Electronic devices and related systems, in particular memories, logic devices or neuromorphic devices

Abstract

The invention relates to an electronic device (12) comprising a first electrode (16) with a contact (C5), a ferroelectric subassembly (18) with ferroelectric polarization, a spin-polarized subassembly (22) for spin-polarizing an input current and including a layer of ferromagnetic or ferrimagnetic material, an interface subassembly (20) arranged between the two subassemblies (18, 22) and for converting the spin current into a charge current, the ferroelectric subassembly (18) and the interface subassembly (20) having a contact (C1), and a second electrode (24) with two contacts (C2, C3, C4) defining the polarization subassembly (22), the contact (C5) of the first electrode (16) changing its polarization state by applying a potential difference between this contact (C5) and the other contacts (C1, C2, C3, C4).

Description

[Technical field]

[0001] The present invention relates to electronic devices, in particular memory devices, logic devices, and neuromorphic devices.

[0002] The present invention relates to ferroelectric devices such as memories, logic devices, neuromorphic devices, etc., in particular in the field of information and communication technology. [Background technology]

[0003] Ferroelectrics have polarization. Information can be encoded in the ferroelectric state, and information can be written by applying a voltage. This has given rise to ferroelectric memories, logic devices, and neuromorphic devices.

[0004] One example of a device that utilizes this effect is the ferroelectric random access memory (Fe-RAM). Fe-RAM is a memory device similar to dynamic random access memory (DRAM) with a ferroelectric layer added to make it non-volatile. The advantage of Fe-RAM is that it combines the high speed of random access memory with the non-volatility of flash memory.

[0005] In Fe-RAM, the information to be stored is written by applying a voltage between the two faces of the ferroelectric layer, which encodes the information in the polarization state of the ferroelectric layer.

[0006] Reading is done by applying a voltage and measuring the resulting current. More precisely, a voltage pulse is applied between the two faces of the ferroelectric layer in order to try to switch the polarization from a first state to a second state, for example from state "0" to state "1". If the Fe-RAM was already in state "1", the output current read out is only that associated with the applied voltage pulse. If the Fe-RAM was initially in state "0", the current generated is the sum of the current associated with the voltage pulse and the depolarization current associated with the reversal of the polarization.

[0007] Thus, the read mechanism is destructive: reading erases the stored memory state and, depending on the specific architecture, rewrites the Fe-RAM.

[0008] Therefore, there is a need, especially in memory applications, for a means to read the polarization state of a ferroelectric layer using a non-destructive mechanism.

[0009] To this end, the present specification describes an electronic device comprising a stack stacked along a stacking direction, the stack comprising a first electrode, the first electrode including at least one electrical contact, a ferroelectric subassembly in contact with the first electrode and having a ferroelectric polarization that can assume a plurality of states, a spin-polarized subassembly suitable for spin-polarizing a current flowing through the spin-polarized subassembly, at least one layer of the spin-polarized subassembly being formed of a ferromagnetic or ferrimagnetic material, and an interface subassembly disposed between the ferroelectric subassembly and the spin-polarized subassembly, the interface subassembly suitable for converting the spin-polarized current into a charge current depending on the ferroelectric polarization state of the ferroelectric subassembly. The ferroelectric subassembly and the interface subassembly each have a portion along the stacking direction that is overlapped with the spin-polarized subassembly and a portion that is not overlapped with the spin-polarized subassembly, and at least one of the interface subassembly and the ferroelectric subassembly comprises a conductive layer suitable for forming an intermediate electrode, the intermediate electrode constituting an electrical contact for reading out the polarization state of the ferroelectric subassembly. The stack further comprises a second electrode with at least two electrical contacts for reading out the polarization state of the ferroelectric subassembly, the contacts extending along respective main directions, the at least two main directions being non-parallel to each other, the second electrode defining the spin-polarized subassembly, and the contacts of the first electrode are capable of changing the ferroelectric polarization state of the ferroelectric subassembly by application of a potential difference between the contact and at least one of the contacts of the second electrode or between the contact and the contact of the intermediate electrode.

[0010] According to other particular embodiments, the electronic device has one or more of the following characteristics, taken individually or according to all technically possible combinations: The interface subassembly comprises at least one metal layer or one tunnel barrier or one spin-orbital layer if the ferroelectric subassembly is wholly or partially conductive or semiconductive, or one metal layer or one tunnel barrier or one spin-orbital layer or one two-dimensional electron gas if the ferroelectric subassembly is insulating. The ferroelectric subassembly comprises at least one semiconductive ferroelectric layer or a ferroelectric layer made of a conductive or semiconductive two-dimensional material, and the interface subassembly is bonded to the ferroelectric subassembly and comprises at least one layer. The second electrode is a layer disposed above the spin-polarization subassembly. The second electrode and the spin-polarization subassembly are bonded together. The second electrode includes at least three contacts. Two of the contacts of the second electrode extend along parallel main directions and a third contact of the second electrode extends along a main direction that is substantially perpendicular to the main directions of the other two contacts of the second electrode. The main directions of the contacts between the intermediate electrode and the second electrode are all perpendicular to the lamination direction. The contact of the first electrode is along a direction perpendicular to the stacking direction or along a direction substantially parallel to the stacking direction. The interface subassembly includes at least one of a metal, a Weyl semimetal, a two-dimensional material, a transition metal dichalcogenide, and a topological insulator. The interface subassembly comprises a barrier made of an insulating material, in particular an oxide. The spin-polarized subassembly includes ferromagnetic or ferrimagnetic metal alloys, ferromagnetic or ferrimagnetic oxides, magnetic semiconductors, ferromagnetic or ferrimagnetic composite elements having multiple ferromagnetic or ferrimagnetic layers and metal layers, Heusler alloys, or rare earth-containing ferromagnetic or ferrimagnetic alloys. The ferroelectric substack is an ABO having cations A and B. 3 Materials with a perovskite structure of the type (Hf 1-x ZR x )O 2 , (Hf 1-xGA x )O 2 (x is 0 to 1), or HfO doped with other elements such as Zr or Ga. 2 or alloys thereof, polyvinylidene fluoride, ferroelectric semiconductors, and two-dimensional ferroelectric materials. The contacts perform a readout of the polarization state of the spin-polarized subassembly by applying a readout voltage between two so-called readout contacts selected from the contacts of the intermediate electrode and the contacts of the second electrode and measuring the voltage between the other two so-called readout contacts or between one other so-called readout contact and a reference potential.

[0011] The present specification further describes a system that includes an electronic device, in particular a memory, a logic device, or a neuromorphic device. [Brief description of the drawings]

[0012] The characteristics and advantages of the present invention will become apparent from a reading of the following description, given by way of example only and not by way of limitation, and made with reference to the accompanying drawings, in which: [Figure 1] FIG. 1 is a schematic diagram of an example of an electronic device. [Diagram 2] FIG. 2 is a schematic diagram of another example of an electronic device. [Diagram 3] FIG. 3 is a schematic diagram of another example of an electronic device. [Figure 4] FIG. 4 is a schematic diagram of another example of an electronic device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] For ease of explanation, memory is chosen as the application of the electronic device of the present invention, but it is also possible to fabricate logic devices and neuromorphic devices with such devices.

[0014] Thus, Figure 1 shows an electronic device 12 of a memory 10. The memory 10 further comprises a read unit and a write unit, which are not shown in order to make Figure 1 easier to understand.

[0015] The electronic device 12 includes a laminate 14 .

[0016] The laminate 14 is made up of layers stacked in a stacking direction Z.

[0017] Next, two longitudinal directions perpendicular to the stacking direction Z are defined: a first longitudinal direction X and a second longitudinal direction Y. The two longitudinal directions X, Y are chosen to be mutually orthogonal and to be orthogonal to the reference axes X, Y, Z. The two directions X, Y define a plane parallel to the plane of the stack.

[0018] 1, the relative concepts of bottom and top with respect to stacking direction Z are also defined. When a stack is on the bottom side of the representation of the sheet in FIG. 1, it is located below (below) the other layers, but it should be understood that stacking can be in the opposite direction along direction Z.

[0019] Finally, the thickness of a layer is defined as the dimension along the stacking direction Z of the layer, ie the distance between its two faces.

[0020] In the example shown in FIG. 1, the stack 14 comprises, from the bottom up, a first electrode 16, a ferroelectric subassembly 18, an interface subassembly 20, a spin polarization subassembly 22, and a second electrode 24.

[0021] Hereinafter, for convenience, the first electrode 16 will be referred to as the lower electrode, and the second electrode 24 will be referred to as the upper electrode.

[0022] The electronic device 10 further includes an intermediate electrode 26 having a contact, designated as contact C1 in FIG.

[0023] In this embodiment, the lower electrode 16 includes a contact, indicated as contact C5 in FIG. 1, and the upper electrode 24 includes three contacts in this embodiment (although at least two contacts would be sufficient), such that the electronic device 10 includes at least four contacts.

[0024] In the following, the contact point of the intermediate electrode 26 is referred to as the first contact point C1, the contact points of the upper electrode 24 are referred to as the second contact point C2, the third contact point C3, and the fourth contact point C4, respectively, and the contact point of the lower electrode 16 is referred to as the fifth contact point C5.

[0025] Each of the contacts C1, C2, C3, C4, and C5 is an electrical contact.

[0026] As shown in FIG. 1, each of the contacts C1, C2, C3, C4, C5 is represented in the form of a parallelepiped extending in a main direction.

[0027] Each of the contacts C1, C2, C3, C4 has a respective main direction, but is not limited to this shape.

[0028] According to the embodiment shown in FIG. 1, the bottom electrode 16 includes a fifth contact C5 and a contact layer .

[0029] In an alternative embodiment, the bottom electrode 16 may include multiple contacts.

[0030] In this embodiment, the fifth contact C5 extends mainly along the stacking direction Z.

[0031] In a variant, the fifth contact C5 extends along a direction substantially parallel to the stacking direction Z.

[0032] "Substantially" in this context means equal to within 15 degrees.

[0033] It will become apparent in the following description that the fifth contact C5 makes it possible to change the ferroelectric polarization state of the ferroelectric subassembly 18 by applying a potential difference between contact C5 and at least one of contacts C2, C3 or C4 of the second electrode 24.

[0034] Alternatively, the fifth contact C5 allows the ferroelectric polarization state of the ferroelectric subassembly 18 to be changed by applying a potential difference between this contact C5 and the first contact C1 of the intermediate electrode 26.

[0035] The thickness of the contact layer 28 is typically between 0.2 nanometers (nm) and 100 nm.

[0036] According to this embodiment, the lower electrode 16 is made of a metal material.

[0037] In a variant, the bottom electrode 16 is made of a doped semiconductor material.

[0038] For each electrode 16 or 24, the electrode contact may be made in the same layer as the electrode or may be made independent of the layer forming the electrode, and may or may not be made of the same material as the latter.

[0039] The ferroelectric subassembly 18 has an apparent ferroelectric polarization that can assume multiple states, i.e., the polarization has a nonlinear relationship between the voltage V applied across its faces and the apparent accumulated charge Q following a hysteresis cycle, resulting in at least two residual state subassemblies.

[0040] In the embodiment shown in FIG. 1, the ferroelectric subassembly 18 is in contact with the bottom electrode 16 .

[0041] Ferroelectric subassembly 18 is comprised of a single layer or multiple layers containing one or more materials that impart ferroelectric properties to the resulting stack.

[0042] Several examples of ferroelectric materials that can be used to fabricate at least one layer of the ferroelectric subassembly 18 are now described.

[0043] According to a first embodiment, the ferroelectric material is ABO 3It is an oxide with a perovskite structure of type (A and B are cations).

[0044] This allows the ferroelectric material present in the ferroelectric subassembly 18 to be, for example, BaTiO 3 , PZT (i.e., PbZr 1-x Ti x O 3 where x varies between 0 and 1), PMN-PT (i.e., [1-x]Pb(Mg 1 / 3 N.B. 2 / 3 )O 3 -xPbTiO 3 where x varies between 0 and 1), BiFeO 3 (For example, doping the Bi site with rare earth elements or the Fe site with Mn, as required), SrTiO 3 (optionally doped), KTiO 3 (doped as required), Pr 0,7 Ca 0,3 MnO 3 (doped as required), or YMnO 3 (optionally doped).

[0045] According to a second embodiment, the ferroelectric material is (Hf 1-x Zr x )O 2 , or (Hf 1-x Ga x )O 2 (x varies between 0 and 1), or HfO doped with other elements. 2 , or an alloy thereof.

[0046] The ferroelectric material may be polyvinylidene fluoride.

[0047] In this second embodiment, unlike the first embodiment, the ferroelectric material does not have a perovskite structure.

[0048] According to a third embodiment, the ferroelectric material is a ferroelectric semiconductor.Optionally doped GeTe or AlScN are examples of ferroelectric semiconductor materials.

[0049] According to a fourth embodiment, the ferroelectric material is a two-dimensional ferroelectric material. SnTe or CuInP 2 S 6 is an example of a two-dimensional ferroelectric material.

[0050] In each of the above embodiments, the ferroelectric material can be irradiated, annealed, doped or deposited onto a particular substrate to tailor its ferroelectric and transport properties.

[0051] According to this embodiment, the coercive field of the ferroelectric element and its thickness are small enough to allow the polarization to be reversed at voltages compatible with microelectronics technology, i.e., less than 10 volts (<10V). For the materials mentioned above, a thickness of less than 150 nm, preferably less than 50 nm, can provide such properties. The ferroelectric subassembly 18 can also withstand repeated cycling, typically at least 10 4 Can withstand cycles.

[0052] The spin-polarization subassembly 22 includes at least one magnetic layer made of a ferromagnetic or ferrimagnetic material.

[0053] According to the first case, the magnetic material is a ferromagnetic or ferrimagnetic metal alloy made of elements such as Co, Fe, B, Ni, Al.

[0054] According to the second case, the magnetic material is a ferromagnetic or ferrimagnetic oxide.

[0055] According to a third case, the magnetic material is a magnetic semiconductor.

[0056] According to the fourth case, the magnetic material is [FM / M] nFM type composite ferromagnetic or ferrimagnetic element, ie a stack of several ferromagnetic or ferrimagnetic layers FM and a metal layer M.

[0057] Preferably, n is between 1 and 50.

[0058] A ferromagnetic or ferrimagnetic material FM is, for example, a material in the first three cases.

[0059] The metal material M is selected from, for example, Al, Ta, Ru, Pt, W, Ir, Mo, Ti, Y, and Au.

[0060] According to a fifth case, the magnetic material is a Heusler alloy.

[0061] As an example, the Heusler alloy is 2 MnAl, Cu 2 MnIn, Cu 2 MnSn, NfiMnAl, NfiMnln, NfiMnSn, NfiMnSb, Ni 2 MnGa,Co 2 MnAl, Co 2 MnSi, Co 2 MnGa,Co 2 MnGe, P.D. 2 MnAl, PD 2 MnIn, P.D. 2 MnSn, PD 2 MnSb, Co 2 FeSi, Co 2 FeAl, Fe 2 Val, Mn 2 VGA, Co 2 Selected from FeGe, MnGa, and MnGaRu.

[0062] According to a sixth case, the magnetic material is an alloy containing rare earths.

[0063] For example, the magnetic material is an alloy containing Nd, Sm, Eu, Gd, Tb, and Dy.

[0064] The spin polarization subassembly 22 serves to spin-polarize the charge current flowing through the spin polarization subassembly 22 .

[0065] The spins in the spin polarization subassembly 22 are preferably polarized along a first longitudinal direction X.

[0066] If the remanent magnetization is relatively large, such a spin polarization direction can be obtained by applying a magnetic field along the first longitudinal direction X to saturate the magnetization.

[0067] For magnetically soft materials, in-plane anisotropy can be created, for example, by using magnetic field annealing techniques, by utilizing shape anisotropy, by modifying the surface of the magnetic layer, or by utilizing exchange coupling with an antiferromagnetic layer that is part of the spin polarization subassembly 22.

[0068] Furthermore, the thickness of the ferromagnetic layer is thin (typically less than 100 nm) to optimize the signal read by the read-out unit.

[0069] The spin polarization subassembly 22 is capable of obtaining a relatively high spin polarization, preferably greater than 0.1.

[0070] The ferroelectric subassembly 18 and the spin polarizing subassembly 22 are geometrically arranged in a particular manner.

[0071] In this embodiment, the ferroelectric subassembly 18 has two portions 30 and 32 .

[0072] The first portion 30 is a portion 30 that is superimposed on the spin polarization subassembly 22 along the stacking direction Z.

[0073] In this embodiment, the first portion 30 is a parallelepiped shaped portion.

[0074] The second portion 32 is the portion 32 that is not superimposed on the spin polarization subassembly 22 .

[0075] In this embodiment, the second portion 32 is a T-shaped portion, with the horizontal bar of the T in contact with the first portion 30 and the vertical bar of the T running along a second longitudinal direction Y.

[0076] The interface subassembly 20 defines the ferroelectric subassembly 18 .

[0077] The interface subassembly 20 is disposed between the spin-polarization subassembly 22 and the ferroelectric subassembly 18 . The interface subassembly 20 may be bonded to the ferroelectric subassembly 18 if the ferroelectric subassembly 18 comprises a semiconducting ferroelectric material or a two-dimensional ferroelectric material.

[0078] According to the embodiment shown in FIG. 1, the interface subassembly 20 has two portions 34 and 36 .

[0079] A first portion 34 of the interface subassembly 20 corresponds to the overlying portion 30 of the ferroelectric subassembly 18 .

[0080] As shown, first portion 34 is overlaid on overlapping portion 30 of ferroelectric subassembly 18 .

[0081] The second portion 36 of the interface subassembly 20 corresponds to the non-overlapping portion 32 of the ferroelectric subassembly 18 .

[0082] In this case, the first portion 34 is overlapped with the horizontal bar of the T of the non-overlapping portion 32 of the ferroelectric subassembly 18 .

[0083] In FIG. 1, a first portion 34 of the interface subassembly 20 is thus superimposed on the spin-polarization subassembly 22 along the stacking direction Z, but a second portion 36 of the interface subassembly 20 is not superimposed on the spin-polarization subassembly 22.

[0084] Otherwise, at least one of the interface subassembly 20 and the ferroelectric subassembly 18 includes a conductive layer suitable for forming an intermediate electrode 26, which includes a first contact C1 that is an electrical contact for reading out the polarization state of the ferroelectric subassembly 18.

[0085] According to a first embodiment, the interface subassembly 20 consists of or includes a two-dimensional electron gas.

[0086] According to a second embodiment, the interface subassembly 20 includes one or more interface layers that serve to convert the spin current into a charge current.

[0087] It should be noted that the conversion of spin current to charge current in the interface subassembly 20 can be tuned by the ferroelectricity of the ferroelectric subassembly 18 and can be sufficiently enhanced to minimize the energy consumption of the memory.

[0088] In particular, the interface subassembly 20 includes at least one layer that has a strong spin-orbit effect, referred to as the spin-orbit layer.

[0089] The thickness of the spin-orbital layer is relatively thin, typically less than 10 nm.

[0090] The materials used to create the spin-orbital layer may vary.

[0091] According to a first embodiment, the material of the spin-orbital layer is a material exhibiting the spin Hall effect.

[0092] A material that exhibits the spin Hall effect is a material that can convert a charge current into a spin current, and typically has a spin Hall effect angle of greater than 5%.

[0093] For example, materials that exhibit the spin-orbit spin Hall effect include β-phase tantalum (β-Ta), BiSb, β-tungsten (β-W), W, and Pt.

[0094] According to another example, the material of the spin orbital layer is Cu or Au doped with elements of the 3d, 4d, 5d, 4f, 5f columns of the periodic table, e.g. W, Ta, Bi, or combinations of 5d elements, e.g. PtW, to obtain large spin orbit effects.

[0095] According to a second case, the material of the spin-orbital layer is a two-dimensional spin-orbital material.

[0096] As examples of the second case, the following materials are considered: graphene, BiSe 2 , BiS 2 , BiSe x Te 2-x (x varies between 0 and 2), BiS, TiS, WS 2 , MoS 2 , TiSe 2 , VSe 2 , MoSe 2 , B 2 S3, Sb 2 S, T 0,75 S,Re 2 S 7 , LaCPS 2 , LaOAsS 2 ,ScOBiS 2 , GaOBiS 2 , AIOBiS 2 , LaOSbS 2 , BiOBiS 2 , YOBiS 2 , InOBiS 2 , LaOBiSe 2 , TiOBiS 2 , CeOBiS 2 , PrOBiS 2 , NdOBiS 2 , LaOBiS 2 , or SrFBiS 2 Examples include:

[0097] If desired, the above materials can also be doped.

[0098] According to the third case, the material of the spin-orbital layer is a topological insulator: a material with an insulating strip structure and metallic surface states.

[0099] For example, the material of the spin-orbital layer is Bi 2 SE 3 , BiSbTe, SbTe 3 , HgTe, or α-Sn.

[0100] According to the fourth case, the material of the spin-orbital layer is a Weyl semimetal.

[0101] In such a case, the material of the spin orbital layer is, for example, TaAs, TaP, NbAs, NbP, Na 3 Bi, Cd 3 As 2 , W.T.e. 2 , or MoTe 2 It is.

[0102] Furthermore, ions such as He ions and Ar ions can also be irradiated.

[0103] According to the fifth case, the material of the spin-orbital layer is a transition metal dichalcogenide, preferably ROCh 2 In fact, such materials exhibit a good Rashba effect.

[0104] In this case, "R" is selected from, for example, La, Ce, Pr, Nd, Sr, Ga, Al, and In, and "Ch" is selected from, S, Se, and Te.

[0105] Alternatively or additionally, the interface layer includes one or more non-ferromagnetic metal layers to facilitate conversion of spin current into charge current.

[0106] For example, the interface layer may be formed of a layer of Al, Y, Ru, Mg, Ta, or Ti.

[0107] According to another variant compatible with the above embodiment, the interface layer comprises a barrier made of an insulating material, in particular an oxide.

[0108] Such barriers can be, for example, MgO or Al 2 O 3 which not only improves the spin injection process but also improves the characteristics of the signal read out by the read-out unit.

[0109] In each of the embodiments described above, the interface subassembly 20 contacts a face of the spin polarization subassembly 22 .

[0110] Furthermore, the interface subassembly 20 is adapted to interconvert a spin polarized current into a charge current depending on the ferroelectric polarization state of the ferroelectric subassembly 18 .

[0111] The top electrode 24 includes a metal layer 38 and three contacts: a second contact C2, a third contact C3, and a fourth contact C4.

[0112] The metal layer 38 is in contact with the spin polarization subassembly 22 .

[0113] The three contacts C2, C3, C4 are electrical contacts for reading out the polarization state of the ferroelectric subassembly 18.

[0114] According to this embodiment, the second contact C2 and the fourth contact C4 extend mainly in the same direction, i.e. along the second longitudinal direction Y. The two contacts C2 and C4 are therefore opposite each other.

[0115] The third contact C3 extends mainly along a direction perpendicular to the main direction of the contacts C2 and C4.

[0116] The third contact C3 is electrically connected to the metal layer 38.

[0117] In fact, the first contact C1 is located on the non-overlapped portion 32, more precisely on the vertical bar of the T of the non-overlapped portion 32.

[0118] The first contact C1 electrically connects the interface subassembly 20, and in particular the first portion 34 of the interface subassembly 20.

[0119] Furthermore, the first contact C1 is not covered by the spin polarization subassembly 22 and is therefore accessible from above.

[0120] The first contact C 1 is an electrical contact for reading out the polarization state of the ferroelectric subassembly 18 .

[0121] Next, the operation of the memory 10 will be described.

[0122] When writing, the writing unit charges the contact layer 28 of the bottom electrode 16 .

[0123] For example, the write unit is a transistor, which can charge the contact layer 28 positively or negatively.

[0124] In the first method, during reading, the readout unit applies a current (or a voltage) between the first contact C1 and the third contact C3.

[0125] Because of the particular configuration shown in FIG. 1, the current injected between the first contact C 1 and the third contact C 3 flows entirely from the spin polarization subassembly 22 to the interface subassembly 20 .

[0126] The readout unit then measures the voltage between the second contact C2 and the fourth contact C4, or the voltage between the contact between the second contact C2 and the fourth contact C4 and a reference potential.

[0127] Contrary to the first method, in the second method, the readout unit applies a current (or a voltage) between the second contact C2 and the fourth contact C4, and then measures the voltage between the first contact C1 and the third contact C3, or the voltage between the contact between the contact C1 and the third contact C3 and a reference potential.

[0128] Therefore, in both methods, no current flows through the ferroelectric subassembly 18 .

[0129] Since the ferroelectric subassembly 18 electrically and non-volatilely controls the conversion of spin current to charge current, the measured voltage depends on the injected current and the electric polarization along the stacking direction Z of the ferroelectric subassembly 18.

[0130] The readout unit is suitable for measuring the electric polarization of the ferroelectric subassembly 18 by means of a subunit for injecting a current and a subunit for measuring a voltage.

[0131] This measurement has the special feature of preserving the polarization state of the ferroelectric subassembly 18 and is therefore non-destructive.

[0132] Thus, the memory 10 is a non-destructive read memory.

[0133] 2, 3 and 4, other embodiments of electronic component 10 are possible.

[0134] In this figure, elements common to the embodiment of FIG. 1 are not repeated, but only the differences are emphasized.

[0135] In the case shown in FIG. 2, one of the electrical contacts extending along a direction perpendicular to the direction of the first contact C1 and the third contact C3 is removed.

[0136] Here, only the second contact C2 is maintained.

[0137] In operation, when a read current is injected between the first contact C1 and the third contact C3, charge is transferred through the second contact C2.

[0138] Instead of measuring a voltage as in the embodiment shown in FIG. 1, the readout unit measures the movement of charges, for example by measuring the potential of the second contact C2.

[0139] In the case of FIG. 3, the second, third and fourth contacts C2, C3 and C4 are made on the spin-polarizing subassembly 22, and the upper electrode 38 and the spin-polarizing subassembly 22 are joined.

[0140] Next, another embodiment of the memory will be described with reference to FIG.

[0141] The memory 10 shown in FIG. 4 corresponds to a combination of the memory 10 according to FIGS. 2 and 3 (contacts C2 and C3 are formed in the spin polarizing subassembly 22).

[0142] The electronic device 12 presented for application in memory 10 can also be used as a basic element in other systems, more particularly in logic devices or neuromorphic devices. In the case of neuromorphic devices, the ferroelectric subassembly 18 is designed to have a stable state of partial reversal of apparent electric polarization. Depending on the write voltage and the time the voltage is applied, the state can be made to correspond to different read voltages.

[0143] Electronic device 12 may also be used as a fundamental element in a logic system. The read voltage of a first device is supplied to a second device and used as the write voltage for the second device.

Claims

1. An electronic device (12) comprising a laminate (14) laminated along a stacking direction (Z), the laminate (14) comprising: a first electrode (16) having at least one electrical contact (C5); a ferroelectric subassembly (18) in contact with the first electrode (16) and having a ferroelectric polarization that can assume multiple states; a spin polarization subassembly (22) adapted to spin-polarize a current passing through the spin polarization subassembly (22), at least one layer of the spin polarization subassembly (22) being formed from a ferromagnetic or ferrimagnetic material; an interface subassembly (20) disposed between the ferroelectric subassembly (18) and the spin-polarization subassembly (22), the interface subassembly (20) adapted to interconvert the spin-polarized current into a charge current in response to a ferroelectric polarization state of the ferroelectric subassembly (18); the ferroelectric subassembly (18) and the interface subassembly (20) each have, along the stacking direction (Z), a portion (30, 34) that overlaps the spin-polarization subassembly (22) and a portion (32, 36) that does not overlap the spin-polarization subassembly (22); at least one of the interface subassembly (20) and the ferroelectric subassembly (18) includes a conductive layer suitable for forming an intermediate electrode (26), and the intermediate electrode (26) includes an electrical contact (C1) for reading out the polarization state of the ferroelectric subassembly (18); an interface subassembly (20); a second electrode (24) having at least two electrical contacts (C2, C3, C4) for reading out the polarization state of the ferroelectric subassembly (18), the electrical contacts (C2, C3, C4) each extending along a respective principal direction, the at least two principal directions being non-parallel to one another, the second electrode (24) defining the spin polarization subassembly (22); The electrical contact (C5) of the first electrode (16) allows the ferroelectric polarization state of the ferroelectric subassembly (18) to be changed by application of a potential difference between the electrical contact (C5) and at least one of the electrical contacts (C2, C3, C4) of the second electrode (24) or between the electrical contact (C5) and the electrical contact (C1) of the intermediate electrode (26). A second electrode (24); 1. A device comprising:

2. The interface subassembly (20) comprises at least: If all or part of the ferroelectric subassembly (18) is conductive or semiconductive, it comprises one metal layer, one tunnel barrier, or one spin-orbit layer; or When the ferroelectric subassembly (18) is insulating, it comprises one metal layer, one tunnel barrier, one spin-orbital layer, or one two-dimensional electron gas. The device of claim 1 .

3. 3. The device of claim 2, wherein the ferroelectric subassembly (18) comprises at least one semiconductive ferroelectric layer or a ferroelectric layer of a conductive or semiconductive two-dimensional material, and the interface subassembly (20) is bonded to the ferroelectric subassembly (18) and comprises the at least one layer.

4. The device of any one of claims 1 to 3, wherein the second electrode (24) is a layer disposed above the spin-polarization subassembly (22).

5. The device of any one of claims 1 to 3, wherein the second electrode (24) and the spin-polarization subassembly (22) are joined.

6. 4. A device according to any one of the preceding claims, wherein the second electrode (24) has at least three contacts (C2, C3, C4).

7. 7. The device of claim 6, wherein the two contacts (C2, C4) of the second electrode (24) extend along parallel main directions and the third contact (C3) of the second electrode (24) extends along a main direction that is substantially perpendicular to the main directions of the other two contacts (C2, C4) of the second electrode (24).

8. 4. The device according to claim 1, wherein the main directions of the contacts (C1, C2, C3, C4) of the intermediate electrode (26) and the second electrode (24) are all perpendicular to the stacking direction (Z).

9. 4. The device of claim 1, wherein the electrical contacts (C5) of the first electrodes are either aligned perpendicular to the stacking direction (Z) or aligned substantially parallel to the stacking direction (Z).

10. 4. The device of claim 1, wherein the interface subassembly (20) comprises at least one element selected from the list consisting of metals, Weyl semimetals, two-dimensional materials, transition metal dichalcogenides, and topological insulators.

11. 4. The device according to any one of claims 1 to 3, wherein the interface subassembly (20) comprises a barrier made of an insulating material, in particular an oxide.

12. 4. The device of claim 1, wherein the spin-polarization subassembly (22) comprises a ferromagnetic or ferrimagnetic metal alloy, a ferromagnetic or ferrimagnetic oxide, a magnetic semiconductor, a ferromagnetic or ferrimagnetic composite element having multiple ferromagnetic or ferrimagnetic and metal layers, a Heusler alloy, or a rare earth ferromagnetic or ferrimagnetic alloy.

13. The ferroelectric substack (18), ABO with cations A and B ３ Materials having a perovskite structure of the type (Hf １－ｘ ZR ｘ ) O ２ , (Hf １－ｘ G.A. ｘ ) O ２ (x is 0 to 1), or HfO doped with other elements such as Zr or Ga. ２ , or alloys thereof, polyvinylidene fluoride, a ferroelectric semiconductor, and Two-dimensional ferroelectric materials, 4. A device according to claim 1, comprising a stack of ferroelectric materials selected from the list consisting of:

14. A device as described in any one of claims 1 to 3, wherein the contacts (C1, C2, C3, C4) perform reading of the polarization state of the spin polarization subassembly (22) by applying a read voltage between two so-called read contacts selected from the electrical contact (C1) of the intermediate electrode (26) and the electrical contacts (C2, C3, C4) of the second electrode (24) and measuring the voltage between two other so-called read contacts or between one of the other so-called read contacts and a reference potential.

15. A system, in particular a memory, logic device or neuromorphic device, comprising an electronic device (12) according to any one of claims 1 to 3.

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