Magneto-electric device controllable by an adjustable magnetic field

Abstract

The invention relates to a magneto-electric device (10) comprising: a substrate (12); a magneto-electronic module (14) secured to the substrate; electronic connections (16, 18) to the magneto-electronic module; a magnetic element arranged at a non-zero distance from the magneto-electronic module; and an actuating member (24) capable of modifying the non-zero distance. The device further comprises uprights (30) arranged on either side of the magneto-electronic module; the actuating member comprises a conductive electrode (34) arranged on the magneto-electronic module (14) and between the uprights; and the magnetic element comprises a suspended membrane (22) extending between the uprights, facing the electrode; the membrane being capable of being elastically deformed under the effect of an electric voltage applied between the membrane and the electrode, so as to move the membrane toward and / or away from the electrode.

Description

[0001] DESCRIPTION

[0002] Adjustable magnetic field controllable magneto-electric device

[0003] The present invention relates to a magneto-electric device of the type comprising: a substrate including a principal surface, substantially flat; a magneto-electronic module, integral with the principal surface of the substrate; said module being capable of analyzing and / or generating and / or propagating and / or conditioning an electronic signal; a first and a second electronic connection to the magneto-electronic module; a magnetic element, disposed at a non-zero distance from the magneto-electronic module; and an actuation member, capable of modifying the non-zero distance between said magnetic element and the magneto-electronic module.

[0004] The invention is particularly applicable to MEMS (Micro Electro-Mechanical system) type electromechanical devices. Such a device is described in particular in document WO2023 / 067563.

[0005] Magnetoelectric devices, particularly magnonic and spintronic devices, offer numerous advantages for radio frequency and signal processing applications. These devices are miniaturizable, reconfigurable, and energy-efficient. Reconfiguration is achieved primarily through the application of a magnetic field that can be modified on demand to control the device's operating point.

[0006] However, the techniques considered so far for applying such fields require the use of large electromagnets, which is not compatible with the insertion of such devices into integrated circuits.

[0007] The present invention aims to provide a magneto-electric device that can be controlled by applying a continuous magnetic field adjustable by means of an applied voltage and allowing incorporation into an integrated circuit.

[0008] To this end, the invention relates to a magneto-electric device of the aforementioned type, further comprising a first and a second upright, each of said uprights extending from the main surface of the substrate to a free end, distant from said main surface; the first and second uprights being arranged on either side of the magneto-electronic module in a first direction. The actuation member comprises a conductive electrode, disposed on the magneto-electronic module and between the first and second uprights in the first direction Y; and the magnetic element comprises a suspended membrane, extending between the free ends of the first and second uprights, opposite the electrode; said membrane being capable of being elastically deformed under the effect of an electrical voltage applied between said membrane and the electrode, so as to bring said membrane closer to and / or further away from said electrode.

[0009] According to other advantageous aspects of the invention, the magneto-electric device comprises one or more of the following characteristics, taken individually or in all technically possible combinations:

[0010] - The magneto-electric device is configured such that: for a zero electrical voltage between the membrane and the electrode, the distance between said membrane and said electrode is equal to a first value do; for an electrical voltage greater than or equal to a threshold value T s non-zero, between the membrane and the electrode, the distance between said membrane and said electrode is equal to a second value di, less than the first value do; and for an electrical voltage T, non-zero and less than the threshold value T s , between the membrane and the electrode, the distance between said membrane and said electrode is equal to a third value d2 such that di < d2 < do;

[0011] - the magneto-electric device is configured so that, when the electrical voltage T between the membrane and the electrode is less than the threshold value T s , a difference (do - d2) is approximately proportional to T;

[0012] - the membrane and the first and second uprights are formed from a single piece;

[0013] - the magneto-electronic module comprises one or more layers of materials, magnetic or non-magnetic, suitable for the propagation of spin-polarized currents, spin or spin waves;

[0014] - a dimension of the membrane along a second direction, perpendicular to the first direction, is less than or equal to a dimension of the conducting electrode along said second direction;

[0015] - a dimension of the membrane along a second direction X, perpendicular to the first direction Y, is greater than a dimension of the conducting electrode along said second direction;

[0016] - the magneto-electric device comprises a plurality of magneto-electronic modules arranged on the substrate and connected to each other, each module being associated with a conductive electrode, arranged on said module, and with a membrane suspended above said module, each membrane being capable of being elastically deformed under the effect of an electrical voltage applied between said membrane and the corresponding electrode;

[0017] - the substrate is suitable for the propagation of spin waves, the magneto-electronic module being formed by a central zone of said substrate; and the first and second electronic connections to the magneto-electronic module are formed respectively by a first and a second spin wave transducer, arranged on the main surface of the substrate, on either side of the central zone in a second direction, perpendicular to the first direction;

[0018] - the first and second electronic connections are separated by a length L along the second direction; and the dimension of the membrane along said second direction is greater than or equal to 0.90*L, preferably greater than or equal to 0.95*L.

[0019] The invention further relates to a method for manufacturing a magneto-electric device as described above, comprising the following steps: deposition of the conductive electrode onto the magneto-electronic module; then deposition of a first mask onto the substrate and the electrode; then deposition of a magnetic material onto the substrate and the first mask; then deposition of a second mask onto said magnetic material; then removal of portions of the magnetic material, distant from the first and second masks; then removal of the second and first masks, the magnetic material thus exposed forming the membrane and the first and second supports. Preferably, the electronic connections are deposited onto the substrate before the deposition of the first mask onto the substrate and the electrode.

[0020] The invention will be better understood upon reading the following description, given solely by way of non-limiting example and made with reference to the drawings in which:

[0021] - Figure 1 is a schematic top view of a magneto-electric device according to a first embodiment of the invention;

[0022] - Figure 2 is a cross-sectional view of the magneto-electric device of Figure 1, in a first configuration;

[0023] - Figure 3 is a schematic top view of a magneto-electric device according to a second embodiment of the invention;

[0024] - Figures 4 and 5 are cross-sectional views of the magneto-electric device of Figure 3, respectively in a second and a third configuration;

[0025] - Figure 6 is a schematic top view of a magneto-electric device according to a third embodiment of the invention;

[0026] - Figure 7 is a schematic, cross-sectional view of a manufacturing step in the magneto-electric device shown in Figures 3 to 5; and

[0027] - Figure 8 represents simulated data curves of use of the magneto-electric device of figures 3 to 5.

[0028] Figures 1 and 2 depict a magnetoelectric device 10 according to a first embodiment of the invention. Figures 3 to 5 depict a magnetoelectric device 110 according to a second embodiment of the invention. Devices 10 and 110 will be described simultaneously below, with common elements designated by the same reference numbers.

[0029] The magneto-electric device 10, 110 comprises: a substrate 12, 112; a magneto-electronic module 14, 114; a first 16, 116 and a second 18, 118 connection; a support structure 20, 120; a magnetic element 22, 122; and an actuation member 24, 124.

[0030] The substrate 12, 112 comprises a principal surface 26, 126, which is substantially flat. In the following description, an orthonormal basis (X, Y, Z) is considered associated with the substrate 12, 112, with the principal surface 26, 126 extending along a plane (X, Y).

[0031] The magneto-electronic module 14, 114 is attached to the main surface 26, 126 of the substrate 12, 112. Said magneto-electronic module 14, 114 is in particular capable of analyzing and / or generating and / or propagating and / or conditioning an electronic signal, as will be detailed below.

[0032] Preferably, the magneto-electronic module 14,114 comprises one or more layers of materials, magnetic or non-magnetic, suitable for the propagation of spin-polarized currents, spin waves, or spin waves. Preferably, the magneto-electronic module 14,114 is a spintronic device, for example, a magnonic device or a spin-transfer magnetic tunnel junction or spin-orbit couple.

[0033] The first 16, 116 and second 18, 118 connections are electronic connections to the magneto-electronic module 14, 114. In the embodiment shown, the first 16, 116 and second 18, 118 connections are arranged on the main surface 26, 126 of the substrate 12, 112. Preferably, the first 16, 116 and second 18, 118 connections are substantially arranged on either side of the magneto-electronic module 14, 114, along the X direction, referred to as the longitudinal direction.

[0034] The support structure 20, 120 includes two uprights 30, 130, arranged on either side of the magneto-electronic module 14, 114 along the Y direction, known as the transverse direction.

[0035] Each of the said amounts 30, 130 extends from the main surface 26, 126 of the substrate 12, 112 in the Z direction.

[0036] In the following description, the Z direction is considered to be vertical. More precisely, terms such as "on", "under", "above" or "below" are understood with respect to the Z direction.

[0037] More precisely, each amount 30, 130 extends to a free end 32, 132, distant along Z from the main surface 26, 126 of the substrate 12, 112.

[0038] The magnetic element of the device 10, 110 is in the form of a suspended membrane 22, 122. More precisely, said membrane 22, 122 extends between the free ends 32, 132 of the uprights 30, 130, above the module 14, 114. The membrane 22, 122 will be described in more detail below.

[0039] The actuation member 24, 124 of the device 10, 110 comprises a conductive electrode 34, 134, disposed on the magneto-electronic module 14, 114. More precisely, the electrode 34, 134 is disposed between the uprights 30, 130 in the transverse direction Y.

[0040] In the embodiments shown, the actuation member 24, 124 further includes a third 36, 136 and a fourth 38, 138 connection, arranged on the main surface 26, 126 of the substrate 12, 112 and forming electrical connections to the electrode 34, 134.

[0041] Optionally, as seen in Figures 4 and 5, the actuation member 124 further includes a layer 140 of a dielectric material, covering the electrode 134.

[0042] The membrane 22, 122, suspended between the uprights 30, 130, is disposed at a non-zero distance from the magneto-electronic module 14, 114 in the Z direction. More precisely, the membrane 22, 122 is disposed at a distance 42 along Z from the electrode 34, 134, disposed on the module 14, 114.

[0043] The membrane 22, 122 is capable of being elastically deformed under the effect of an electrical voltage applied between said membrane 22, 122 and the electrode 34, 134, so as to bring said membrane closer to and / or further away from said electrode. The magnetic element of the device 10, 110 is thus of the MEMS type.

[0044] In a first configuration of the device 10, 110, a zero electrical voltage is applied between the membrane 22, 122 and the electrode 34, 134; and the distance 42 between said membrane and said electrode is equal to a first value do. As an example, Figure 2 represents the device 10 in the first configuration.

[0045] In a second configuration of the device 10, 110, an electrical voltage greater than or equal to a threshold value T s A non-zero pressure is applied between the membrane 22, 122 and the electrode 34, 134; and the distance between said membrane and said electrode is equal to a second value di, less than the first value do. As an example, Figure 4 represents the device 110 in the second configuration.

[0046] In the case where electrode 134 is covered with layer 140 of dielectric material, the second configuration of device 10, 110 corresponds to contact between membrane 22, 122 and said layer 140. The second value di is then non-zero. Layer 140 thus prevents the membrane from sticking to the electrode in case of contact. In the absence of layer 140 of dielectric material on electrode 34, 134, the second configuration of device 10, 110 can lead to contact between membrane 22, 122 and said electrode, which would correspond to an irreversible RF switch function.

[0047] In a third configuration of the device 10, 110, an electrical voltage T, non-zero and less than the threshold value T s, is applied between the membrane 22, 122 and the electrode 34, 134; and the distance between said membrane and said electrode is equal to a third value d2 such that di < d2 < do. As an example, Figure 5 represents the device 110 in the third configuration.

[0048] According to one embodiment, when the electrical voltage T between the membrane 22, 122 and the electrode 34, 134 is less than the threshold value T s , a difference between the first value do and the third value d2 is substantially proportional to T.

[0049] In an embodiment not shown, the device 10, 110 is configured so that the distance 42 between the membrane 22, 122 and the electrode 34, 134 can be increased beyond do. For this purpose, an additional electrode (not shown) is, for example, arranged above the membrane 22, 122, opposite the electrode 34, 134.

[0050] According to one embodiment, the membrane 22, 122 is formed of a hard magnetic material, preferably with a strong uniaxial or cubic magnetocrystalline anisotropy, for example SmCo. Such a material is capable of forming a permanent magnet.

[0051] According to another embodiment, the membrane 22, 122 is formed of a soft magnetic material, for example iron, cobalt or an iron-nickel alloy NiFe.

[0052] The thickness along the Z-axis of the membrane 22, 122 is, for example, on the order of 1 µm. According to one embodiment, the membrane 22, 122 and the uprights 30, 130 are formed as a single piece. A manufacturing process for such an embodiment will be detailed later.

[0053] According to a first embodiment, as seen in Figure 1 for device 10, a dimension 50 of the membrane 22, 122 along the longitudinal direction X is less than or equal to a dimension 52 of the electrode 34, 134 along said longitudinal direction.

[0054] According to a second embodiment, as shown in Figure 3 for device 110, a dimension 150 of the membrane 22, 122 along the longitudinal direction X is greater than a dimension 152 of the electrode 34, 134 along said longitudinal direction. In other words, according to said second embodiment, a projection of the membrane 22, 122 onto the main surface 26, 126 of the substrate 12, 112 completely covers the electrode 34, 134.

[0055] Electrode 34, 134, for example, is made of platinum. The thickness along Z of electrode 34, 134 is, for example, on the order of 10 nm.

[0056] The optional layer 140 is for example made of SisN4, Al2O3 or SiC>2. A thickness of said layer 140 is for example on the order of 10 nm to 50 nm.

[0057] The magneto-electric device 10 in Figures 1 and 2 will now be described in more detail.

[0058] The substrate 12 of the device 10 is formed of an inert material, for example chosen from silicon (Si), high resistivity silicon (SiHR), glass, doped or undoped gadolinium-gallium garnets (GGG), YSGGG, Al2O3 sapphires, magnesium oxide MgO, DSO (DyScOs), GSO (GdScOs) and strontium titanate STO (SrTiOs).

[0059] Module 14 is fixed to the main surface 26 of the substrate 12 and forms a relief in relation to said main surface.

[0060] The magneto-electronic module 14 is, for example, an RF spintronic resonator, analogous to those described in documents US8227099 and W02020021004.

[0061] In the embodiment of Figures 1 and 2, the uprights 30 have a planar shape. More precisely, each upright 30 has two opposite principal faces, each of said faces extending substantially in a plane (Y, Z).

[0062] Other configurations can be considered for the uprights 30 and the membrane 22 of the device 10. In particular, the configuration described below, for the uprights 130 and the membrane 122 of the device 110, can be adapted to the device 10.

[0063] The first 16 and second 18 electronic connections to the module 14 extend over the main surface 26 of the substrate 12 to one end in contact with said module 14. In the embodiment shown, the first 16 and second 18 connections extend linearly along the longitudinal direction X. Other configurations may be considered.

[0064] In Figure 1, the third 36 and fourth 38 electrical connections of electrode 34 are shown parallel to the first 16 and second 18 electronic connections. According to one variant, the first 16 and third 36 connections coincide. According to a second variant, the second 18 and fourth 38 connections coincide.

[0065] In particular, if module 14 is an RF spintronic resonator, one of the first 16 and second 18 connections to said module is, for example, formed from a single piece with electrode 34 arranged on said module. Applying a voltage between membrane 22 and electrode 34 causes membrane 22 to be lowered towards electrode 34, as described above. If module 14 is a spintronic device, such a lowering of membrane 22 allows the operating range of said device to be modified.

[0066] For example, the invention makes it possible to modify the operating frequency of a spintronic detector or emitter, as described in documents WO2018 / 069255 A1, WO2018 / 069389 A1 or US8227099B2, or of a device having nanoneuron or synapse functions, as described in document WO 2020 / 021004.

[0067] The invention also makes it possible to modify the operating frequency of a spintronic filter or a spintronic phase shifter; or the frequency range of an energy harvesting device; or the magnetic field detection range of a spintronic sensor as described in document WO2022 / 069626.

[0068] Figure 6 shows a magneto-electric device 210 forming a variant embodiment of the device 10. The device 210 comprises a substrate 12 on which are arranged several magneto-electronic modules 14, 214, 314, networked by connections 216, 218. Each module 14, 214, 314 is associated with a membrane 22, 222, 322, suspended above said module, and with an electrode 34, 234, 334 disposed on said module.

[0069] One or each of membranes 22, 222, 322 can be integrated into a bridge architecture, as described below in support of figures 3 to 5 for membrane 122.

[0070] Each membrane 22, 222, 322 is capable of being elastically deformed under the effect of an electrical voltage applied between said membrane and the corresponding electrode 34, 234, 334, as described above.

[0071] By thus modifying the operating range of several magneto-electronic modules 14, 214, 314, it is possible to realize continuously tunable phase-controlled array antennas (true time-delay line arrays); or neural networks similar to those described in document WO 2020 / 021004; or detector / transmitter networks similar to those described in documents WO2018 / 069255 A1 and WO2018 / 069389 A1.

[0072] The magneto-electric device 110 in figures 3 to 5 will now be described in more detail.

[0073] In the embodiment shown in Figures 3 to 5, the device 110 is a magnonic device, that is, one capable of harnessing spin waves. In particular, the substrate 112 is magnetic, more specifically suited to the propagation of spin waves, especially in the longitudinal X direction. The substrate 112 can be ferromagnetic, terrimagnetic, or antiferromagnetic. In a preferred embodiment, the substrate 112 is a garnet substrate, particularly of the YIG (yttrium iron garnet) type.

[0074] Preferably, the substrate 112 of the device 110 is a thin film, with a thickness more preferably between 10 nm and 50 pm. As can be seen in Figures 4 and 5, said thin film is, for example, deposited on a flat support 155.

[0075] In the embodiment of Figures 3 to 5, the magneto-electronic module 114 is integrated into the substrate 112. More specifically, the module 114 is formed by a central zone 160 of said substrate, defined by the electrode 134 in contact with said central zone.

[0076] The electronic connections to module 114 are formed by a first 116 and a second 118 spin wave transducers, arranged on the main surface 126 of the substrate 114, on either side of the central area 160 along the longitudinal direction X.

[0077] Transducers 116 and 118, for example, have geometries such as GSG, U-shape, microstripe, stripline, and interdigitated contact. Transducers 116 and 118 are, for example, made of gold.

[0078] In the embodiment shown in Figures 3 to 5, the uprights 130 are formed as a single piece with the membrane 122 and have a thickness comparable to that of said membrane in a (Y, Z) plane. In other words, the membrane 122 and the uprights 130 form a bridge-like structure.

[0079] Preferably, the support structure 120 of the device 110 further comprises two feet 162 substantially flat and in contact with the main face 126 of the substrate 112. Each foot 162 is formed of a piece with an upright 130 and ensures the anchoring of said upright on the substrate 112.

[0080] The first 116 and second 118 spin wave transducers are separated by a length L (figure 3) along the longitudinal direction X; the dimension 150 of the membrane 122, along said longitudinal direction, is for example between 0.05*L and 1.5*L.

[0081] According to a particular embodiment, the dimension 150 of the membrane 122 is greater than or equal to 0.90*L, preferably greater than or equal to 0.95*L. In other words, according to such an embodiment, the membrane 122 substantially covers the medium of propagation of the spin waves.

[0082] The different positions of the membrane 122 of the device 110, particularly in the first, second, and third configurations described above, lead to the application of different magnetic fields to the magnetic substrate 112. The amplitude of the dipole field, and therefore the propagation frequency of the spin waves, is thus influenced. According to a first example detailed below, by operating at a fixed frequency and varying the position of the membrane 122, the dipole field radiated from the latter modifies the dispersion of the spin waves, in particular the wave vector, thus implying a change in the group velocity, and by extension, in the time delay of the spin waves. The device 110 can therefore form a phase shifter or tunable delay line.

[0083] According to a second detailed example below, by fixing the operating frequency and the wave vector (low instantaneous bandwidth), the device 110 can form a tunable RF filter.

[0084] A manufacturing process for device 110 will now be described.

[0085] First, the conductive electrode 134 is deposited on the substrate 112, thus defining the central region 160 and therefore the magneto-electronic module 114. The electrode 134 is, for example, formed of a platinum layer. Optionally, the dielectric layer 140 is then deposited on said electrode.

[0086] Next, the first 116 and second 118 transducers are deposited on the substrate 112 on either side of the electrode 134 along the X direction.

[0087] Next, a first mask 170 is deposited on the substrate 112 and on the electrode 134. The first mask 170 is for example formed of a first resin.

[0088] Next, a magnetic material 172, precursor to the feet 162, the uprights 130, and the membrane 122, is deposited on the first mask 170 and on the substrate 112, on either side of said first mask. The magnetic material 172 is, for example, a hard magnetic material, particularly of the SmCo type, or a soft magnetic material but with strong saturation magnetization and a coercive field, particularly of the Co or NiFe type.

[0089] Next, a second mask 174 is placed on the magnetic material 172, so as to delimit the feet 162, the uprights 130 and the membrane 122.

[0090] An intermediate device 180, shown in figure 7, is thus obtained.

[0091] Next, portions 182 of the magnetic material 172, away from the second mask 174, are removed from the substrate 112. Preferably, said portions 182 are removed by dry ion etching or Ion Beam Etching.

[0092] The second mask 174 is then disposed of, as well as the first mask 170. Preferably, said masks are disposed of by etching with an oxygen plasma.

[0093] The membrane 122, suspended above the electrode 134, is thus obtained, as are the uprights 130 and the feet 162 formed in one piece with said membrane 122. Such a manufacturing process for the device 110 is compatible with the use of a magnonic substrate 112. In particular, the process does not involve the use of strong acids.

[0094] Examples of the implementation of the 110 magnonic device will now be described in more detail.

[0095] EXAMPLE 1

[0096] Example 1 corresponds to the magnonic device 110 described above, in the case where the dimension 150 of the membrane 122, along the longitudinal direction X, is substantially equal to the length L between the first 116 and second 118 spin-wave transducers. In other words, according to such an embodiment, the membrane 122 substantially covers the spin-wave propagation medium.

[0097] The magnonic 112 substrate is a YIG garnet with a thickness of 500 nm along Z.

[0098] The suspended membrane 122 is made of Co, with a length of 100 pm along Y; a width of 150 (figure 3) of 10 pm along X; and a thickness of 1 pm along Z.

[0099] The saturation magnetization Ms of membrane 122 is equal to 1.1 x 10 6 A / m; An exchange constant A ex of said membrane is equal to 2.5 x 10' 11 J / m.

[0100] Using a fixed permanent magnet, placed near device 110, a field of 150 mT is applied along the longitudinal direction X. Thus, a dipole field radiated by the membrane 122 is large enough to influence the internal field of the magnonic substrate 112.

[0101] This configuration, in which the applied magnetic field is parallel to the direction of spin wave propagation, corresponds to a Backward Volume Spin Wave (BVMSW) propagation mode. The dipole field radiated by this membrane can be estimated using MuMax3 micromagnetic simulations.

[0102] In the absence of voltage between membrane 122 and electrode 134, said membrane is at its base distance d0, for example 5 pm, above said electrode. The field then felt by the magnonic substrate 112 is 114.7 mT.

[0103] Next, by applying a voltage between the membrane 122 and the electrode 134, the membrane is lowered towards the electrode. This deformation occurs linearly and continuously as a function of the applied voltage, up to a threshold voltage Ts at which the membrane 122 comes into contact with the dielectric layer 140 covering the electrode 134. The membrane is then said to switch. For example, if a voltage is applied sufficient to lower the membrane 122 by 1 pm relative to d0, the distance d2 relative to the electrode is then on the order of 4 pm. The magnetic field then felt by the magnonic substrate 112 is 106.3 mT.

[0104] Thus, between these two configurations, an applied field difference of 8 mT is obtained. This difference in the dipole field D radiated by the membrane 122 and applied to the magnonic substrate 112, as schematically represented in Figure 8, modifies the dispersion of the spin waves.

[0105] Thus, for a certain frequency band, the wave vectors of the spin waves will be modified accordingly, resulting in different group velocities of the spin waves and therefore a variation in the time delay or phase shift of the detected spin waves. Over a distance L of 10 pm between transducers 116 and 118, the variation in the spin wave delay between the two distances d0 and d2 can range from 1.25 to 0.8 ns in the instantaneous operating frequency band.

[0106] Device 110 can thus form a phase shifter or tunable delay line, which can be used as an elementary unit of a phase-controlled array antenna.

[0107] It is also possible not to apply an external magnetic field, particularly in the case of a bridge with a magnetic material possessing a strong magneto-crystalline anisotropy (uniaxial or cubic) such as SmCo for example.

[0108] It then becomes possible to obtain uniform magnetization along the longitudinal X direction, generating a dipole field sufficient for proper propagation of spin waves in the YIG, without resorting to an external magnetic field. This makes it possible to create an integrable, reconfigurable, and energy-efficient magnonic device.

[0109] EXAMPLE 2

[0110] Like example 1, example 2 corresponds to the magnonic device 110 described above, in the case where the membrane 122 substantially covers the medium of propagation of the spin waves.

[0111] A magnetic field is applied almost uniformly to the magnonic substrate 112, which allows the propagation frequencies of the spin waves to be fixed. By fixing the wave vector of the spin waves that can be excited, notably through the dimensions and design of the transducers 116, 118, a narrow frequency bandwidth is obtained, thus constituting an RF filter. By continuously bringing the membrane 122 and the electrode 134 closer together, the dipole field varies, and therefore the frequency filter of the spin waves also varies.

[0112] The 110 device can thus form a tunable RF filter, particularly for 5G and beyond communications.

[0113] EXAMPLE 3

[0114] Example 3 corresponds to the magnonic device 110 described above, but in the case where dimension 150 of the membrane 122, along the longitudinal direction X, is less than dimension 152 of the electrode 134, as in device 10 of figure 1.

[0115] The Y-length of membrane 122 is on the order of 100 pm.

[0116] By continuously lowering the membrane 122 by applying a voltage, as described previously, a local perturbation of the dipole field of the magnonic substrate 112 is achieved, locally altering the frequency and therefore the wavelength of the spin waves. The spin wave signal detected at the transducers 116, 118 can thus be phase-shifted at specific frequencies. A fixed permanent magnet or other membranes can be added nearby to fix the operating frequencies.

[0117] Thus, as described above, devices 10, 110 are of micrometric dimensions, therefore compact, and are also reconfigurable and energy efficient.

Claims

DEMANDS 1. Magneto-electric device (10, 110, 210), comprising: - a substrate (12, 112) comprising a principal surface (26, 126), substantially flat; - a magneto-electronic module (14, 114), attached to the main surface of the substrate; said module being capable of analyzing and / or generating and / or propagating and / or conditioning an electronic signal; - a first (16, 116) and a second (18, 118) electronic connections to the magneto-electronic module (14, 114); - a magnetic element (22, 122), disposed at a non-zero distance from the magneto-electronic module; and - an actuation member (24, 124), capable of modifying the non-zero distance between said magnetic element and the magneto-electronic module; the magneto-electric device being characterized in that: - it further comprises a first and a second upright (30, 130), each of said uprights extending from the main surface (26, 126) of the substrate to a free end (32, 132), distant from said main surface; the first and second uprights being arranged on either side of the magneto-electronic module in a first direction (Y); - the actuation member comprises a conductive electrode (34, 134), disposed on the magneto-electronic module (14, 114) and between the first and second uprights (30, 130) along the first direction (Y); and - the magnetic element includes a suspended membrane (22, 122), extending between the free ends (32, 132) of the first and second uprights, opposite the electrode (34, 134); said membrane (22, 122) being able to be elastically deformed under the effect of an electrical voltage applied between said membrane and the electrode, so as to bring said membrane closer to and / or further away from said electrode.

2. Magneto-electric device according to claim 1, configured such that: - For a zero electrical voltage between the membrane (22, 122) and the electrode (34, 134), the distance between said membrane and said electrode is equal to a first value do; - For an electrical voltage greater than or equal to a threshold value T s non-zero, between the membrane (22, 122) and the electrode (34, 134), the distance between said membrane and said electrode is equal to a second value di, less than the first value do; and - for an electrical voltage T, non-zero and less than the threshold value T s, between the membrane (22, 122) and the electrode (34, 134), the distance between said membrane and said electrode is equal to a third value d2 such that di < d2 < do.

3. Magneto-electric device according to claim 2, configured such that, when the electrical voltage T between the membrane (22, 122) and the electrode (34, 134) is less than the threshold value T s , a difference (do - d2) is approximately proportional to T.

4. Magneto-electric device according to any one of the preceding claims, in which the membrane (22, 122) and the first and second uprights (30, 130) are formed of one piece.

5. Magneto-electric device according to any one of the preceding claims, wherein the magneto-electronic module (14, 114) comprises one or more layers of materials, magnetic or non-magnetic, suitable for the propagation of spin-polarized currents, spin waves or spin waves.

6. Magneto-electric device (10) according to any one of the preceding claims, wherein a dimension (50) of the membrane (22) along a second direction (X), perpendicular to the first direction (Y), is less than or equal to a dimension (52) of the electrode (34) conducting along said second direction.

7. Magneto-electric device (110) according to any one of claims 1 to 5, wherein a dimension (150) of the membrane (122) along a second direction (X), perpendicular to the first direction (Y), is greater than a dimension (152) of the electrode (134) conducting along said second direction.

8. Magneto-electric device (210) according to any one of the preceding claims, comprising a plurality of magneto-electronic modules (14, 214) arranged on the substrate (12) and connected to each other, each module being associated with a conductive electrode (34, 234) disposed on said module, and with a membrane (22, 222) suspended above said module, each membrane (22, 222) being capable of being elastically deformed under the effect of an electrical voltage applied between said membrane and the corresponding electrode.16 9. Magneto-electric device (110) according to any one of the preceding claims, wherein: the substrate (112) is suitable for the propagation of spin waves, the magneto-electronic module being formed by a central zone (160) of said substrate; and the first (116) and second (118) electronic connections to the magneto-electronic module are formed respectively by a first and a second spin-wave transducer, arranged on the main surface of the substrate, on either side of the central zone (160) along a second direction (X), perpendicular to the first direction (Y).

10. Magneto-electric device according to claim 9 taken in combination with claim 7, wherein: the first (116) and second (118) electronic connections are separated by a length L along the second direction (X); and the dimension (150) of the membrane (122) along said second direction is greater than or equal to 0.90*L, preferably greater than or equal to 0.95*L.

11. A method for manufacturing a magneto-electric device (110) according to any one of the preceding claims, comprising the following steps: - deposition of the conductive electrode (134) onto the magneto-electronic module (114, 160); and preferably, deposition of the electronic connections (116, 118) onto the substrate (112); then - deposition of a first mask (170) on the substrate (112) and on the electrode (134); then - deposition of a magnetic material (172) on the substrate (112) and on the first mask (170); then - deposition of a second mask (174) on said magnetic material; then - elimination of portions (182) of the magnetic material (172), distant from the first (170) and second (174) masks; then - elimination of the second (174) and first (170) masks, the magnetic material thus released forming the membrane (122) and the first and second uprights (130).

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