Magnetic junction, magnetic device and method for providing a magnetic junction

Abstract

A magnetic junction, a magnetic device, and a method for providing a magnetic junction are described. The magnetic junction includes a free layer and an oxide interlayer located on the free layer. The oxide interlayer includes at least one glass former. In some aspects, the magnetic junction also includes a reference layer and a nonmagnetic spacer layer located between the reference layer and the free layer. The free layer is located between the nonmagnetic spacer layer and the oxide interlayer.

Description

[0001] This application claims priority to U.S. Provisional Patent Application No. 62 / 939,366, filed on November 22, 2019, entitled “OXIDE CAP LAYER CONTAINING GLASS-FORMING ELEMENT,” and U.S. Patent Application No. 16 / 800,779, filed on February 25, 2020, entitled “OXIDE INTERLAYERS CONTAINING GLASS-FORMING AGENTS,” which are hereby incorporated by reference for all purposes. Technical Field

[0002] Embodiments relate to magnetic junctions, magnetic devices, and methods for providing magnetic junctions. Background Art

[0003] Magnetic memories such as magnetic random access memories (MRAM) use magnetic materials as information recording media to store information. For example, magnetic tunnel junctions (MTJs) can be used in MRAMs such as spin transfer torque MRAM (STT-MRAM). MTJs typically reside on a substrate and include a reference layer, a free layer, and a tunnel barrier layer between the reference layer and the free layer. The reference layer and the free layer are magnetic. The magnetic moment of the reference layer is fixed or pinned in a specific direction. The free layer has a variable magnetic moment. The bottom contact under the MTJ and the top contact on the MTJ are used to drive current through the MTJ in the direction of current perpendicular to the plane (CPP) in the STT-MRAM. When sufficient current is driven in a direction perpendicular to the plane (e.g., from top to bottom), the free layer magnetic moment switches to be parallel to the magnetic moment of the reference layer. When sufficient current is driven in the opposite direction (e.g., from bottom to top), the free layer magnetic moment switches to be antiparallel to the magnetic moment of the reference layer. The different magnetic configurations correspond to different magnetic resistances of the MTJ, and thus to different logical states (eg, logical "0" and logical "1") of the MTJ.

[0004] Research into magnetic memories is ongoing due to their potential for use in a variety of applications. Therefore, there is a need for a method and system that can improve the performance of magnetic junctions. Summary of the invention

[0005] One embodiment of the invention is a magnetic junction that includes a free layer and an oxide interlayer on the free layer, the oxide interlayer including at least one glass former.

[0006] Another embodiment of the invention is a magnetic device, comprising a plurality of magnetic junctions and a plurality of wires coupled to the plurality of magnetic junctions, each of the plurality of magnetic junctions comprising a reference layer, a nonmagnetic spacer layer, a free layer, and an oxide interlayer on the free layer, the nonmagnetic spacer layer being between the reference layer and the free layer, the free layer being between the nonmagnetic spacer layer and the oxide interlayer, the oxide interlayer comprising at least one glass former.

[0007] Another embodiment of the invention is a method for providing a magnetic junction, the method comprising the steps of providing a reference layer; providing a nonmagnetic spacer layer; providing a free layer; and providing an oxide interlayer on the free layer, the oxide interlayer comprising at least one glass former. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Various embodiments of the invention are disclosed in the following detailed description and accompanying drawings.

[0009] Figure 1 Embodiments of magnetic junctions having an oxide interlayer including a glass former and useful in magnetic devices such as programmable magnetic memories using spin transfer torque are described.

[0010] Figure 2 is a flow chart depicting an embodiment of a method for providing a magnetic junction having an oxide interlayer including a glass former and useful in a magnetic device such as a programmable magnetic memory using spin transfer torque.

[0011] Figure 3 is a flow chart depicting an embodiment of a method for providing an oxide interlayer that includes a glass former and can be used in a magnetic junction.

[0012] FIG. 4A to FIG. 4C An embodiment of a portion of a magnetic junction during formation of an oxide interlayer including a glass former is depicted.

[0013] Figure 5 is a flow chart depicting another embodiment of a method for providing an oxide interlayer that includes a glass former and can be used in a magnetic junction.

[0014] Figure 6 Another embodiment of a magnetic junction having an oxide interlayer including a glass former and useful in a magnetic device such as a programmable magnetic memory using spin transfer torque is depicted.

[0015] Figure 7 Another embodiment of a magnetic junction having an oxide interlayer including a glass former and useful in a magnetic device such as a programmable magnetic memory using spin transfer torque is depicted.

[0016] Figure 8 Another embodiment of a magnetic junction having an oxide interlayer including a glass former and useful in a magnetic device such as a programmable magnetic memory using spin transfer torque is depicted.

[0017] Fig. 9 Another embodiment of a magnetic junction having an oxide interlayer including a glass former and useful in a magnetic device such as a programmable magnetic memory using spin transfer torque is depicted.

[0018] Fig.10 Exemplary embodiments of a memory utilizing a magnetic junction having a glass-forming element in an oxide layer of a memory element of a memory cell are depicted. DETAILED DESCRIPTION

[0019] Inventions can be implemented in a variety of ways, including as a combination of processes, devices, systems, and substances. In this specification, these embodiments or any other form that the invention can take can be referred to as techniques. In general, the order of steps of the disclosed processes can be changed within the scope of the invention.

[0020] The following together with the attached drawings illustrate the principles of the invention. Figure 1 A detailed description of one or more embodiments of the invention is provided. The invention is described in conjunction with such embodiments, but the invention is not limited to any embodiment. The scope of the invention is limited only by the claims, and the invention encompasses numerous alternatives, modifications, and equivalents. In order to provide a thorough understanding of the invention, numerous specific details are set forth in the following description. These details are provided for illustrative purposes, and the invention may be practiced according to the claims without some or all of these specific details. For the purpose of clarity, technical material known in the technical field related to the invention is not described in detail so that the invention is not unnecessarily obscured.

[0021] Exemplary embodiments are described in the context of specific methods, specific magnetic junctions, and magnetic memories having certain components. The technology described herein is consistent with the use of magnetic junctions and magnetic memories having other and / or additional components and / or other features that are not inconsistent with the present invention. The method and system are also described in the context of the current understanding of spin transfer phenomena, magnetic anisotropy, and other physical phenomena. Therefore, based on this current understanding of spin transfer, magnetic anisotropy, and other physical phenomena, the behavior of the method and system is theoretically explained. However, the technology described herein does not rely on a specific physical explanation. The embodiments are described in the context of a structure having a specific relationship with a substrate. However, the embodiments are consistent with other structures. In addition, the embodiments are described in the context of certain layers being synthetic and / or simple. However, a person of ordinary skill in the art will readily recognize that these layers can have another structure. In addition, the technology is described in the context of magnetic junctions and / or substructures having specific layers. However, magnetic junctions and / or substructures having additional and / or different layers that are not inconsistent with the method and system can also be used. In addition, certain components are described as magnetic, ferromagnetic, and ferrimagnetic. As used herein, the term "magnetic" may include ferromagnetic, ferrimagnetic, or similar structures. Therefore, as used herein, the term "magnetic" or "ferromagnetic" includes, but is not limited to, ferromagnets and ferrimagnets. As used herein, "in-plane" is substantially in the plane of one or more layers of the magnetic junction or substantially parallel to the plane of one or more layers of the magnetic junction. Conversely, "vertical" and "perpendicular to the plane" correspond to a direction substantially perpendicular to one or more layers of the magnetic junction. The method and system are also described in the context of certain alloys. Unless otherwise stated, if the specific concentration of the alloy is not mentioned, any stoichiometry that is not inconsistent with the technology can be used. In addition, various embodiments are described herein. The components described can be combined in a manner not shown and not inconsistent with the method and system.

[0022] Figure 1 An embodiment of a magnetic junction 100 is depicted. For clarity, Figure 1Not to scale. The magnetic junction 100 can be used in magnetic devices such as STT-MRAM, spin-orbit torque MRAM (SOT-MRAM), logic devices, other integrated circuits, and thus in various electronic devices. The magnetic junction 100 is formed on a substrate 101 and includes an optional seed layer 102, a reference layer 110 having a magnetic moment 112, a non-magnetic spacer layer 120, an optional wetting agent 125, a free layer 130 having a magnetic moment 132, an oxide interlayer 140, and an optional cap layer 150. In some embodiments, the cap layer 150 is a metal layer. The bottom contact and top contact are not shown, but can be formed. Similarly, a polarization enhancement layer and other layers may be present, but are not shown for simplicity. As Figure 1 As can be seen in FIG. 1 , the magnetic junction 100 is a bottom pinned magnetic junction. Therefore, the reference layer 110 is closer to the underlying substrate than the free layer 130 ( Figure 1 not shown).

[0023] The reference layer 110 is magnetic. In the illustrated embodiment, the reference layer 110 has a high perpendicular magnetic anisotropy. Therefore, the perpendicular magnetic anisotropy energy of the reference layer 110 is greater than the demagnetization energy out of the plane of the reference layer 110. Therefore, the reference layer magnetic moment 112 is oriented perpendicular to the plane. In other embodiments, the reference layer 110 may not have a high perpendicular magnetic anisotropy. For example, the reference layer 110 may have an in-plane magnetic moment in some embodiments. An optional pinning layer (not shown) may be used to pin the magnetic moment 112 of the reference layer 110. In some embodiments, the optional pinning layer may be an AFM layer or multiple layers that pin the magnetization through an exchange bias interaction. In some embodiments, the optional pinning layer may include a high anisotropic magnetic layer (e.g., one or more CoPt layers and / or CoPd layers) coupled by a metal spacer layer that causes an antiferromagnetic configuration, thereby (as a whole) forming a synthetic antiferromagnetic (SAF) reference layer. However, in other embodiments, the optional pinning layer may be omitted or another structure may be used. In some embodiments, the reference layer 110 does not include a glass former in the as-deposited state.

[0024] The nonmagnetic spacer layer 120 is located between the reference layer 110 and the free layer 130. In some embodiments, the nonmagnetic spacer layer 120 is a tunnel barrier layer. For example, the nonmagnetic spacer layer 120 can be a crystalline MgO layer. In some embodiments where the nonmagnetic spacer layer 120 is a tunnel barrier layer, the resistance of the nonmagnetic spacer layer 120 is much higher than the resistance of the oxide interlayer 140. However, other materials can be used for the nonmagnetic spacer layer 120. For example, the nonmagnetic spacer layer 120 can be conductive, semiconductive, or have another structure.

[0025] The free layer 130 can be prepared on a wetting agent, such as an atomic layer wetting agent 125. Such a wetting agent 125 can include or consist of a 3d transition element, such as V, Cr, Mn, Fe, Co, and / or Ni, which is exposed to oxygen (e.g., oxidation treatment) and / or to another gaseous element or compound that provides a similar wetting function. The formation of the wetting agent 125 is performed before the free layer is deposited. The atomic layer wetting agent 125 can be deposited or prepared on the non-magnetic spacer layer 120. In some embodiments, the wetting agent 125 is thinner than two atomic layers (e.g., less than two angstroms thick). The thickness of such a wetting agent 125 can allow for the presence of a discontinuous layer that allows oxygen atoms to exist in the gaps between / among the nearest pre-deposited ferromagnetic atoms. In some embodiments, the wetting agent 125 can be omitted.

[0026] The free layer 130 is magnetic. Therefore, the free layer 130 may include a ferromagnetic material (such as Fe, Co, CoFe, Co-based Heusler alloys and / or Mn-based Heusler alloys), or be composed of a ferromagnetic material (such as Fe, Co, CoFe, Co-based Heusler alloys and / or Mn-based Heusler alloys). In some embodiments, other and / or additional materials may be used. For example, in some embodiments, ferromagnetic materials and non-magnetic materials may be included in the free layer 130. In the illustrated embodiment, the free layer 130 has a high perpendicular magnetic anisotropy. The perpendicular magnetic anisotropy energy of the free layer 130 is greater than the demagnetization energy out of the plane of the free layer 130. Therefore, the free layer magnetic moment 132 is oriented perpendicular to the plane. In other embodiments, the free layer 130 may not have a high perpendicular magnetic anisotropy. In some embodiments, the free layer 130 is thin. For example, the thickness t of the free layer 130 may be less than thirty angstroms in some embodiments. In some such embodiments, the free layer 130 is no more than fifteen angstroms thick. In some embodiments, the free layer 130 can be at least four angstroms and no more than eight angstroms thick. However, other thicknesses are possible.

[0027] In some embodiments, the free layer 130 does not include a glass former in the deposited state, such as boron. This is in contrast to the CoFeB free layer including deposited B. Therefore, the free layer 130 can be a free layer without boron. In other words, the free layer 130 is a deposited state without boron. In this way, the free layer 130 may not be completely amorphous in the deposited state. The free layer 130 in the deposited state may alternatively be a mixture of crystals or nanocrystals and an amorphous matrix. As used herein for the free layer, the term "crystalline deposited state" refers to a free layer that is at least partially crystalline in the deposited state. In some embodiments, the free layer in the crystallized deposited state is a mostly crystalline deposited state (e.g., more than half of the crystals or nanocrystals). In some such embodiments, the deposited free layer is considered to be completely crystalline. Although described below in the context of a free layer without boron, in some embodiments, the free layer described herein may not contain other and / or all glass forming components when deposited. For example, the free layer 130 may not include B, C, and other glass forming materials that can be used to provide a layer in the deposited state of amorphous. Thus, as used herein, a layer referred to as being free of glass-forming components does not include glass-forming components in the as-deposited state. However, in some embodiments, the free layer 130 may include one or more glass formers.

[0028] The oxide interlayer 140 is located on the free layer 130. In some embodiments, the oxide interlayer 140 is adjacent to the free layer 130 or shares an interface with the free layer 130. In some embodiments, one or more intermediate layers may be located between the free layer 130 and the oxide interlayer 140. The oxide interlayer 140 is an oxide including one or more glass formers. In some embodiments, the oxide interlayer 140 is an oxide of one or more metals such as Mg, Ti, Ta, Zr, Hf, V and / or Nb. In some such embodiments, oxides of Ta, Zr and / or Hf may form a portion of the oxide interlayer 140. The glass former may include one or more of Si, Be, B, Al, P and Ga. In some embodiments, other glass formers may be used in addition to or in place of Si, Be, B, Al, P and / or Ga. In some embodiments, the oxide interlayer 140 includes no more than 50 atomic percent and greater than 0 atomic percent of glass formers. In some embodiments, the oxide interlayer 140 includes no more than 30 atomic percent of glass formers. In some embodiments, oxide interlayer 140 includes at least 5 atomic percent of a glass former. However, other stoichiometries are possible.

[0029] The presence of a glass former causes a material that would otherwise be crystalline to have a more amorphous (e.g., glassy) structure. Thus, oxide interlayer 140 can be at least partially amorphous. In some embodiments, oxide interlayer 140 is mostly (more than half) amorphous. In some embodiments, oxide interlayer 140 can be considered to be completely amorphous. As used herein when describing an oxide layer that includes a glass former, "amorphous" includes partially amorphous, mostly amorphous, and completely amorphous. Thus, oxide interlayer 140 includes a glass former and is amorphous.

[0030] The oxide interlayer 140 may also be thin. In some embodiments, the oxide interlayer 140 is no more than twenty angstroms thick. In some embodiments, the oxide interlayer 140 is less than fifteen angstroms thick. In some embodiments, the oxide interlayer 140 is no more than 12 angstroms thick. For example, the oxide interlayer 140 may be at least six angstroms thick and no more than twelve angstroms thick. In some embodiments, the oxide interlayer 140 is no more than eight angstroms thick.

[0031] The oxide interlayer 140 can improve the performance of the magnetic junction 100. This improvement can have particular utility in the case where the free layer 130 is a free layer without a glass former, such as a free layer without boron. The oxide interlayer 140 can be smooth, continuous, stable, amorphous, and thin. Compared to an oxide layer that does not include a glass former, the oxide interlayer 140 can have reduced roughness, fewer pinholes, and / or fewer voids. The use of a glass former in the oxide interlayer 140 can effectively obtain a more stable amorphous state. Such a high-quality thin oxide layer can prevent or inhibit the diffusion of elements from the layers above the oxide interlayer 140 (e.g., the metal cap layer 150) and / or from the oxide interlayer 140 itself into the free layer 130, or vice versa. For example, the diffusion of Ti, Ta, Zr, Hf, V, and / or Nb can be reduced or prevented. Because the oxide interlayer 140 is amorphous, the lattice mismatch relative to the underlying crystalline layer (such as the free layer 130 without boron) can be mitigated or eliminated. The smooth, continuous and stable layer can also improve the electrical performance of the connection it provides. Therefore, high tunneling magnetoresistance (TMR) and low damping for the free layer 130 can be obtained. Therefore, the oxide interlayer 140 can have improved stability, quality (e.g., increased stability and / or fewer or no voids and / or pinholes) and thinness. The oxide interlayer 140 can also reduce the interdiffusion between the layers 130, 140 and / or 150 and alleviate the lattice mismatch. Therefore, the properties of the free layer 130 and the magnetic junction 100 can be improved.

[0032] The metal capping layer 150 may be a single metal capping layer, a double layer, a triple layer, another multi-layer, or have another structure. Some material categories that can be used for the metal capping layer 150 include refractory metals or high melting point metals (e.g., W, Mo, Ta, Nb, Ru, Ir, Re, Os, Ti, V, Cr, Zr, and / or Hf), metal alloys including glass formers, CoFeB or CoFeB-M (wherein M includes one or more refractory metals), and nitrides (e.g., TaN, TiN, MoN, VN, MnN, NbN, ZrN, HfN, and / or AlN). In some embodiments, at least two of these material categories are combined to form the metal capping layer 150.

[0033] Figure 2 2 is a flow chart depicting an embodiment of a method 200 for providing a magnetic junction having an oxide interlayer including a glass former and useful in a magnetic device such as a programmable magnetic memory using spin transfer torque. For simplicity, some process portions may be omitted, performed in another order, include sub-steps, and / or combined. In addition, method 200 may begin after other processes for forming a magnetic junction have been performed. Typically, layers for the magnetic junction are deposited in a stack, the stack may undergo treatments such as some anneals, a mask layer may be provided on the stack and photolithographically defined, and the edges of the magnetic junction may be defined by etching portions of the layers of the stack exposed by the mask layer. Thus, the processes in method 200 may be staggered.

[0034] A reference layer is provided at 202. In some embodiments, 202 includes depositing a material for the reference layer. In some embodiments, the reference layer is a multilayer, such as a composite reference layer including a non-magnetic layer sandwiched between two magnetic layers. Thus, in such embodiments, 202 includes depositing a plurality of layers. A non-magnetic spacer layer is provided at 204. As an example, 204 may include depositing and crystallizing a MgO or other oxide layer by annealing. In some embodiments, other materials may be deposited as part of 204.

[0035] A free layer is provided at 206. In some embodiments, step 206 includes providing a wetting layer and depositing a free layer material on the wetting layer. Thus, 206 may include depositing approximately two atomic layers of a 3d transition metal and performing a thermal treatment to provide the wetting layer. This process will then be followed by forming a free layer. In addition, 206 may include depositing a free layer that does not contain a glass former. Thus, the free layer material deposited at 206 may be crystalline and in a deposited state that does not contain a glass former. In some embodiments, 206 includes depositing a material such as Fe, Co, CoFe, a Co-based Heusler alloy, and / or a Mn-based Heusler alloy.

[0036] At 208, an oxide interlayer including a glass former is provided on the free layer. In some embodiments, 208 includes depositing a metal layer including a glass former and oxidizing the layer. As described above, the edges of the reference layer, the nonmagnetic spacer layer, the free layer, and the oxide cover can be defined at a later time in the process. Therefore, portions of 202, 204, 206, and 208 can be performed at different times. In some embodiments, 208 includes depositing an oxide layer with a glass former. Fabrication is completed at 210. Thus, additional structures such as metal capping layers, insulating layers, and / or other structures used in the device are fabricated. Other treatments such as annealing or other treatments may also be provided.

[0037] For example, magnetic material and / or other material for reference layer 110 may be provided at 202. Oxide or other material for nonmagnetic spacer layer 120 may be deposited at 204. Free layer 130 may be deposited at 206. Oxide interlayer 140 may be deposited at 208. As part of 210, cap layer 150 may be formed. As part of 202, 204, 206, 208, and 210, a mask (e.g., a hard mask) having openings where it is desired to remove layers for components 110, 120, 130, 140, and 150 may be provided. The mask may be used to etch exposed portions of the layers for components 110, 120, 130, 140, and 150 and form magnetic junction 100. Thus, magnetic junction 100 may be provided and its benefits realized.

[0038] Figure 3 is a flow chart depicting an embodiment of a method 300 for providing an oxide interlayer including a glass former and usable in a magnetic junction. Thus, method 300 may be used in 208 of method 200. For simplicity, some processes may be omitted, performed in another order, include sub-steps, and / or combined. Furthermore, method 300 may be started after other steps of forming a magnetic junction have been performed. FIG. 4A to FIG. 4C An embodiment of a portion of a magnetic junction 400 is depicted during the formation of an oxide interlayer including a glass former. Thus, the method 300 is described in the context of the magnetic junction 400. However, in some embodiments, other devices may be formed.

[0039] At 302, a metal layer is deposited that includes at least one metal and at least one glass former. In some embodiments, the layer is amorphous. In some embodiments, a binary metal / glass former layer is deposited at 302. In some embodiments, the layer deposited at 302 is an alloy. In some embodiments, the layer deposited at 302 may be an amorphous binary alloy layer such as Mg-X, Ti-X, Ta-X, Zr-X, Hf-X, VX, and Nb-X, where X is a glass former. In some embodiments, the glass former is less than or equal to 50 atomic percent of the alloy. In some embodiments, the glass former does not exceed 30 atomic percent of the alloy. In some embodiments, the glass former is at least 5 atomic percent of the alloy. However, other stoichiometries are possible.

[0040] Figure 4A A portion of the magnetic junction 400 is depicted after 302. Thus, the underlying nonmagnetic spacer layer 420 and free layer 430 are shown. Individual compositions 422 (light gray circles) and 432 (dark gray circles) of the nonmagnetic spacer layer 420 and the free layer 430 are shown, respectively. Although the composition 422 of the nonmagnetic spacer layer 420 is depicted as being the same, the composition 422 may represent a variety of different elements, such as Mg and O. Similarly, although the composition 432 of the free layer 430 is depicted as being the same, the composition 432 may represent different elements, such as Co and Fe. In the illustrated embodiment, the layers 420 and 430 are crystalline. Thus, the free layer 430 may be an as-deposited free layer that does not contain a glass former (e.g., does not contain boron). Figure 4A Also depicted in FIG. 4 is an amorphous metal / glass former layer 440. Metal / glass former layer 440 includes metal component 442 (large white circles) and glass former component 444 (small white circles). In some embodiments, component 442 depicts a single metal (e.g., Ti) and component 444 depicts a single glass former (e.g., B). In such embodiments, layer 440 is a binary layer. In other embodiments, component 442 may depict multiple metals and / or component 444 depict multiple glass formers.

[0041] At 304, a natural oxidation or reactive oxidation of the metal / glass former layer 440 is performed. The oxidation may be performed in a single oxidation step or by multiple oxidation steps. Additionally, the deposition at 302 and / or the oxidation at 304 may be repeated at 306 to provide an oxide interlayer of a desired thickness. Figure 4BMagnetic junction 400 is depicted after oxidation at 304 and / or 306. Thus, layer 440' includes oxygen 446 (small black circle). In some embodiments, 304 and / or 306 may include annealing magnetic junction 400. In some embodiments, magnetic junction 400 is annealed later in processing. For example, annealing or thermal treatment may be performed after forming a metal cap layer or after device patterning / fabrication. In some embodiments, at 304 / 306, the magnetic junction is thermally treated as part of the annealing process. Figure 4C The magnetic junction 400 is depicted after a heat treatment in annealing or partial oxidation. Thus, an oxide interlayer 440' is formed including a glass former 444. Oxygen 446 is distributed in the oxide interlayer 440'. Thus, a stable amorphous oxide interlayer 440' is formed. In some cases, some glass formers 444 may diffuse slightly into the free layer 430'. However, as Figure 4C As shown in , the expected diffusion is relatively minimal. At 308, additional layers such as a metal capping layer may also be provided.

[0042] Thus, using method 300, an oxide interlayer such as oxide interlayer 440" may be formed for a magnetic junction such as magnetic junction 400. The oxide interlayer 440" so formed may be thin, stable, amorphous, and continuous. The resistance of oxide interlayer 440" may be much lower than the resistance of non-magnetic spacer layer 420. For example, oxide interlayer 440" may have a resistance that is negligible compared to the resistance of non-magnetic spacer layer 420. Thus, properties such as TMR, stability (e.g., reduced diffusion), and magnetic damping may be improved. Thus, the performance of a magnetic junction so formed (such as magnetic junction 400) may be improved.

[0043] Figure 5 is a flow chart depicting an embodiment of a method 500 for providing an oxide interlayer including a glass former and usable in a magnetic junction. Thus, the method 500 can be used in 208 of the method 200. For simplicity, some processes may be omitted, performed in another order, include sub-steps, and / or combined. In addition, the method 500 may be started after other steps of forming a magnetic junction have been performed.

[0044] At 502, an oxide layer including a glass former may be provided. In some embodiments, 502 includes sputtering an oxide target (e.g., MgO, TiO, or the like) containing a glass former (e.g., Si, Be, B, Al, P, and / or Ga). x 、TaO x 、ZrO x , HfO x , VO x and / or NbO x , where Ox In some embodiments, the glass former is less than or equal to 50 atomic percent of the oxide target. In some embodiments, the glass former is no more than 30 atomic percent of the oxide target. In some embodiments, the glass former is at least 5 atomic percent of the oxide target. However, other stoichiometries are possible. Thus, an oxide interlayer including the glass former is formed. At 504, additional layers such as a metal cap layer may also be provided.

[0045] Using method 500, an oxide interlayer (such as oxide interlayer 140 and / or 440″) for a magnetic junction (such as magnetic junction 100 and / or 400) can be formed. The formed oxide interlayer can be thin, stable, amorphous, and continuous. The resistance of oxide interlayer 140 and / or 440″ can be much lower than the resistance of non-magnetic spacer layer 120 and / or 420. For example, oxide interlayer 140 and / or 440″ can have a negligible resistance compared to the resistance of non-magnetic spacer layer 120 and / or 420. Therefore, properties such as TMR, stability (e.g., reduced diffusion), and magnetic damping can be improved. Therefore, the performance of the magnetic junction (such as magnetic junction 100 and / or 400) so formed can be improved.

[0046] Figure 6 Another embodiment of a magnetic junction 600 having an oxide interlayer including a glass former is depicted. For clarity, Figure 6 Not to scale. The magnetic junction 600 can be used in magnetic devices such as STT-MRAM, spin-orbit torque MRAM (SOT-MRAM), logic devices, other integrated circuits, and thus in a variety of electronic devices. The magnetic junction 600 resides on a substrate 601 and includes an optional seed layer 602, a reference layer 610 having a magnetic moment 612, a free layer 630 having a magnetic moment 632, an oxide interlayer 640, and an optional cap layer 650. In some embodiments, the cap layer 650 is a metal layer. The bottom contact and top contact are not shown, but can be formed. Similarly, a polarization enhancement layer and other layers may be present, but are not shown for simplicity. As Figure 6 As can be seen in FIG. 6 , magnetic junction 600 is a top pinned magnetic junction. Therefore, free layer 630 is closer to the underlying substrate than reference layer 610 ( Figure 6 not shown).

[0047] Reference layer 610 is magnetic and similar to reference layer 110. Therefore, reference layer 610 can have a perpendicular magnetic anisotropy that exceeds the out-of-plane demagnetization energy. Free layer 630 is similar to free layer 130. Therefore, free layer 630 can be a free layer without a glass former. Therefore, free layer 630 can be crystalline. Therefore, seed layer 602 can therefore include a hardener (setting agent). Free layer 630 is magnetic and can include ferromagnetic materials (such as Fe, Co, CoFe, Co-based Heusler alloys and / or Mn-based Heusler alloys) or be composed of ferromagnetic materials (such as Fe, Co, CoFe, Co-based Heusler alloys and / or Mn-based Heusler alloys). In some embodiments, other and / or additional materials can be used. In the illustrated embodiment, free layer 630 has a high perpendicular magnetic anisotropy. In some embodiments, free layer 630 is thin. For example, in some embodiments, the thickness t of free layer 630 can be less than thirty angstroms. In some such embodiments, free layer 630 is no more than fifteen angstroms thick. In some embodiments, the free layer 630 can be at least four angstroms and no more than eight angstroms thick. However, other thicknesses are possible. In some embodiments, the free layer 630 does not contain a deposited glass former, such as boron. Thus, the free layer 630 can be crystalline in the deposited state.

[0048] The oxide interlayer 640 is located on the free layer 630 and also serves as a tunnel barrier layer. The oxide interlayer 640 also includes a glass former as discussed with respect to the oxide interlayers 140 and 440". Therefore, the oxide interlayer 640 is similar to the oxide interlayers 140 and 440". However, it is also expected that the oxide interlayer 640 allows a tunneling magnetoresistance to be formed between the reference layer 610 and the free layer 630. In some embodiments, the oxide interlayer 640 is an oxide of one or more metals (such as Mg, Ti, Ta, Zr, Hf, V and / or Nb). In some such embodiments, oxides of Ta, Zr and / or Hf may form a portion of the oxide interlayer 640. The glass former may include one or more of Si, Be, B, Al, P and Ga. In some embodiments, the oxide interlayer 640 includes no more than 50 atomic percent and greater than 0 atomic percent of a glass former. In some embodiments, the oxide interlayer 640 includes no more than 30 atomic percent of a glass former. In some embodiments, the oxide interlayer 640 includes at least 5 atomic percent of a glass former. However, other stoichiometries are possible. In some embodiments, there may be an oxide interlayer 660 including a glass forming element. Oxide interlayer 660 is similar to oxide interlayer 640, but is located between optional seed layer 602 and free layer 630. Oxide interlayer 660 may be used in addition to or in place of oxide interlayer 640. In some embodiments, oxide interlayer 660 may be omitted.

[0049] The oxide interlayer 640 and the oxide interlayer 660 can improve the performance of the magnetic junction 600. The oxide interlayer 640 can be smooth, continuous, stable, amorphous and thin. The resistance of the oxide interlayer 660 can be much lower than the resistance of the oxide interlayer 640. For example, the oxide interlayer 660 can have a negligible resistance compared to the resistance of the oxide interlayer 640 corresponding to the tunnel barrier layer. Therefore, properties such as TMR, stability (e.g., reduced diffusion) and magnetic damping can be improved. Therefore, the performance of the magnetic junction 600 can be improved.

[0050] Figure 7 Another embodiment of a magnetic junction 700 having an oxide interlayer including a glass former is depicted. For clarity, Figure 7Not to scale. Magnetic junction 700 can be used in magnetic devices such as STT-MRAM, spin-orbit torque MRAM (SOT-MRAM), logic devices, other integrated circuits, and thus in various electronic devices. Magnetic junction 700 resides on substrate 701 and includes an optional seed layer 702, a reference layer 710 having a magnetic moment 712, a nonmagnetic spacer layer 720, a free layer 730 having a magnetic moment 732, an oxide interlayer 740, and an optional cap layer 750. In some embodiments, cap layer 750 is a metal layer. Bottom and top contacts are not shown, but they can be formed. Similarly, polarization enhancement layers and other layers can be present, but are not shown for simplicity. Reference layer 710, nonmagnetic spacer layer 720, and free layer 730 are similar to reference layer 110 / 610, nonmagnetic spacer layer 120, and free layer 130 / 630. Therefore, free layer 730 can be a free layer without a glass former. Reference layer 760, including magnetic moment 762, is similar to reference layer 710. Thus, magnetic junction 700 is a dual magnetic junction.

[0051] The oxide interlayer 740 is located on the free layer 730 and also serves as a tunnel barrier layer. The oxide interlayer 740 also includes a glass former as discussed with respect to the oxide interlayers 140 and 440". Therefore, the oxide interlayer 740 is similar to the oxide interlayers 140 and 440". However, it is also expected that the oxide interlayer 740 allows a tunneling magnetoresistance to be formed between the reference layer 760 and the free layer 730. Therefore, the oxide interlayer 740 is also similar to the oxide interlayer 640. In some embodiments, the oxide interlayer 740 is an oxide of one or more metals (such as Mg, Ti, Ta, Zr, Hf, V and / or Nb). In some such embodiments, oxides of Ta, Zr and / or Hf may form a portion of the oxide interlayer 740. The glass former may include one or more of Si, Be, B, Al, P and Ga. In some embodiments, the oxide interlayer 740 includes no more than 50 atomic percent and greater than 0 atomic percent of a glass former. In some embodiments, the oxide interlayer 740 includes no more than 30 atomic percent of a glass former. In some embodiments, oxide interlayer 740 includes at least 5 atomic percent of a glass former. However, other stoichiometries are possible.

[0052] The oxide interlayer 740 can improve the performance of the magnetic junction 700. The oxide interlayer 740 can be smooth, continuous, stable, amorphous, and thin. The resistance of the oxide interlayer 740 can be much lower than the resistance of the non-magnetic spacer layer 720. For example, the oxide interlayer 740 can have a negligible resistance compared to the resistance of the non-magnetic spacer layer 720. Therefore, properties such as TMR, stability (e.g., reduced diffusion), and magnetic damping can be improved. Therefore, the performance of the magnetic junction 700 can be improved.

[0053] Figure 8 Another embodiment of a magnetic junction 800 having an oxide interlayer including a glass former is depicted. For clarity, Figure 8 Not to scale. Magnetic junction 800 can be used in magnetic devices such as STT-MRAM, spin-orbit torque MRAM (SOT-MRAM), logic devices, other integrated circuits, and thus in various electronic devices. Magnetic junction 800 resides on substrate 801 and includes an optional seed layer 802, a reference layer 810 having a magnetic moment 812, a non-magnetic spacer layer 820, a free layer 830 having a magnetic moment 832, an oxide interlayer 840, and an optional cap layer 850. In some embodiments, cap layer 850 is a metal layer. Bottom and top contacts are not shown, but bottom and top contacts can be formed. Similarly, polarization enhancement layers and other layers can be present, but are not shown for simplicity. Reference layer 810, non-magnetic spacer layer 820, and free layer 830 are similar to reference layer 110 / 610 / 710, non-magnetic spacer layer 120 / 720, and free layer 130 / 630 / 730. In the embodiment shown, free layer 830 may be a free layer without a glass former. In some embodiments, reference layer 810 may be free of a glass former. In the embodiment shown, substrate 801 may be a crystalline substrate such as MgO (001) or Si (001). In some embodiments, layers 802, 810, 820, and 830 are epitaxially grown on a single crystalline substrate. In such embodiments, the deposited layers 802, 810, 820, and 830 should be single crystalline.

[0054] The oxide interlayer 840 is located on the free layer 830 and includes a glass former as discussed with respect to oxide interlayers 140 and 440". Thus, oxide interlayer 840 is similar to oxide interlayers 140 and 440". In some embodiments, oxide interlayer 840 is an oxide of one or more metals (such as Mg, Ti, Ta, Zr, Hf, V and / or Nb). In some such embodiments, oxides of Ta, Zr and / or Hf may form a portion of oxide interlayer 840. The glass former may include one or more of Si, Be, B, Al, P and Ga. In some embodiments, oxide interlayer 840 includes no more than 50 atomic percent and greater than 0 atomic percent of glass former. In some embodiments, oxide interlayer 840 includes no more than 30 atomic percent of glass former. In some embodiments, oxide interlayer 840 includes at least 5 atomic percent of glass former. However, other stoichiometries are also possible.

[0055] A wetting layer 822 is also explicitly shown. The wetting layer 822 may be provided via sputtering, physical vapor deposition (PVD) or other suitable processes, and is used for a free layer 830 that does not contain a glass former. Although depicted as a continuous layer, the wetting layer 822 need not be a continuous layer. The wetting layer 822 includes a material that can be used as a precursor for a subsequent magnetic layer. The wetting layer 822 may include or be composed of a 3d transition metal and / or their alloys. For example, the wetting layer 822 may include at least one of elemental Fe, elemental Co, elemental Ni, elemental Mn, Fe-containing alloys such as CoFe, Co-containing alloys such as CoFe, Ni-containing alloys, and Mn-containing alloys. Optionally, other materials may be optionally included as part of the wetting layer 822. However, any element not included in the subsequent layer that does not contain a glass former may be omitted from the wetting layer 822. In some embodiments, the material used for the wetting layer 822 is magnetic. The wetting layer 822 is also thin. In some embodiments, the wetting layer thickness is at least 0.25 monolayers and no more than three monolayers. In some cases, the thickness can be at least 0.5 monolayers and no more than two monolayers. In some such embodiments, wetting layer 822 has a thickness of at least 0.75 monolayers and no more than 1.25 monolayers. Fractional monolayers correspond to monolayers with holes in them, i.e., incomplete monolayers.

[0056] The oxide interlayer 840 can improve the performance of the magnetic junction 800. The oxide interlayer 840 can be smooth, continuous, stable, amorphous, and thin. The resistance of the oxide interlayer 840 can be much lower than the resistance of the non-magnetic spacer layer 820. For example, the oxide interlayer 840 can have a negligible resistance compared to the resistance of the non-magnetic spacer layer 820. Therefore, properties such as TMR, stability (e.g., reduced diffusion), and magnetic damping can be improved. Therefore, the performance of the magnetic junction 800 can be improved.

[0057] Fig. 9 Another embodiment of a magnetic junction 900 having an oxide interlayer including a glass former is depicted. For clarity, Fig. 9Not to scale. Magnetic junction 900 can be used in magnetic devices such as STT-MRAM, spin-orbit torque MRAM (SOT-MRAM), logic devices, other integrated circuits, and thus in various electronic devices. Magnetic junction 900 resides on substrate 901 and includes an optional seed layer 902, a reference layer 910 having a magnetic moment 912, a nonmagnetic spacer layer 920, an optional wetting layer 922, a hybrid free layer 930, an oxide interlayer 940, and an optional cap layer 950. In some embodiments, cap layer 950 is a metal layer. Bottom and top contacts are not shown, but can be formed. Similarly, polarization enhancement layers and other layers can be present, but are not shown for simplicity. Reference layer 910, nonmagnetic spacer layer 920, and optional wetting layer 922 are similar to reference layer 110 / 610 / 710 / 810, nonmagnetic spacer layer 120 / 720 / 820, and optional wetting layer 822. In some embodiments, reference layer 910 may be free of glass formers.

[0058] In the illustrated embodiment, the free layer 930 is a hybrid free layer including layers 934, 940, and 936. The first free layer 934 has a magnetic moment 932, and the second free layer 936 has a magnetic moment 938. The first free layer 934 and the second free layer 936 are magnetically coupled by the oxide interlayer 940. Therefore, when the magnetic junction 900 is stationary (e.g., not being written), the magnetic moments 932 and 938 are aligned in parallel. The first free layer 934 is similar to the free layer 130 / 630 / 730 / 830. Therefore, the first free layer 934 can be a free layer without a glass former. The oxide interlayer 940 is similar to the oxide interlayers 140, 640, 740, and / or 840. Therefore, the oxide interlayer 940 is located on the first free layer 934 and includes a glass former as discussed with respect to the oxide interlayers 140 and 440". Therefore, the oxide interlayer 940 is similar to the oxide interlayers 140 and 440". In some embodiments, the oxide interlayer 940 is an oxide of one or more metals such as Mg, Ti, Ta, Zr, Hf, V and / or Nb. In some such embodiments, oxides of Ta, Zr and / or Hf may form a portion of the oxide interlayer 940. The glass former may include one or more of Si, Be, B, Al, P and Ga. In some embodiments, the oxide interlayer 940 includes no more than 50 atomic percent and greater than 0 atomic percent of the glass former. In some embodiments, the oxide interlayer 940 includes no more than 30 atomic percent of the glass former. In some embodiments, the oxide interlayer 940 includes at least 5 atomic percent of the glass former. However, other stoichiometries are also possible. In addition, the oxide interlayer 940 forms a coupling layer between the first free layer 934 and the second free layer 936. The second free layer 936 may be configured as desired. For example, the second free layer 936 may be a CoFeB free layer.

[0059] The thin non-magnetic spacer layer 960 can be an insulator or a conductor. For example, the thin non-magnetic spacer layer 960 can be an oxide or a metal. The resistance of the thin non-magnetic spacer layer 960 is significantly less than the resistance of the non-magnetic spacer layer 920. In some embodiments, the resistance of the thin non-magnetic spacer layer 960 is negligible compared to the resistance of the non-magnetic spacer layer 920.

[0060] The oxide interlayer 940 can improve the performance of the magnetic junction 900. The oxide interlayer 940 can be smooth, continuous, stable, amorphous, and thin. The resistance of the oxide interlayer 940 can be much lower than the resistance of the non-magnetic spacer layer 920. For example, the oxide interlayer 940 can have a negligible resistance compared to the resistance of the non-magnetic spacer layer 920. Therefore, properties such as TMR, stability (e.g., reduced diffusion), and magnetic damping can be improved. Therefore, the performance of the magnetic junction 900 can be improved.

[0061] Fig.10 An exemplary embodiment of a memory 1000 that can use a magnetic junction having an oxide layer including a glass former is depicted. The memory 1000 can use the magnetic junction 100, 400 ( FIG. 4A to FIG. 4C ), 600, 700, 800, 900 and / or one or more of other magnetic junctions including an oxide layer having a glass former. In other embodiments, the memory may have a different configuration and / or utilize a different mechanism to read and / or write the magnetic junction. The memory 1000 includes read / write column select drivers 1002 and 1006 and a word line select driver 1004. Note that other components and / or different components may be provided. The storage area of ​​the memory 1000 includes magnetic storage cells 1010. Each magnetic storage cell 1010 includes at least one magnetic junction 1012 used as a memory element (e.g., for storing data) and at least one selection device 1014. The selection device 1014 is enabled by line 1005, while line 1003 is used for the magnetic junction 1012. In some embodiments, the selection device 1014 is a transistor. The magnetic junction 1012 may be a magnetic junction 100, 400 ( FIG. 4A to FIG. 4C ), 600, 700, 800, 900, and / or one of other magnetic junctions including an oxide layer having a glass former. Although one magnetic junction 1012 is shown for each magnetic storage unit 1010, in other embodiments, another number of magnetic junctions 1012 may be provided for each magnetic storage unit. In this way, the memory 1000 may enjoy the above-mentioned benefits.

[0062] Although the foregoing embodiments have been described in some detail for purposes of clarity of understanding, the invention is not limited to the details provided. There are many alternative ways of implementing the invention. The disclosed embodiments are illustrative rather than restrictive.

Claims

1. A magnetic junction, comprising: Free layer; as well as an oxide interlayer, located on the free layer, the oxide interlayer being an oxide including a metal element and at least one glass former, wherein the at least one glass former is selected from Si, Be, B, P and Ga, Wherein, the metal element is not Be and Ga, and Wherein, the oxide interlayer comprises at least 5 atomic percent and no more than 50 atomic percent of the at least one glass former.

2. The magnetic junction according to claim 1, wherein: The metal element includes at least one of Mg, Ti, Ta, Zr, Hf, V and Nb.

3. A magnetic junction, comprising: Free layer; as well as an oxide interlayer disposed on the free layer, the oxide interlayer comprising a metal oxide and at least one glass former, wherein the at least one glass former is selected from Si, Be, B, P and Ga, wherein the metal is not Be and Ga, and Wherein, the oxide interlayer comprises at least 5 atomic percent and no more than 50 atomic percent of the at least one glass former.

4. The magnetic junction according to claim 3, wherein: The metal includes at least one of Mg, Ti, Ta, Zr, Hf, V and Nb.

5. The magnetic junction according to claim 1 or 3, further comprising: Reference layer; as well as A non-magnetic spacer layer is located between the reference layer and the free layer, and the free layer is located between the non-magnetic spacer layer and the oxide interlayer.

6. The magnetic junction according to claim 1 or 3, wherein: The free layer is a boron-free free layer.

7. The magnetic junction according to claim 1 or 3, wherein: The oxide interlayer includes no more than 30 atomic percent of the at least one glass former.

8. The magnetic junction according to claim 1 or 3, wherein: The oxide interlayer shares an interface with the free layer.

9. The magnetic junction according to claim 1 or 3, wherein: The oxide interlayer is amorphous.

10. The magnetic junction according to claim 1 or 3, further comprising: The substrate, the free layer resides between the oxide interlayer and the substrate.

11. A magnetic device, comprising: a plurality of magnetic junctions, each of the plurality of magnetic junctions comprising a reference layer, a nonmagnetic spacer layer, a free layer, and an oxide interlayer on the free layer, the nonmagnetic spacer layer being between the reference layer and the free layer, the free layer being between the nonmagnetic spacer layer and the oxide interlayer, the oxide interlayer being an oxide comprising a metal element and at least one glass former; and a plurality of conductive wires coupled to the plurality of magnetic junctions; wherein the at least one glass former is selected from Si, Be, B, P and Ga, Wherein, the metal element is not Be and Ga, and Wherein, the oxide interlayer comprises at least 5 atomic percent and no more than 50 atomic percent of the at least one glass former.

12. The magnetic device according to claim 11, wherein: The metal element includes at least one of Mg, Ti, Ta, Zr, Hf, V and Nb.

13. A magnetic device, comprising: a plurality of magnetic junctions, each of the plurality of magnetic junctions comprising a reference layer, a nonmagnetic spacer layer, a free layer, and an oxide interlayer on the free layer, the nonmagnetic spacer layer being between the reference layer and the free layer, the free layer being between the nonmagnetic spacer layer and the oxide interlayer, the oxide interlayer comprising an oxide of a metal and at least one glass former; and a plurality of conductive wires coupled to the plurality of magnetic junctions; wherein the at least one glass former is selected from Si, Be, B, P and Ga, wherein the metal is not Be and Ga, and Wherein, the oxide interlayer comprises at least 5 atomic percent and no more than 50 atomic percent of the at least one glass former.

14. The magnetic device according to claim 13, wherein: The metal includes at least one of Mg, Ti, Ta, Zr, Hf, V and Nb.

15. The magnetic device according to claim 11 or 13, wherein: The free layer is a boron-free free layer.

16. The magnetic device according to claim 11 or 13, wherein: The oxide interlayer includes no more than 30 atomic percent of the at least one glass former.

17. The magnetic device according to claim 11 or 13, wherein: The oxide interlayer is amorphous.

18. The magnetic device according to claim 11 or 13, further comprising: A substrate, a free layer for each of the plurality of magnetic junctions residing between the oxide interlayer and the substrate.

19. A method for providing a magnetic junction, the method comprising the steps of: Provide a reference layer; providing a non-magnetic spacer layer; Provides a free tier; as well as providing an oxide interlayer on the free layer, the oxide interlayer being an oxide including a metal element and at least one glass former, wherein the at least one glass former is selected from Si, Be, B, P and Ga, Wherein, the metal element is not Be and Ga, and Wherein, the oxide interlayer comprises at least 5 atomic percent and no more than 50 atomic percent of the at least one glass former.

20. The method according to claim 19, wherein: The step of providing an oxide interlayer comprises at least one of a first process and a second process, wherein the first process comprises: depositing a metal layer comprising the metallic element and the at least one glass former; and Oxidizing the metal layer; The second process includes depositing an oxide capping layer.

21. The method according to claim 19, wherein: The metal element includes at least one of Mg, Ti, Ta, Zr, Hf, V and Nb.

22. A method for providing a magnetic junction, the method comprising the steps of: Provide a reference layer; providing a non-magnetic spacer layer; Provides a free tier; as well as providing an oxide interlayer on the free layer, the oxide interlayer comprising an oxide of a metal and at least one glass former, wherein the at least one glass former is selected from Si, Be, B, P and Ga, wherein the metal is not Be and Ga, and Wherein, the oxide interlayer comprises at least 5 atomic percent and no more than 50 atomic percent of the at least one glass former.

23. The method according to claim 22, wherein: The step of providing the oxide interlayer comprises at least one of a first process and a second process, The first process comprises providing a layer comprising an oxide of the metal and the at least one glass former by sputtering, and The second process includes depositing an oxide capping layer.

24. The method according to claim 22, wherein: The metal includes at least one of Mg, Ti, Ta, Zr, Hf, V and Nb.

25. The method according to claim 19 or 22, wherein: The step of providing a free layer includes providing a free layer that does not contain boron.

26. The method according to claim 19 or 22, wherein: The oxide interlayer includes no more than 30 atomic percent of the at least one glass former.

27. The method according to claim 19 or 22, wherein: The oxide interlayer is amorphous.

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