° or more and 43° or less, the crystalline structure of Co is mainly an fcc(111) structure. In this way, it was found that the element having the configuration of the first embodiment can improve the crystal orientation of the magnetic layer, and therefore, it is easy to maintain perpendicular magnetic anisotropy and become a perpendicular magnetization film.

[0061] -Evaluation Test 4- As a comparative example for the first embodiment, the X-ray diffraction spectrum was confirmed in the case of a layer structure with low crystal orientation. FIG. 14 shows an example of an X-ray diffraction spectrum of a magnetoresistive element in which the axis of easy magnetization of the magnetic layer is in the in-plane direction.

[0062] 14, there is a main peak at 2θ of 40.6°, and it can be seen that the fcc(111) Co lattice is distorted by the Pt, and the Co lattice constant is elongated in the direction perpendicular to the film surface. The inventors have found that when such distortion occurs, the magnetization direction of Co is unlikely to become perpendicular. In other words, unlike the element in Evaluation Test 3 in which the magnetization direction is perpendicular to the film surface, when the easy axis of magnetization of the magnetic layer is in the in-plane direction, there is no major X-ray diffraction peak at an X-ray incident angle 2θ of 42° or more and 43° or less, and it was revealed that the magnetization direction of Co is unlikely to be perpendicular.

[0063] (Embodiment 2) 15 shows the basic configuration of the second embodiment of the present invention. The basic configuration of the magnetoresistive effect element is a lower electrode (E1), a first adjustment layer (A1), a first magnetic layer (21), a first non-magnetic layer (31), a first Pt layer (41), a second magnetic layer (22), a second barrier layer (B2), a recording layer (F1), and a cap layer (C1) arranged in this order. The first adjustment layer (A1), the first magnetic layer (21), the first non-magnetic layer (31), the first Pt layer (41), and the second magnetic layer (22) form a second fixed layer (P2). Since a second fixed layer (P2), a second barrier layer (B2), and a recording layer (F1) are arranged in this order on the lower electrode (E1), the configuration of embodiment 2 is part or all of a magnetoresistive effect element with a bottom pin structure.

[0064] The magnetization directions of the first magnetic layer (21) and the second magnetic layer (22) are both perpendicular to the film surface, and the first magnetic layer (21) and the second magnetic layer (22) are antiferromagnetically coupled to each other.

[0065] The first adjusting layer (A1) included in the bottom pin structure preferably contains Pt and is a Pt layer. In this case, the film thickness of the first adjusting layer (A1) is preferably 3 nm or more, more preferably 5 nm or more. This first adjusting layer (A1) may also be called an underlayer.

[0066] The first non-magnetic layer (31) of the second pinned layer (P2) antiferromagnetically couples the magnetic layers with the elemental film that constitutes the non-magnetic layer, and the interlayer exchange coupling energy between the magnetic layers, i.e., the antiferromagnetic coupling force, is adjusted by the constituent elements and their film thickness. Examples of materials whose interlayer exchange coupling energy changes depending on the film thickness include Ir, Ru, Rh, and Os. The first non-magnetic layer (31) may also contain other elements, such as Ta, B, Nb, V, etc., that are used in alloys to the extent that the crystal structure is not changed. When the first non-magnetic layer (31) contains Ir as a main element, it is desirable to adjust the thickness to 0.5±0.15 nm or 1.35±0.1 nm, at which the antiferromagnetic coupling force reaches its peak. When the first non-magnetic layer (31) contains Ru as the main element, it is desirable to adjust the thickness to 0.9±0.2 nm or 0.4±0.15 nm, at which the antiferromagnetic coupling force reaches its peak.

[0067] The details of the first magnetic layer (21), the first Pt layer (41), and the second magnetic layer (22) of the second pinned layer (P2) are the same as those in the first embodiment.

[0068] The second barrier layer (B2) is a tunnel barrier layer made of an insulating layer and is disposed on the opposite side of the second fixed layer (P2) from the first adjustment layer (A1), and forms a magnetic tunnel junction together with the second fixed layer (P2) and the first recording layer (F1) described below. Insulators such as MgO, Al2O3, SiO2, TiO, Hf2O, and ScC are used, with MgO and ScC being preferred, so that the combination of materials for the two end faces will produce a large magnetoresistance change rate. The thickness of the second barrier layer (B2) is preferably 0.5 nm or more, more preferably 0.8 nm or more, in order to increase the TMR ratio. C In order to reverse the magnetization, the thickness is preferably 2.0 nm or less, and more preferably 1.2 nm or less. Therefore, it is adjusted to the range of 0.5 nm to 2.0 nm, and more preferably to the range of 0.8 nm to 1.2 nm.

[0069] The recording layer (F1) is disposed adjacent to the second barrier layer (B2) on the opposite side to the second fixed layer (P2), and its magnetization direction is perpendicular to the film surface. The recording layer (F1) contains at least one of Co, Fe, and Ni. The recording layer (F1) may further contain a non-magnetic element such as W, Ta, Hf, Zr, Nb, Mo, Ti, V, Cr, Si, Al, B, Pd, or Pt. Specific examples include Co, Fe, Ni, CoFe, FeNi, CoNi, CoB, FeB, NiB, CoFeB, etc., with CoFeB and FeB being more preferred. The recording layer (F1) may also be a Co / Pt multilayer film. It is desirable that the recording layer (F1) has perpendicular magnetic anisotropy due to the interface magnetic anisotropy with the second barrier layer (B2). The first recording layer (F1) may have one or more non-magnetic insertion layers such as W, Ta, Mo, etc. inserted therein, or may have layers such as MgO inserted therein to increase the number of interfaces and further enhance the perpendicular magnetic anisotropy.

[0070] The cap layer (C1) is provided on the opposite side of the second fixed layer (P2) from the second barrier layer (B2), and is a layer including an upper electrode, which electrically connects the second fixed layer (P2) of the magnetoresistive effect element to the bit line of the select transistor. In addition to the upper electrode, the cap layer (C1) may also include a non-magnetic layer or the like required to improve the characteristics of the magnetoresistive element, which may be appropriately formed between the upper electrode and the second fixed layer (P2).

[0071] The bottom electrode (E1) is disposed on the opposite side of the second fixed layer (P2) from the second barrier layer (B2). The bottom electrode (E1) is electrically connected to a selection transistor (not shown), and the magnetoresistive element receives a current from the selection transistor for writing and reading.

[0072] In the second embodiment, a first reference layer (R1) may be provided on the opposite side of the second barrier layer (B2) to the recording layer (F1), as shown in Figures 16 and 18. The details of the first reference layer (R1) are the same as those in the first embodiment.

[0073] In the second embodiment, one or more sets of a non-magnetic layer / Pt layer / magnetic layer may be disposed adjacent to the second magnetic layer (22) on the side opposite to the first Pt layer (41), as shown in Figures 17 and 18. The first magnetic layer (21) and the second magnetic layer (22) and the second magnetic layer (22) and the third magnetic layer (23) are antiferromagnetically coupled to each other.

[0074] The features of the second embodiment will be described. In the second embodiment, too, by inserting a Pt layer between the magnetic layers that form antiferromagnetic coupling and below the magnetic layers, the crystalline orientation of the magnetic layers is improved, and the perpendicular magnetic anisotropy and antiferromagnetic coupling are maintained even after annealing at 300°C to 400°C. The evaluation results of the second embodiment are described below.

[0075] -Evaluation Test 5- The perpendicular magnetic anisotropy of the magnetoresistive element of the second embodiment was evaluated. Figure 19 shows the layer structure used for the evaluation. Ta(5) / Pt(3) / Co(0.9) / Ir(t Ir ) / Pt(0.6) / Co(0.9) / Ir(t Ir ) / Pt(0.6) / Co(0.9) / Ir(t Ir ) / Ta(5), and the thickness (nm) is shown in parentheses. Ir can effectively antiferromagnetically couple the upper and lower magnetic layers with a film thickness of 0.53 nm. IrEvaluation films of 0.5 nm and 0.55 nm were prepared and annealed at 300°C and 400°C for 1 hour.

[0076] 20(a) to 20(d) show the MH curves (magnetization curves) when an external magnetic field is applied perpendicular to the film surface. From these, it was confirmed that the magnetic layer exhibited perpendicular magnetic anisotropy and that antiferromagnetic coupling existed between the Co layers in the magnetic layer, regardless of whether the Ir film thickness was 0.5 nm or 0.55 nm or the annealing temperature was 300°C or 400°C.

[0077] (Embodiment 3) FIG. 21 shows the basic configuration of the third embodiment of the present invention. The basic configuration of the magnetoresistive effect element is such that the lower electrode (E1) / first adjustment layer (A1) / first magnetic layer (21) / first non-magnetic layer (31) / first Pt layer (41) / second magnetic layer (22) / second non-magnetic layer (32) / second Pt layer (42) / third magnetic layer (23) / second barrier layer (B2) / recording layer (F1) / first barrier layer (B1) / first reference layer (R1) / first adjustment layer (A1) / first magnetic layer (21) / first non-magnetic layer (31) / first Pt layer (41) / second magnetic layer (22) / second non-magnetic layer (32) / second Pt layer (42) / third magnetic layer (23) / cap layer (C1) are arranged adjacent to each other in this order. The first reference layer (R1), first adjustment layer (A1), first magnetic layer (21), first non-magnetic layer (31), first Pt layer (41), second magnetic layer (22), second non-magnetic layer (32), second Pt layer (42), and third magnetic layer (23) above the recording layer (F1) form a first fixed layer (P1). The first adjustment layer (A1), first magnetic layer (21), first non-magnetic layer (31), first Pt layer (41), second magnetic layer (22), second non-magnetic layer (32), second Pt layer (42), and third magnetic layer (23) below the recording layer (F1) form a second fixed layer (P2). That is, two fixed layers are arranged between the first barrier layer (B1), the recording layer (F1) and the second barrier layer (B2): a first fixed layer (P1) on the first barrier layer (B1) side and a second fixed layer (P2) on the second barrier layer (B2) side.

[0078] Although the third embodiment shows two pinned layers each having an antiferromagnetically coupled structure in which a nonmagnetic layer / Pt layer / magnetic layer is repeated twice, a configuration in which one, three, four, five or more such nonmagnetic layers are inserted may also be employed. Furthermore, the number of nonmagnetic layers may differ between the first pinned layer (P1) and the second pinned layer (P2), or only one of the first pinned layer (P1) and the second pinned layer (P2) may have a nonmagnetic layer / Pt layer / magnetic layer structure.

[0079] (Fourth embodiment) The fourth embodiment has a magnetic film configuration that is included in the first and second embodiments. As shown in Fig. 22, a first magnetic layer (21), a first non-magnetic layer (31), a first Pt layer (41), and a second magnetic layer (22) are arranged adjacent to each other in this order. The magnetization directions of the first magnetic layer (21) and the second magnetic layer (22) are both perpendicular to the film surface, and the first magnetic layer (21) and the second magnetic layer (22) are antiferromagnetically coupled to each other.

[0080] The first non-magnetic layer (31) antiferromagnetically couples the magnetic layers with the elemental film that constitutes the non-magnetic layer, and the interlayer exchange coupling energy between the magnetic layers, i.e., the antiferromagnetic coupling force, is adjusted by the constituent elements and their film thickness. Examples of materials whose interlayer exchange coupling energy changes depending on the film thickness include Ir, Ru, Rh, and Os. The first non-magnetic layer (31) may also contain other elements, such as Ta, B, Nb, V, etc., that are used in alloys to the extent that the crystal structure is not changed. When the first non-magnetic layer (31) contains Ir as a main element, it is desirable to adjust the thickness to 0.5±0.15 nm or 1.35±0.1 nm, at which the antiferromagnetic coupling force reaches its peak. When the first non-magnetic layer (31) contains Ru as the main element, it is desirable to adjust the thickness to 0.9±0.2 nm or 0.4±0.15 nm, at which the antiferromagnetic coupling force reaches its peak.

[0081] The details of the first magnetic layer (21), the first Pt layer (41), and the second magnetic layer (22) are the same as those in the first embodiment.

[0082] In addition, in the fourth embodiment, one or more sets of a non-magnetic layer / Pt layer / magnetic layer may be disposed adjacent to the second magnetic layer (22) on the side opposite to the first Pt layer (41), as shown in Figures 23 and 24. The magnetic layers are antiferromagnetically coupled to each other.

[0083] As described above, the fourth embodiment has the features of the invention shown in the first and second embodiments, and the layer structure of the first magnetic layer (21), first non-magnetic layer (31), first Pt layer (41), and second magnetic layer (22) enhances the crystalline orientation of the second magnetic layer (22), and can maintain the perpendicular magnetic anisotropy and antiferromagnetic coupling between the first magnetic layer (21) and the second magnetic layer (22) even after annealing at 400°C.

[0084] (Embodiment 5) The fifth embodiment has a magnetic layer configuration included in the first and second embodiments, and further includes a first adjustment layer (A1) in addition to the fourth embodiment. As shown in Fig. 25, the first adjustment layer (A1), the first magnetic layer (21), the first non-magnetic layer (31), the first Pt layer (41), and the second magnetic layer (22) are arranged adjacent to each other in this order.

[0085] The magnetization directions of the first magnetic layer (21) and the second magnetic layer (22) are both perpendicular to the film surface, and the first magnetic layer (21) and the second magnetic layer (22) are antiferromagnetically coupled to each other.

[0086] The first non-magnetic layer (31) antiferromagnetically couples the magnetic layers with the elemental film that constitutes the non-magnetic layer, and the interlayer exchange coupling energy between the magnetic layers, i.e., the antiferromagnetic coupling force, is adjusted by the constituent elements and their film thickness. Examples of materials whose interlayer exchange coupling energy changes depending on the film thickness include Ir, Ru, Rh, and Os. The first non-magnetic layer (31) may also contain other elements, such as Ta, B, Nb, V, etc., that are used in alloys to the extent that the crystal structure is not changed. When the first non-magnetic layer (31) contains Ir as a main element, it is desirable to adjust the thickness to 0.5±0.15 nm or 1.35±0.1 nm, at which the antiferromagnetic coupling force reaches its peak. When the first non-magnetic layer (31) contains Ru as the main element, it is desirable to adjust the thickness to 0.9±0.2 nm or 0.4±0.15 nm, at which the antiferromagnetic coupling force reaches its peak.

[0087] The details of the first magnetic layer (21), the first Pt layer (41), and the second magnetic layer (22) are the same as those in the first embodiment.

[0088] The first adjusting layer (A1) contains Pt, and examples thereof include a Pt layer containing Pt as the main element, and a Co / Pt multilayer film. It may also contain other elements to the extent that they do not change the crystal structure and / or properties of the layer.

[0089] In the fifth embodiment, one or more sets of a non-magnetic layer / Pt layer / magnetic layer may be disposed adjacent to the second magnetic layer (22) on the side opposite to the first Pt layer (41), as shown in Figures 26 and 27. The magnetic layers are antiferromagnetically coupled to each other.

[0090] In embodiment 5, a first adjustment layer (A1) is further provided in addition to embodiment 4, and therefore in addition to the effects shown in embodiment 4, the crystalline orientation of the magnetic layer of the fixed layer (especially the first magnetic layer) can be further enhanced, thereby improving the magnetic properties.

[0091] More specific examples will be described in the following embodiments 6 to 10.

[0092] (Sixth embodiment) 28 shows a more specific configuration of the top pin structure of the sixth embodiment of the present invention. The configuration of the magnetoresistive element is heavy metal layer (H1) / Co(0.5-1.4) / MgO(0.8-1.2) / Co(0.5-1.4) / Pt(0.6-0.9) / Co(0.2-0.4) / Pt(0.6-0.9) / Co(0.2-0.4) / Pt(0.6-0.9) / Co(0.5-1.1)(21) / Ir(0.4-0.6)(31) / Pt(0.25-0.6)(41) / Co(0.5-1.1)(22) / Ir(0.4-0.6)(32) / Pt(0.25-0.6)(42) / Co(0.5-1.1)(23) / Ir(0.4-0.6)(33) / Pt(0.25-0.6)(43) / Co(0.5-1.1)(24) The numerical range in parentheses indicates the range of film thickness (nm). Here, 21, 22, 23, and 24 correspond to the first magnetic layer, second magnetic layer, third magnetic layer, and fourth magnetic layer, respectively. 31, 32, and 33 correspond to the first non-magnetic layer, second non-magnetic layer, and third non-magnetic layer, respectively. 41, 42, and 43 correspond to the first Pt layer, second Pt layer, and third Pt layer, respectively.

[0093] In the layer structure of Embodiment 6, the maintenance of the crystalline orientation and perpendicular magnetic anisotropy of the magnetic layer of the pinned layer can be evaluated by the evaluation test described above. That is, the crystalline orientation can be confirmed by the presence of a main peak of the X-ray diffraction intensity in the X-ray diffraction spectrum, where the angle 2θ, which is twice the angle of incidence of the X-rays, is between 42° and 43°, and the state of perpendicular magnetic anisotropy and antiferromagnetic coupling can be confirmed by the presence of a substantially perpendicular loop in the magnetization curve of the evaluation film where μ0H is near zero. In examining the layer structure, the inventors discovered that in order to maintain crystal orientation, the X-ray diffraction spectrum has a peak between 42° and 43° by focusing on the ratio of Co to Pt, for example. Furthermore, in the layer configuration of the sixth embodiment, some or all of the antiferromagnetically coupled magnetic layers (first magnetic layer, second magnetic layer, third magnetic layer, and fourth magnetic layer) can be multi-layered, and the thickness of each layer, including the Pt layer inserted under the magnetic layers, can be thinned. As in the following example, the first Pt layer, second Pt layer, and third Pt layer (Pt(0.25-0.6)) in FIG. 28 can be Pt(0.2-0.4), and the second magnetic layer, third magnetic layer, and fourth magnetic layer (Co(0.5-1.1)) can be Co(0.4-0.6) / Pt(0.2-0.4) / Co(0.4-0.6), etc. Co(0.5-1.4) / MgO(0.8-1.2) / Co(0.5-1.4) / Pt(0.6-0.9) / Co(0.2-0.4) / Pt(0.6-0.9) / Co(0.2-0.4) / Pt(0.6-0.9) / Co(0.5-1.1) / Ir(0.4-0.6) / Pt(0.2-0.4) / Co(0.4-0.6) / Pt(0.2-0.4) / Co(0.4-0.6) / Ir(0.4-0.6) / Pt(0.2-0.4) / Co(0.4-0.6) / Pt(0.2-0.4) / Co(0.4-0.6) / Ir(0.4-0.6) / Pt(0.2-0.4) / Co(0.4-0.6) / Pt(0.2-0.4) / Co(0.4-0.6)

[0094] (Embodiment 7) 29 shows a more specific configuration of the seventh embodiment of the top pin structure of the present invention. The configuration of the magnetoresistive effect element is heavy metal layer (H1) / CoFeB (1.0-1.4) / MgO (0.8-1.2) / CoFeB (1.0-1.4) / Ta or W or Mo (0.3) / Co (0.2-0.4) / Pt (0.6-0.9) / Co (0.2-0.4) / Pt (0.6-0.9) / Co (0.2-0.4) / Pt (0.6-0.9) / Co (0.5-1.1) (21) / Ir (0.53) (31) / Pt(0.25-0.6)(41) / Co(0.5-1.1)(22) / Ir(0.4-0.6)(32) / Pt(0.25-0.6)(42) / Co(0.5-1.1)(23) / Ir(0.4-0.6)(33) / Pt(0.25-0.6)(43) / Co(0.5-1.1)(24) / A cap layer (C1) are arranged in this order. The range of values in parentheses indicates the range of film thickness (nm). Here, 21, 22, 23, and 24 correspond to the first magnetic layer, second magnetic layer, third magnetic layer, and fourth magnetic layer, respectively. 31, 32, and 33 correspond to the first non-magnetic layer, second non-magnetic layer, and third non-magnetic layer, respectively. 41, 42, and 43 correspond to the first Pt layer, second Pt layer, and third Pt layer, respectively. In the configuration of the seventh embodiment, a first reference layer (R1) is disposed on the first barrier layer (B1) side of the first fixed layer (P1).

[0095] As in the sixth embodiment, some or all of the antiferromagnetically coupled magnetic layers (first magnetic layer, second magnetic layer, third magnetic layer, and fourth magnetic layer) of the seventh embodiment may be multi-layered, and the thickness of each layer, including the Pt layer inserted under the magnetic layers, may be thin. As in the following example, the first Pt layer, second Pt layer, and third Pt layer (Pt(0.25-0.6)) in FIG. 29 may be Pt(0.2-0.4), and the second magnetic layer, third magnetic layer, and fourth magnetic layer (Co(0.5-1.1)) may be Co(0.4-0.6) / Pt(0.2-0.4) / Co(0.4-0.6), etc. CoFeB(1.0-1.4) / MgO(0.8-1.2) / CoFeB(1.0-1.4) / Ta or W or Mo(0.3) / Co(0.2-0.4) / Pt(0. 6-0.9) / Co(0.2-0.4) / Pt(0.6-0.9) / Co(0.2-0.4) / Pt(0.6-0.9) / Co(0.5-1.1) / Ir(0.53) / Pt(0.2-0.4) / Co(0.4-0.6) / Pt(0.2-0.4) / Co(0.4-0.6) / Ir(0.4-0.6) / Pt(0.2-0.4) / Co(0.4-0.6) / Pt(0.2-0.4) / Co(0.4-0.6) / Ir(0.4-0.6) / Pt(0.2-0.4) / Co(0.4-0.6) / Pt(0.2-0.4) / Co(0.4-0.6)

[0096] (Embodiment 8) 30 shows a more specific configuration of the bottom pin structure according to the eighth embodiment of the present invention. The magnetoresistive element has a configuration of Pt(>3) / Co(0.5-1.1)(21) / Ir(0.4-0.6)(31) / Pt(0.25-0.6)(41) / Co(0.5-1.1)(22) / Ir(0.4-0.6)(32) / Pt(0.25-0.6)(42) / Co(0.5-1.1)(23) / Ta or W or Mo (0.3) / CoFeB (1.0-1.4) / MgO (0.8-1.2) / CoFeB (1.0-1.4) / Ta or W or Mo (0.3) / CoFeB (1.0-1.4) / MgO (0.8-1.2) are arranged in this order. The numerical range in parentheses indicates the range of film thickness (nm). Here, 21, 22, and 23 correspond to the first magnetic layer, second magnetic layer, and third magnetic layer, respectively. 31 and 32 correspond to the first non-magnetic layer and second non-magnetic layer, respectively. 41 and 42 correspond to the first Pt layer and second Pt layer, respectively. In addition to having a non-magnetic layer / Pt layer / magnetic layer configuration, embodiment 8 is characterized in that a first reference layer (R1) is arranged on the second barrier layer (B2) side of the second fixed layer (P2), and the second barrier layer (B2) is MgO.

[0097] As in the sixth embodiment, in the layer configuration of the eighth embodiment, some or all of the antiferromagnetically coupled magnetic layers (first magnetic layer, second magnetic layer, third magnetic layer) can be multi-layered, and the thickness of each layer, including the Pt layer inserted under the magnetic layers, can be thinned. As in the following example, the first Pt layer and second Pt layer (Pt(0.25-0.6)) in FIG. 30 can be Pt(0.2-0.4), and the second magnetic layer and third magnetic layer (Co(0.5-1.1)) can be Co(0.4-0.6), etc. Pt(>3) / Co(0.4-0.6) / Ir(0.4-0.6) / Pt(0.2-0.4) / Co(0.4-0.6) / Ir(0.4-0.6) / Pt(0.2-0.4) / Co(0.4-0.6) / Ta or W or Mo (0.3) / CoFeB (1.0-1.4) / MgO (0.8-1.2) / CoFeB (1.0-1.4) / Ta or W or Mo (0.3) / CoFeB (1.0-1.4) / MgO (0.8-1.2) Furthermore, as shown below, the first Pt layer and second Pt layer (Pt(0.25-0.6)) in Figure 30 can be Pt(0.1-0.2), and the second magnetic layer and third magnetic layer (Co(0.5-1.1)) can be Co(0.2-0.3) / Pt(0.1-0.2) / Co(0.2-0.3), etc. Pt(>3) / Co(0.4-0.6) / Ir(0.4-0.6) / Pt(0.1-0.2) / Co(0.2-0.3) / Pt(0.1-0.2) / Co(0.2-0.3) / Ir(0.4-0.6) / Pt(0.1-0.2) / Co(0.2-0.3) / Pt(0.1-0.2) / Co(0.2-0.3) / Ta or W or Mo (0.3) / CoFeB (1.0-1.4) / MgO (0.8-1.2) / CoFeB (1.0-1.4) / Ta or W or Mo (0.3) / CoFeB (1.0-1.4) / MgO (0.8-1.2)

[0098] (Embodiment 9) 31 shows a more specific configuration of the bottom pin structure according to the ninth embodiment of the present invention. The configuration of the magnetoresistive element is Pt(>3) / Co(0.5-1.1)(21) / Ir(0.4-0.6)(31) / Pt(0.25-0.6)(41) / Co(0.5-1.1)(22) / Ir(0.4-0.6)(32) / Pt(0.25-0.6)(42) / Co(0.5-1.1)(23) / MgO(0.8-1.2) / Co(0.7-1.1) / Pt(0.5-0.8) / Co(0.7-1.1) / Pt(0.5-0.8) are arranged in this order. The numerical range in parentheses indicates the range of film thickness (nm). Here, 21, 22, and 23 correspond to the first magnetic layer, second magnetic layer, and third magnetic layer, respectively. 31 and 32 correspond to the first non-magnetic layer and second non-magnetic layer, respectively. 41 and 42 correspond to the first Pt layer and second Pt layer, respectively.

[0099] As in the sixth embodiment, in the layer configuration of the ninth embodiment, some or all of the antiferromagnetically coupled magnetic layers (first magnetic layer, second magnetic layer, third magnetic layer) can be multi-layered, and the thickness of each layer, including the Pt layer inserted under the magnetic layers, can be thinned. As in the following example, the first Pt layer and second Pt layer (Pt(0.25-0.6)) in FIG. 30 can be Pt(0.2-0.4), and the second magnetic layer and third magnetic layer (Co(0.5-1.1)) can be Co(0.4-0.6), etc. Pt(>3) / Co(0.4-0.6) / Ir(0.4-0.6) / Pt(0.2-0.4) / Co(0.4-0.6) / Ir(0.4-0.6) / Pt(0.2-0.4) / Co(0.4-0.6) / MgO(0.8-1.2) / Co(0.7-1.1) / Pt(0.5-0.8) / Co(0.7-1.1) / Pt(0.5-0.8) Furthermore, as shown below, the first Pt layer and second Pt layer (Pt(0.25-0.6)) in Figure 31 can be Pt(0.1-0.2), and the second magnetic layer and third magnetic layer (Co(0.5-1.1)) can be Co(0.2-0.3) / Pt(0.1-0.2) / Co(0.2-0.3), etc. Pt(>3) / Co(0.4-0.6) / Ir(0.4-0.6) / Pt(0.1-0.2) / Co(0.2-0.3) / Pt(0.1-0.2) / Co(0.2-0.3) / Ir(0.4-0.6) / Pt(0.1-0.2) / Co(0.2-0.3) / Pt(0.1-0.2) / Co(0.2-0.3) / MgO(0.8-1.2) / Co(0.7-1.1) / Pt(0.5-0.8) / Co(0.7-1.1) / Pt(0.5-0.8)

[0100] (Embodiment 10) 32 shows a more specific configuration of the bottom pin structure according to the tenth embodiment of the present invention. The magnetoresistive element has a configuration of Pt(>3) / Co(0.5-1.1)(21) / Ir(0.4-0.6)(31) / Fri(0.25-0.6)(41) / Co(0.5-1.1)(22) / Ir(0.4-0.6)(32) / Fri(0.25-0.6)(42) / Co(0.5-1.1)(23) / Ta or W or Mo (0.3) / FeB (1.0-1.4) / ScC (0.8-1.2) / FeB (1.0-1.4) / Ta or W or Mo (0.3) / CoFeB (1.0-1.4) / MgO (0.8-1.2) are arranged in this order. The numerical range in parentheses indicates the range of film thickness (nm). Here, 21, 22, and 23 correspond to the first magnetic layer, second magnetic layer, and third magnetic layer, respectively. 31 and 32 correspond to the first non-magnetic layer and second non-magnetic layer, respectively. 41 and 42 correspond to the first Pt layer and second Pt layer, respectively. In addition to having a non-magnetic layer / Pt layer / magnetic layer configuration, the eighth embodiment is characterized in that a first reference layer (R1) is arranged on the second barrier layer (B2) side of the second fixed layer (P2), and the second barrier layer (B2) is ScC.

[0101] As in the sixth embodiment, in the layer configuration of the tenth embodiment, some or all of the antiferromagnetically coupled magnetic layers (first magnetic layer, second magnetic layer, third magnetic layer) can be multi-layered, and the thickness of each layer, including the Pt layer inserted under the magnetic layers, can be thinned. As in the following example, the first Pt layer and second Pt layer (Pt(0.25-0.6)) in FIG. 32 can be Pt(0.2-0.4), and the second magnetic layer and third magnetic layer (Co(0.5-1.1)) can be Co(0.4-0.6), etc. Pt(>3) / Co(0.4-0.6) / Ir(0.4-0.6) / Fri(0.2-0.4) / Co(0.4-0.6) / Ir(0.4-0.6) / Fri(0.2-0.4) / Co(0.4-0.6) / Ta or W or Mo (0.3) / FeB (1.0-1.4) / ScC (0.8-1.2) / FeB (1.0-1.4) / Ta or W or Mo (0.3) / CoFeB (1.0-1.4) / MgO (0.8-1.2) Furthermore, as shown below, the first Pt layer and second Pt layer (Pt(0.25-0.6)) in Figure 32 can be Pt(0.1-0.2), and the second magnetic layer and third magnetic layer (Co(0.5-1.1)) can be Co(0.2-0.3) / Pt(0.1-0.2) / Co(0.2-0.3), etc. Pt(>3) / Co(0.4-0.6) / Ir(0.4-0.6) / Pt(0.1-0.2) / Co(0.2-0.3) / Pt(0.1-0.2) / Co(0.2-0.3) / Ir(0.4-0.6) / Pt(0.1-0.2) / Co(0.2-0.3)Pt(0.1-0.2) / Co(0.2-0.3) / Ta or W or Mo (0.3) / FeB (1.0-1.4) / ScC (0.8-1.2) / FeB (1.0-1.4) / Ta or W or Mo (0.3) / CoFeB (1.0-1.4) / MgO (0.8-1.2)

[0102] (Embodiment 11) FIG. 33 shows an example of a magnetic memory having a plurality of magnetic memory cells. The magnetic memory includes a memory cell array, an X driver, a Y driver, and a controller. The memory cell array has magnetic memory cells arranged in an array. The X driver is connected to a plurality of word lines WL, and the Y driver is connected to a plurality of bit lines BL, and functions as a read means and a write means.

[0103] (Embodiment 12) 36(a) and 36(b) show a more specific configuration of the twelfth embodiment of the present invention. The structure of Figure 36(a) is Ta(5) / Pt(3) / Co(0.9) / Ir(0.5) / Pt(t Pt ) / Co(0.9) / Ir(0.5) / Pt(t Pt ) / Co(0.9) / Ir / Ta are arranged in this order, and the range of values in parentheses indicates the range of film thickness (nm). The configuration of Figure 36(a) was designed to evaluate an example of the magnetic film of Figure 23. That is, the layers correspond to Co (first magnetic layer (21)) / Ir (first non-magnetic layer (31)) / Pt (first Pt layer (41)) / Co (second magnetic layer (22)) / Ir (second non-magnetic layer (32)) / Pt (second Pt layer (42)) / Co (third magnetic layer (23)). On the other hand, the structure of Figure 36(b) is Ta(5) / Pt(3) / Co(0.9) / Pt(t Pt ) / Ir(0.5) / Co(0.9) / Pt(t Pt ) / Ir (0.5) / Co (0.9) / Ir / Ta are arranged in this order, and the numerical range in parentheses indicates the range of film thickness (nm). The configuration of Figure 36(b) is the magnetic film of Figure 23, with the Pt layer and non-magnetic layer inserted between the magnetic layers reversed. That is, each layer corresponds to Co (first magnetic layer (21)) / Pt (first Pt layer (41)) / Ir (first non-magnetic layer (31)) / Co (second magnetic layer (22)) / Pt (second Pt layer (42)) / Ir (second non-magnetic layer (32)) / Co (third magnetic layer (23)).

[0104] -Evaluation Test 1 of Embodiment 12- First, in FIG. 36(a) and FIG. 36(b), the thickness of the Pt film t Pt An evaluation element with a thickness of 0.6 nm was fabricated and annealed at 300° C. for 1 hour. The magnetization curves obtained for each evaluation element are shown in Figure 37(a) and Figure 37(b), respectively. The magnetization curves are plotted with M / Ms (magnetization divided by saturation magnetization) on the vertical axis and magnetic field H (T) on the horizontal axis, and were obtained by sweeping the magnetic field in the direction perpendicular to and in-plane with respect to the film surface. 37(a) and 37(b), the magnetization curves (solid lines) obtained when the magnetic field was swept perpendicular to the film surface showed a nearly perpendicular loop near zero H. This confirmed that the magnetic layers exhibited perpendicular magnetic anisotropy and that there was good antiferromagnetic coupling between the Co atoms in the magnetic layers. In both the evaluation elements in FIG. 37(a) and FIG. 37(b), the magnetization curves (dotted lines) when a magnetic field was applied in-plane did not show a substantially perpendicular loop when H was zero magnetic field. It was also found that even when annealing was performed at 400° C., good antiferromagnetic coupling was maintained between the Co atoms in the magnetic layers.

[0105] The results of evaluation test 1 of embodiment 12 showed that perpendicular magnetic anisotropy was confirmed even when the stacking order of the nonmagnetic layer and Pt layer was reversed, and that good antiferromagnetic coupling was achieved between the magnetic layers.

[0106] -Evaluation Test 2 of Embodiment 12- Next, in the evaluation element of FIG. 36(a) and FIG. 36(b), the Pt film thickness t Pt The thickness was varied between 0 nm and 1.3 nm, and annealed at 300°C for 1 hour. The external magnetic field H obtained by the evaluation element ex The measurement results are shown in Figure 38. The horizontal axis is the Pt film thickness, and the vertical axis is the external magnetic field H ex is. From Figure 38, when the Pt film thickness is 0.7 nm or less, especially when it is 0.4 nm or less, the external magnetic field H ex It was found that good characteristics were obtained. It was also found that even when annealing was performed at 400° C., good antiferromagnetic coupling was maintained between the Co atoms in the magnetic layers.

[0107] The results of evaluation test 2 of embodiment 12 show that even if Pt is inserted between the antiferromagnetically coupled Co—Ir—Co, a strong external magnetic field can be maintained.

[0108] From the twelfth embodiment, one example of the present invention can be further summarized as shown in FIG. FIG. 39(a) shows part or all of a magnetoresistive effect element with a top-pin structure, in which the lamination order of the first non-magnetic layer (31) and the first Pt layer (41) of FIG. 5 is reversed. FIG. 39(b) shows part or all of a magnetoresistive effect element with a bottom pin structure, in which the lamination order of the first non-magnetic layer (31) and the first Pt layer (41) of FIG. 15 is reversed. FIG. 39(c) shows an adjustment layer disposed on the magnetic layer, with the lamination order of the first non-magnetic layer (31) and the first Pt layer (41) in FIG. 25 reversed. Although not shown, in Figures 6, 7, 8, 9, 16, 17, 18, 19, 21, 26, 27, 28, 29, 30, 31, and 32, which have a configuration in which a non-magnetic layer and a Pt layer are stacked adjacent to each other, similar to Figures 39(a) and 5, Figures 39(b) and 15, and Figures 39(c) and 25, the stacking order of the first non-magnetic layer (31) and the first Pt layer (41), and / or the stacking order of the second non-magnetic layer (32) and the second Pt layer (42), and / or the stacking order of the third non-magnetic layer (33) and the third Pt layer (43), and / or the stacking order of the fourth non-magnetic layer (34) and the fourth Pt layer (44) may be reversed. In other words, when there are multiple adjacently stacked non-magnetic layers and Pt layers, all of the adjacently stacked non-magnetic layers and Pt layers may be stacked in reverse, or only some of them may be stacked in reverse. In the above configuration, the structure, film thickness, materials, etc. are the same as when the stacking order of the adjacent non-magnetic layer and Pt layer is not reversed, except that the stacking order is reversed.

[0109] Although not shown, the following embodiment is also possible as a modified example.

[0110] In the first embodiment shown in FIG. 5, a Pt insertion layer may be inserted between the first magnetic layer (21) and the first non-magnetic layer (31). Similarly, in Figures 6, 7, 8, 9, 15, 16, 17, 18, 19, 21, 25, 26, 27, 28, 29, 30, 31, 32, etc., which have a structure in which magnetic layer (adjusting layer side) / non-magnetic layer / Pt layer / magnetic layer are stacked adjacently in this order, a Pt insertion layer may be inserted between the magnetic layer and non-magnetic layer. Here, if there are multiple structures in which magnetic layer (adjusting layer side) / non-magnetic layer / Pt layer / magnetic layer are stacked adjacently in this order, a Pt insertion layer may be inserted between all of the magnetic layers and non-magnetic layers in the structure in which magnetic layer (adjusting layer side) / non-magnetic layer / Pt layer / magnetic layer are stacked adjacently in this order, or a Pt insertion layer may be inserted between only some of the magnetic layers and non-magnetic layers. The thickness of the Pt insertion layer is preferably in the range of 0.1 nm to 0.9 nm, and more preferably in the range of 0.25 nm to 0.7 nm. The above configuration, except for the Pt insertion layer being inserted between the magnetic layer and the non-magnetic layer, is the same as the case where the Pt insertion layer is not inserted, in terms of configuration, film thickness, material, etc.

[0111] 39(a), 39(b), 39(c), etc., which have a structure in which magnetic layer (adjusting layer side) / Pt layer / non-magnetic layer / magnetic layer are stacked adjacently in this order, a Pt insertion layer may be inserted between the non-magnetic layer and the magnetic layer. Here, if there are multiple structures in which magnetic layer (adjusting layer side) / Pt layer / non-magnetic layer / magnetic layer are stacked adjacently in this order, a Pt insertion layer may be inserted between all of the non-magnetic layers and the magnetic layers in the structures in which magnetic layer (adjusting layer side) / Pt layer / non-magnetic layer / magnetic layer are stacked adjacently in this order, or a Pt insertion layer may be inserted between only some of the non-magnetic layers and the magnetic layers. The above configuration, except for the Pt insertion layer being inserted between the non-magnetic layer and the magnetic layer, is the same as the case where the Pt insertion layer is not inserted, in terms of configuration, film thickness, material, etc. [Explanation of symbols]

[0112] 21 First magnetic layer 22 Second magnetic layer 23 Third magnetic layer 24 Fourth magnetic layer 25 Fifth magnetic layer 26 Sixth magnetic layer 31 First non-magnetic layer 32 Second non-magnetic layer 33 Third non-magnetic layer 34 Fourth non-magnetic layer 35 Fifth non-magnetic layer 41 First Pt layer 42 Second Pt layer 43 Third Pt layer 44 Fourth Pt layer 45 Fifth Pt layer A1 First adjustment layer A2 Second adjustment layer B1 First barrier layer B2 Second barrier layer P1 First fixed layer P2 Second fixed layer R1 First reference layer F1 recording layer E1 lower electrode C1 cap layer H1 Heavy metal layer BL1 First bit line BL2 Second bit line GND Ground line WL Word Line

Claims

1. a first magnetic layer (21); a first non-magnetic layer (31) provided adjacent to the first magnetic layer (21); a first Pt layer (41) provided adjacent to the first nonmagnetic layer (31) on the side opposite to the first magnetic layer (21); a second magnetic layer (22) provided adjacent to the first Pt layer (41) on the side opposite to the first nonmagnetic layer (31); a first adjustment layer (A1) provided adjacent to the first magnetic layer (21) on the side opposite to the first nonmagnetic layer (31); Equipped with The magnetization directions of the first magnetic layer (21) and the second magnetic layer (22) are both perpendicular to the film surface, The first magnetic layer (21) and the second magnetic layer (22) are antiferromagnetically coupled to each other, The thickness of the first Pt layer (41) is in the range of 0.25 to 0.9 nm, The first adjustment layer is a magnetic film containing Pt.

2. 2. The magnetic film according to claim 1, wherein the first magnetic layer (21) and the second magnetic layer (22) have an fcc(111) structure.

3. 3. The magnetic film according to claim 1, wherein the first magnetic layer (21) and the second magnetic layer (22) are made of Co.

4. 4. The magnetic film according to claim 3, wherein the first magnetic layer (21) and the second magnetic layer (22) have a main peak of X-ray diffraction intensity in an X-ray diffraction spectrum where the angle 2θ, which is twice the angle of incidence of X-rays, is between 42° and 43°.

5. 5. The magnetic film according to claim 1, wherein the first non-magnetic layer is made of Ir or Ru.

6. 6. The magnetic film according to claim 5, wherein the thickness of the Ir in the first non-magnetic layer (31) is 0.5±0.15 nm or 1.35±0.1 nm, and the thickness of the Ru is 0.9±0.2 nm or 0.4±0.15 nm.

7. 7. The magnetic film according to claim 1, wherein the second magnetic layer (22) has a thickness greater than the thickness of the first Pt layer (41).

8. a second non-magnetic layer (32) provided adjacent to the second magnetic layer (22) on the side opposite to the first Pt layer (41); a second Pt layer (42) provided adjacent to the second nonmagnetic layer (32) on the side opposite to the second magnetic layer (22); a third magnetic layer (23) provided adjacent to the second Pt layer (42) on the side opposite to the second nonmagnetic layer (32); Furthermore, The magnetization direction of the third magnetic layer (23) is perpendicular to the film surface, 8. The magnetic film according to claim 1, wherein the second magnetic layer (22) and the third magnetic layer (23) are antiferromagnetically coupled to each other.

9. a third non-magnetic layer (33) provided adjacent to the third magnetic layer (23) on the side opposite to the second Pt layer (42); a third Pt layer (43) provided adjacent to the third nonmagnetic layer (33) on the side opposite to the third magnetic layer (23); a fourth magnetic layer (24) provided adjacent to the third Pt layer (43) on the side opposite to the third nonmagnetic layer (33); Furthermore, The magnetization direction of the fourth magnetic layer (24) is perpendicular to the film surface, 9. The magnetic film according to claim 8, wherein the third magnetic layer (23) and the fourth magnetic layer (24) are antiferromagnetically coupled to each other.

10. a fourth non-magnetic layer (34) provided adjacent to the fourth magnetic layer (24) on the side opposite to the third Pt layer (43); a fourth Pt layer (44) provided adjacent to the fourth nonmagnetic layer (34) on the side opposite to the fourth magnetic layer (24); a fifth magnetic layer (25) provided adjacent to the fourth Pt layer (44) on the side opposite to the fourth nonmagnetic layer (34); Furthermore, The magnetization direction of the fifth magnetic layer (25) is perpendicular to the film surface, 10. The magnetic film according to claim 9, wherein the fourth magnetic layer (24) and the fifth magnetic layer (25) are antiferromagnetically coupled to each other.

11. A magnetic recording medium comprising: a first pinned layer (P1) including the magnetic film according to claim 1; a first barrier layer (B1); Equipped with A magnetoresistive element, wherein the first barrier layer (B1) is disposed on the first adjustment layer (A1) side of the first fixed layer (P1).

12. A magnetoresistive effect element as described in Claim 11, wherein the first adjustment layer (A1) is a Co / Pt multilayer film.

13. A second pinned layer (P2) including the magnetic film according to any one of claims 1 to 10; a second barrier layer (B2); Equipped with The magnetoresistive element, wherein the second barrier layer (B2) is disposed on the opposite side of the second fixed layer (P2) to the first adjustment layer (A1).

14. A first fixing layer (P1) according to claim 11 or 12, A first barrier layer (B1) according to claim 11 or 12, a recording layer (F1); A second barrier layer (B2) according to claim 13, A second pinning layer (P2) according to claim 13, Equipped with the first barrier layer (B1) is provided adjacent to the first fixed layer (P1) on the first adjusting layer (A1) side, the recording layer (F1) is provided adjacent to the first barrier layer (B1) on the opposite side to the first fixed layer (P1), the second barrier layer (B2) is provided adjacent to the recording layer (F1) on the opposite side to the first barrier layer (B1), The magnetoresistive element, wherein the second fixed layer (P2) is provided adjacent to the second barrier layer (B2) on the opposite side to the recording layer (F1).

15. A magnetic memory comprising the magnetoresistive element according to any one of claims 11 to 14.

16. The magnetic film according to any one of claims 1 to 10, The stacking order of the first nonmagnetic layer (31) and the first Pt layer (41), and / or The stacking order of the second nonmagnetic layer (32) and the second Pt layer (42), and / or The stacking order of the third nonmagnetic layer (33) and the third Pt layer (43), and / or The stacking order of the fourth nonmagnetic layer (34) and the fourth Pt layer (44), and the magnetic film are opposite in structure.

17. a first pinned layer (P1) including the magnetic film according to claim 16; a first barrier layer (B1); Equipped with A magnetoresistive element, wherein the first barrier layer (B1) is disposed on the first adjustment layer (A1) side of the first fixed layer (P1).

18. A magnetoresistive effect element as described in Claim 17, wherein the first adjustment layer (A1) is a Co / Pt multilayer film.

19. a second pinned layer (P2) including the magnetic film according to claim 16; a second barrier layer (B2); Equipped with The magnetoresistive element, wherein the second barrier layer (B2) is disposed on the opposite side of the second fixed layer (P2) to the first adjustment layer (A1).

20. A magnetic memory comprising the magnetoresistive element according to any one of claims 17 to 19.

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